CINXE.COM

SRM Definitions | NIST

<!DOCTYPE html> <html lang="en" dir="ltr" prefix="content: http://purl.org/rss/1.0/modules/content/ dc: http://purl.org/dc/terms/ foaf: http://xmlns.com/foaf/0.1/ og: http://ogp.me/ns# rdfs: http://www.w3.org/2000/01/rdf-schema# schema: http://schema.org/ sioc: http://rdfs.org/sioc/ns# sioct: http://rdfs.org/sioc/types# skos: http://www.w3.org/2004/02/skos/core# xsd: http://www.w3.org/2001/XMLSchema# "> <head><script type="text/javascript" src="https://web-static.archive.org/_static/js/bundle-playback.js?v=7YQSqjSh" charset="utf-8"></script> <script type="text/javascript" src="https://web-static.archive.org/_static/js/wombat.js?v=txqj7nKC" charset="utf-8"></script> <script>window.RufflePlayer=window.RufflePlayer||{};window.RufflePlayer.config={"autoplay":"on","unmuteOverlay":"hidden"};</script> <script type="text/javascript" src="https://web-static.archive.org/_static/js/ruffle/ruffle.js"></script> <script type="text/javascript"> __wm.init("https://web.archive.org/web"); __wm.wombat("https://www.nist.gov/srm/srm-definitions","20231128043039","https://web.archive.org/","web","https://web-static.archive.org/_static/", "1701145839"); </script> <link rel="stylesheet" type="text/css" href="https://web-static.archive.org/_static/css/banner-styles.css?v=p7PEIJWi" /> <link rel="stylesheet" type="text/css" href="https://web-static.archive.org/_static/css/iconochive.css?v=3PDvdIFv" /> <!-- End Wayback Rewrite JS Include --> <meta charset="utf-8"/><script type="text/javascript">(window.NREUM||(NREUM={})).init={ajax:{deny_list:["gov-bam.nr-data.net"]}};(window.NREUM||(NREUM={})).loader_config={licenseKey:"37b7ccb661",applicationID:"1089704227"};;/*! For license information please see nr-loader-rum-1.248.0.min.js.LICENSE.txt */ (()=>{var e,t,n={234:(e,t,n)=>{"use strict";n.d(t,{P_:()=>h,Mt:()=>m,C5:()=>s,DL:()=>w,OP:()=>j,lF:()=>R,Yu:()=>_,Dg:()=>v,CX:()=>c,GE:()=>A,sU:()=>T});var r=n(8632),i=n(9567);const a={beacon:r.ce.beacon,errorBeacon:r.ce.errorBeacon,licenseKey:void 0,applicationID:void 0,sa:void 0,queueTime:void 0,applicationTime:void 0,ttGuid:void 0,user:void 0,account:void 0,product:void 0,extra:void 0,jsAttributes:{},userAttributes:void 0,atts:void 0,transactionName:void 0,tNamePlain:void 0},o={};function s(e){if(!e)throw new Error("All info objects require an agent identifier!");if(!o[e])throw new Error("Info for ".concat(e," was never set"));return o[e]}function c(e,t){if(!e)throw new Error("All info objects require an agent identifier!");o[e]=(0,i.D)(t,a);const n=(0,r.ek)(e);n&&(n.info=o[e])}const u=e=>{if(!e||"string"!=typeof e)return!1;try{document.createDocumentFragment().querySelector(e)}catch{return!1}return!0};var d=n(7056),l=n(50);const f=()=>{const e={mask_selector:"*",block_selector:"[data-nr-block]",mask_input_options:{color:!1,date:!1,"datetime-local":!1,email:!1,month:!1,number:!1,range:!1,search:!1,tel:!1,text:!1,time:!1,url:!1,week:!1,textarea:!1,select:!1,password:!0}};return{feature_flags:[],proxy:{assets:void 0,beacon:void 0},privacy:{cookies_enabled:!0},ajax:{deny_list:void 0,block_internal:!0,enabled:!0,harvestTimeSeconds:10,autoStart:!0},distributed_tracing:{enabled:void 0,exclude_newrelic_header:void 0,cors_use_newrelic_header:void 0,cors_use_tracecontext_headers:void 0,allowed_origins:void 0},session:{domain:void 0,expiresMs:d.oD,inactiveMs:d.Hb},ssl:void 0,obfuscate:void 0,jserrors:{enabled:!0,harvestTimeSeconds:10,autoStart:!0},metrics:{enabled:!0,autoStart:!0},page_action:{enabled:!0,harvestTimeSeconds:30,autoStart:!0},page_view_event:{enabled:!0,autoStart:!0},page_view_timing:{enabled:!0,harvestTimeSeconds:30,long_task:!1,autoStart:!0},session_trace:{enabled:!0,harvestTimeSeconds:10,autoStart:!0},harvest:{tooManyRequestsDelay:60},session_replay:{autoStart:!0,enabled:!1,harvestTimeSeconds:60,sampling_rate:50,error_sampling_rate:50,collect_fonts:!1,inline_images:!1,inline_stylesheet:!0,mask_all_inputs:!0,get mask_text_selector(){return e.mask_selector},set mask_text_selector(t){u(t)?e.mask_selector=t+",[data-nr-mask]":null===t?e.mask_selector=t:(0,l.Z)("An invalid session_replay.mask_selector was provided and will not be used",t)},get block_class(){return"nr-block"},get ignore_class(){return"nr-ignore"},get mask_text_class(){return"nr-mask"},get block_selector(){return e.block_selector},set block_selector(t){u(t)?e.block_selector+=",".concat(t):""!==t&&(0,l.Z)("An invalid session_replay.block_selector was provided and will not be used",t)},get mask_input_options(){return e.mask_input_options},set mask_input_options(t){t&&"object"==typeof t?e.mask_input_options={...t,password:!0}:(0,l.Z)("An invalid session_replay.mask_input_option was provided and will not be used",t)}},spa:{enabled:!0,harvestTimeSeconds:10,autoStart:!0}}},g={},p="All configuration objects require an agent identifier!";function h(e){if(!e)throw new Error(p);if(!g[e])throw new Error("Configuration for ".concat(e," was never set"));return g[e]}function v(e,t){if(!e)throw new Error(p);g[e]=(0,i.D)(t,f());const n=(0,r.ek)(e);n&&(n.init=g[e])}function m(e,t){if(!e)throw new Error(p);var n=h(e);if(n){for(var r=t.split("."),i=0;i<r.length-1;i++)if("object"!=typeof(n=n[r[i]]))return;n=n[r[r.length-1]]}return n}const b={accountID:void 0,trustKey:void 0,agentID:void 0,licenseKey:void 0,applicationID:void 0,xpid:void 0},y={};function w(e){if(!e)throw new Error("All loader-config objects require an agent identifier!");if(!y[e])throw new Error("LoaderConfig for ".concat(e," was never set"));return y[e]}function A(e,t){if(!e)throw new Error("All loader-config objects require an agent identifier!");y[e]=(0,i.D)(t,b);const n=(0,r.ek)(e);n&&(n.loader_config=y[e])}const _=(0,r.mF)().o;var x=n(385),D=n(6818);const k={buildEnv:D.Re,customTransaction:void 0,disabled:!1,distMethod:D.gF,isolatedBacklog:!1,loaderType:void 0,maxBytes:3e4,offset:Math.floor(x._A?.performance?.timeOrigin||x._A?.performance?.timing?.navigationStart||Date.now()),onerror:void 0,origin:""+x._A.location,ptid:void 0,releaseIds:{},session:void 0,xhrWrappable:"function"==typeof x._A.XMLHttpRequest?.prototype?.addEventListener,version:D.q4,denyList:void 0},E={};function j(e){if(!e)throw new Error("All runtime objects require an agent identifier!");if(!E[e])throw new Error("Runtime for ".concat(e," was never set"));return E[e]}function T(e,t){if(!e)throw new Error("All runtime objects require an agent identifier!");E[e]=(0,i.D)(t,k);const n=(0,r.ek)(e);n&&(n.runtime=E[e])}function R(e){return function(e){try{const t=s(e);return!!t.licenseKey&&!!t.errorBeacon&&!!t.applicationID}catch(e){return!1}}(e)}},9567:(e,t,n)=>{"use strict";n.d(t,{D:()=>i});var r=n(50);function i(e,t){try{if(!e||"object"!=typeof e)return(0,r.Z)("Setting a Configurable requires an object as input");if(!t||"object"!=typeof t)return(0,r.Z)("Setting a Configurable requires a model to set its initial properties");const n=Object.create(Object.getPrototypeOf(t),Object.getOwnPropertyDescriptors(t)),a=0===Object.keys(n).length?e:n;for(let o in a)if(void 0!==e[o])try{Array.isArray(e[o])&&Array.isArray(t[o])?n[o]=Array.from(new Set([...e[o],...t[o]])):"object"==typeof e[o]&&"object"==typeof t[o]?n[o]=i(e[o],t[o]):n[o]=e[o]}catch(e){(0,r.Z)("An error occurred while setting a property of a Configurable",e)}return n}catch(e){(0,r.Z)("An error occured while setting a Configurable",e)}}},6818:(e,t,n)=>{"use strict";n.d(t,{Re:()=>i,gF:()=>a,q4:()=>r});const r="1.248.0",i="PROD",a="CDN"},385:(e,t,n)=>{"use strict";n.d(t,{Nk:()=>d,Tt:()=>s,_A:()=>a,cv:()=>l,iS:()=>o,il:()=>r,ux:()=>c,v6:()=>i,w1:()=>u});const r="undefined"!=typeof window&&!!window.document,i="undefined"!=typeof WorkerGlobalScope&&("undefined"!=typeof self&&self instanceof WorkerGlobalScope&&self.navigator instanceof WorkerNavigator||"undefined"!=typeof globalThis&&globalThis instanceof WorkerGlobalScope&&globalThis.navigator instanceof WorkerNavigator),a=r?window:"undefined"!=typeof WorkerGlobalScope&&("undefined"!=typeof self&&self instanceof WorkerGlobalScope&&self||"undefined"!=typeof globalThis&&globalThis instanceof WorkerGlobalScope&&globalThis),o=(a?.document?.readyState,Boolean("hidden"===a?.document?.visibilityState)),s=(a?.location,/iPad|iPhone|iPod/.test(a.navigator?.userAgent)),c=s&&"undefined"==typeof SharedWorker,u=((()=>{const e=a.navigator?.userAgent?.match(/Firefox[/\s](\d+\.\d+)/);Array.isArray(e)&&e.length>=2&&e[1]})(),Boolean(r&&window.document.documentMode)),d=!!a.navigator?.sendBeacon,l=Math.floor(a?.performance?.timeOrigin||a?.performance?.timing?.navigationStart||Date.now())},1117:(e,t,n)=>{"use strict";n.d(t,{w:()=>a});var r=n(50);const i={agentIdentifier:"",ee:void 0};class a{constructor(e){try{if("object"!=typeof e)return(0,r.Z)("shared context requires an object as input");this.sharedContext={},Object.assign(this.sharedContext,i),Object.entries(e).forEach((e=>{let[t,n]=e;Object.keys(i).includes(t)&&(this.sharedContext[t]=n)}))}catch(e){(0,r.Z)("An error occured while setting SharedContext",e)}}}},8e3:(e,t,n)=>{"use strict";n.d(t,{L:()=>d,R:()=>c});var r=n(8325),i=n(1284),a=n(4322),o=n(3325);const s={};function c(e,t){const n={staged:!1,priority:o.p[t]||0};u(e),s[e].get(t)||s[e].set(t,n)}function u(e){e&&(s[e]||(s[e]=new Map))}function d(){let e=arguments.length>0&&void 0!==arguments[0]?arguments[0]:"",t=arguments.length>1&&void 0!==arguments[1]?arguments[1]:"feature";if(u(e),!e||!s[e].get(t))return o(t);s[e].get(t).staged=!0;const n=[...s[e]];function o(t){const n=e?r.ee.get(e):r.ee,o=a.X.handlers;if(n.backlog&&o){var s=n.backlog[t],c=o[t];if(c){for(var u=0;s&&u<s.length;++u)l(s[u],c);(0,i.D)(c,(function(e,t){(0,i.D)(t,(function(t,n){n[0].on(e,n[1])}))}))}delete o[t],n.backlog[t]=null,n.emit("drain-"+t,[])}}n.every((e=>{let[t,n]=e;return n.staged}))&&(n.sort(((e,t)=>e[1].priority-t[1].priority)),n.forEach((t=>{let[n]=t;s[e].delete(n),o(n)})))}function l(e,t){var n=e[1];(0,i.D)(t[n],(function(t,n){var r=e[0];if(n[0]===r){var i=n[1],a=e[3],o=e[2];i.apply(a,o)}}))}},8325:(e,t,n)=>{"use strict";n.d(t,{A:()=>c,ee:()=>u});var r=n(8632),i=n(2210),a=n(234);class o{constructor(e){this.contextId=e}}var s=n(3117);const c="nr@context:".concat(s.a),u=function e(t,n){var r={},s={},d={},f=!1;try{f=16===n.length&&(0,a.OP)(n).isolatedBacklog}catch(e){}var g={on:h,addEventListener:h,removeEventListener:function(e,t){var n=r[e];if(!n)return;for(var i=0;i<n.length;i++)n[i]===t&&n.splice(i,1)},emit:function(e,n,r,i,a){!1!==a&&(a=!0);if(u.aborted&&!i)return;t&&a&&t.emit(e,n,r);for(var o=p(r),c=v(e),d=c.length,l=0;l<d;l++)c[l].apply(o,n);var f=b()[s[e]];f&&f.push([g,e,n,o]);return o},get:m,listeners:v,context:p,buffer:function(e,t){const n=b();if(t=t||"feature",g.aborted)return;Object.entries(e||{}).forEach((e=>{let[r,i]=e;s[i]=t,t in n||(n[t]=[])}))},abort:l,aborted:!1,isBuffering:function(e){return!!b()[s[e]]},debugId:n,backlog:f?{}:t&&"object"==typeof t.backlog?t.backlog:{}};return g;function p(e){return e&&e instanceof o?e:e?(0,i.X)(e,c,(()=>new o(c))):new o(c)}function h(e,t){r[e]=v(e).concat(t)}function v(e){return r[e]||[]}function m(t){return d[t]=d[t]||e(g,t)}function b(){return g.backlog}}(void 0,"globalEE"),d=(0,r.fP)();function l(){u.aborted=!0,u.backlog={}}d.ee||(d.ee=u)},5546:(e,t,n)=>{"use strict";n.d(t,{E:()=>r,p:()=>i});var r=n(8325).ee.get("handle");function i(e,t,n,i,a){a?(a.buffer([e],i),a.emit(e,t,n)):(r.buffer([e],i),r.emit(e,t,n))}},4322:(e,t,n)=>{"use strict";n.d(t,{X:()=>a});var r=n(5546);a.on=o;var i=a.handlers={};function a(e,t,n,a){o(a||r.E,i,e,t,n)}function o(e,t,n,i,a){a||(a="feature"),e||(e=r.E);var o=t[a]=t[a]||{};(o[n]=o[n]||[]).push([e,i])}},3239:(e,t,n)=>{"use strict";n.d(t,{bP:()=>s,iz:()=>c,m$:()=>o});var r=n(385);let i=!1,a=!1;try{const e={get passive(){return i=!0,!1},get signal(){return a=!0,!1}};r._A.addEventListener("test",null,e),r._A.removeEventListener("test",null,e)}catch(e){}function o(e,t){return i||a?{capture:!!e,passive:i,signal:t}:!!e}function s(e,t){let n=arguments.length>2&&void 0!==arguments[2]&&arguments[2],r=arguments.length>3?arguments[3]:void 0;window.addEventListener(e,t,o(n,r))}function c(e,t){let n=arguments.length>2&&void 0!==arguments[2]&&arguments[2],r=arguments.length>3?arguments[3]:void 0;document.addEventListener(e,t,o(n,r))}},3117:(e,t,n)=>{"use strict";n.d(t,{a:()=>r});const r=(0,n(4402).Rl)()},4402:(e,t,n)=>{"use strict";n.d(t,{Rl:()=>o,ky:()=>s});var r=n(385);const i="xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx";function a(e,t){return e?15&e[t]:16*Math.random()|0}function o(){const e=r._A?.crypto||r._A?.msCrypto;let t,n=0;return e&&e.getRandomValues&&(t=e.getRandomValues(new Uint8Array(31))),i.split("").map((e=>"x"===e?a(t,++n).toString(16):"y"===e?(3&a()|8).toString(16):e)).join("")}function s(e){const t=r._A?.crypto||r._A?.msCrypto;let n,i=0;t&&t.getRandomValues&&(n=t.getRandomValues(new Uint8Array(31)));const o=[];for(var s=0;s<e;s++)o.push(a(n,++i).toString(16));return o.join("")}},7056:(e,t,n)=>{"use strict";n.d(t,{Bq:()=>r,Hb:()=>a,oD:()=>i});const r="NRBA",i=144e5,a=18e5},7894:(e,t,n)=>{"use strict";function r(){return Math.round(performance.now())}n.d(t,{z:()=>r})},50:(e,t,n)=>{"use strict";function r(e,t){"function"==typeof console.warn&&(console.warn("New Relic: ".concat(e)),t&&console.warn(t))}n.d(t,{Z:()=>r})},2825:(e,t,n)=>{"use strict";n.d(t,{N:()=>d,T:()=>l});var r=n(8325),i=n(5546),a=n(3325),o=n(385);const s="newrelic";const c={stn:[a.D.sessionTrace],err:[a.D.jserrors,a.D.metrics],ins:[a.D.pageAction],spa:[a.D.spa],sr:[a.D.sessionReplay,a.D.sessionTrace]},u=new Set;function d(e,t){const n=r.ee.get(t);e&&"object"==typeof e&&(u.has(t)||(Object.entries(e).forEach((e=>{let[t,r]=e;c[t]?c[t].forEach((e=>{r?(0,i.p)("feat-"+t,[],void 0,e,n):(0,i.p)("block-"+t,[],void 0,e,n),(0,i.p)("rumresp-"+t,[Boolean(r)],void 0,e,n)})):r&&(0,i.p)("feat-"+t,[],void 0,void 0,n),l[t]=Boolean(r)})),Object.keys(c).forEach((e=>{void 0===l[e]&&(c[e]?.forEach((t=>(0,i.p)("rumresp-"+e,[!1],void 0,t,n))),l[e]=!1)})),u.add(t),function(){let e=arguments.length>0&&void 0!==arguments[0]?arguments[0]:{};try{o._A.dispatchEvent(new CustomEvent(s,{detail:e}))}catch(e){}}({loaded:!0})))}const l={}},2210:(e,t,n)=>{"use strict";n.d(t,{X:()=>i});var r=Object.prototype.hasOwnProperty;function i(e,t,n){if(r.call(e,t))return e[t];var i=n();if(Object.defineProperty&&Object.keys)try{return Object.defineProperty(e,t,{value:i,writable:!0,enumerable:!1}),i}catch(e){}return e[t]=i,i}},1284:(e,t,n)=>{"use strict";n.d(t,{D:()=>r});const r=(e,t)=>Object.entries(e||{}).map((e=>{let[n,r]=e;return t(n,r)}))},4351:(e,t,n)=>{"use strict";n.d(t,{P:()=>a});var r=n(8325);const i=()=>{const e=new WeakSet;return(t,n)=>{if("object"==typeof n&&null!==n){if(e.has(n))return;e.add(n)}return n}};function a(e){try{return JSON.stringify(e,i())}catch(e){try{r.ee.emit("internal-error",[e])}catch(e){}}}},3960:(e,t,n)=>{"use strict";n.d(t,{KB:()=>o,b2:()=>a});var r=n(3239);function i(){return"undefined"==typeof document||"complete"===document.readyState}function a(e,t){if(i())return e();(0,r.bP)("load",e,t)}function o(e){if(i())return e();(0,r.iz)("DOMContentLoaded",e)}},8632:(e,t,n)=>{"use strict";n.d(t,{EZ:()=>d,ce:()=>a,ek:()=>u,fP:()=>o,gG:()=>l,h5:()=>c,mF:()=>s});var r=n(7894),i=n(385);const a={beacon:"bam.nr-data.net",errorBeacon:"bam.nr-data.net"};function o(){return i._A.NREUM||(i._A.NREUM={}),void 0===i._A.newrelic&&(i._A.newrelic=i._A.NREUM),i._A.NREUM}function s(){let e=o();return e.o||(e.o={ST:i._A.setTimeout,SI:i._A.setImmediate,CT:i._A.clearTimeout,XHR:i._A.XMLHttpRequest,REQ:i._A.Request,EV:i._A.Event,PR:i._A.Promise,MO:i._A.MutationObserver,FETCH:i._A.fetch}),e}function c(e,t){let n=o();n.initializedAgents??={},t.initializedAt={ms:(0,r.z)(),date:new Date},n.initializedAgents[e]=t}function u(e){let t=o();return t.initializedAgents?.[e]}function d(e,t){o()[e]=t}function l(){return function(){let e=o();const t=e.info||{};e.info={beacon:a.beacon,errorBeacon:a.errorBeacon,...t}}(),function(){let e=o();const t=e.init||{};e.init={...t}}(),s(),function(){let e=o();const t=e.loader_config||{};e.loader_config={...t}}(),o()}},7956:(e,t,n)=>{"use strict";n.d(t,{N:()=>i});var r=n(3239);function i(e){let t=arguments.length>1&&void 0!==arguments[1]&&arguments[1],n=arguments.length>2?arguments[2]:void 0,i=arguments.length>3?arguments[3]:void 0;(0,r.iz)("visibilitychange",(function(){if(t)return void("hidden"===document.visibilityState&&e());e(document.visibilityState)}),n,i)}},3081:(e,t,n)=>{"use strict";n.d(t,{gF:()=>a,mY:()=>i,t9:()=>r,vz:()=>s,xS:()=>o});const r=n(3325).D.metrics,i="sm",a="cm",o="storeSupportabilityMetrics",s="storeEventMetrics"},7633:(e,t,n)=>{"use strict";n.d(t,{t:()=>r});const r=n(3325).D.pageViewEvent},9251:(e,t,n)=>{"use strict";n.d(t,{t:()=>r});const r=n(3325).D.pageViewTiming},5938:(e,t,n)=>{"use strict";n.d(t,{W:()=>i});var r=n(8325);class i{constructor(e,t,n){this.agentIdentifier=e,this.aggregator=t,this.ee=r.ee.get(e),this.featureName=n,this.blocked=!1}}},7530:(e,t,n)=>{"use strict";n.d(t,{j:()=>b});var r=n(3325),i=n(234),a=n(5546),o=n(8325),s=n(7894),c=n(8e3),u=n(3960),d=n(385),l=n(50),f=n(3081),g=n(8632);function p(){const e=(0,g.gG)();["setErrorHandler","finished","addToTrace","addRelease","addPageAction","setCurrentRouteName","setPageViewName","setCustomAttribute","interaction","noticeError","setUserId","setApplicationVersion","start","recordReplay","pauseReplay"].forEach((t=>{e[t]=function(){for(var n=arguments.length,r=new Array(n),i=0;i<n;i++)r[i]=arguments[i];return function(t){for(var n=arguments.length,r=new Array(n>1?n-1:0),i=1;i<n;i++)r[i-1]=arguments[i];let a=[];return Object.values(e.initializedAgents).forEach((e=>{e.exposed&&e.api[t]&&a.push(e.api[t](...r))})),a.length>1?a:a[0]}(t,...r)}}))}var h=n(2825);const v=e=>{const t=e.startsWith("http");e+="/",n.p=t?e:"https://"+e};let m=!1;function b(e){let t=arguments.length>1&&void 0!==arguments[1]?arguments[1]:{},b=arguments.length>2?arguments[2]:void 0,y=arguments.length>3?arguments[3]:void 0,{init:w,info:A,loader_config:_,runtime:x={loaderType:b},exposed:D=!0}=t;const k=(0,g.gG)();A||(w=k.init,A=k.info,_=k.loader_config),(0,i.Dg)(e.agentIdentifier,w||{}),(0,i.GE)(e.agentIdentifier,_||{}),A.jsAttributes??={},d.v6&&(A.jsAttributes.isWorker=!0),(0,i.CX)(e.agentIdentifier,A);const E=(0,i.P_)(e.agentIdentifier),j=[A.beacon,A.errorBeacon];m||(E.proxy.assets&&(v(E.proxy.assets),j.push(E.proxy.assets)),E.proxy.beacon&&j.push(E.proxy.beacon),p(),(0,g.EZ)("activatedFeatures",h.T)),x.denyList=[...E.ajax.deny_list||[],...E.ajax.block_internal?j:[]],(0,i.sU)(e.agentIdentifier,x),void 0===e.api&&(e.api=function(e,t){t||(0,c.R)(e,"api");const g={};var p=o.ee.get(e),h=p.get("tracer"),v="api-",m=v+"ixn-";function b(t,n,r,a){const o=(0,i.C5)(e);return null===n?delete o.jsAttributes[t]:(0,i.CX)(e,{...o,jsAttributes:{...o.jsAttributes,[t]:n}}),A(v,r,!0,a||null===n?"session":void 0)(t,n)}function y(){}["setErrorHandler","finished","addToTrace","addRelease"].forEach((e=>{g[e]=A(v,e,!0,"api")})),g.addPageAction=A(v,"addPageAction",!0,r.D.pageAction),g.setCurrentRouteName=A(v,"routeName",!0,r.D.spa),g.setPageViewName=function(t,n){if("string"==typeof t)return"/"!==t.charAt(0)&&(t="/"+t),(0,i.OP)(e).customTransaction=(n||"https://web.archive.org/web/20231128043039/http://custom.transaction")+t,A(v,"setPageViewName",!0)()},g.setCustomAttribute=function(e,t){let n=arguments.length>2&&void 0!==arguments[2]&&arguments[2];if("string"==typeof e){if(["string","number","boolean"].includes(typeof t)||null===t)return b(e,t,"setCustomAttribute",n);(0,l.Z)("Failed to execute setCustomAttribute.\nNon-null value must be a string, number or boolean type, but a type of <".concat(typeof t,"> was provided."))}else(0,l.Z)("Failed to execute setCustomAttribute.\nName must be a string type, but a type of <".concat(typeof e,"> was provided."))},g.setUserId=function(e){if("string"==typeof e||null===e)return b("enduser.id",e,"setUserId",!0);(0,l.Z)("Failed to execute setUserId.\nNon-null value must be a string type, but a type of <".concat(typeof e,"> was provided."))},g.setApplicationVersion=function(e){if("string"==typeof e||null===e)return b("application.version",e,"setApplicationVersion",!1);(0,l.Z)("Failed to execute setApplicationVersion. Expected <String | null>, but got <".concat(typeof e,">."))},g.start=e=>{try{const t=e?"defined":"undefined";(0,a.p)(f.xS,["API/start/".concat(t,"/called")],void 0,r.D.metrics,p);const n=Object.values(r.D);if(void 0===e)e=n;else{if((e=Array.isArray(e)&&e.length?e:[e]).some((e=>!n.includes(e))))return(0,l.Z)("Invalid feature name supplied. Acceptable feature names are: ".concat(n));e.includes(r.D.pageViewEvent)||e.push(r.D.pageViewEvent)}e.forEach((e=>{p.emit("".concat(e,"-opt-in"))}))}catch(e){(0,l.Z)("An unexpected issue occurred",e)}},g.recordReplay=function(){(0,a.p)(f.xS,["API/recordReplay/called"],void 0,r.D.metrics,p),(0,a.p)("recordReplay",[],void 0,r.D.sessionReplay,p)},g.pauseReplay=function(){(0,a.p)(f.xS,["API/pauseReplay/called"],void 0,r.D.metrics,p),(0,a.p)("pauseReplay",[],void 0,r.D.sessionReplay,p)},g.interaction=function(){return(new y).get()};var w=y.prototype={createTracer:function(e,t){var n={},i=this,o="function"==typeof t;return(0,a.p)(f.xS,["API/createTracer/called"],void 0,r.D.metrics,p),(0,a.p)(m+"tracer",[(0,s.z)(),e,n],i,r.D.spa,p),function(){if(h.emit((o?"":"no-")+"fn-start",[(0,s.z)(),i,o],n),o)try{return t.apply(this,arguments)}catch(e){throw h.emit("fn-err",[arguments,this,e],n),e}finally{h.emit("fn-end",[(0,s.z)()],n)}}}};function A(e,t,n,i){return function(){return(0,a.p)(f.xS,["API/"+t+"/called"],void 0,r.D.metrics,p),i&&(0,a.p)(e+t,[(0,s.z)(),...arguments],n?null:this,i,p),n?void 0:this}}function _(){n.e(75).then(n.bind(n,7438)).then((t=>{let{setAPI:n}=t;n(e),(0,c.L)(e,"api")})).catch((()=>(0,l.Z)("Downloading runtime APIs failed...")))}return["actionText","setName","setAttribute","save","ignore","onEnd","getContext","end","get"].forEach((e=>{w[e]=A(m,e,void 0,r.D.spa)})),g.noticeError=function(e,t){"string"==typeof e&&(e=new Error(e)),(0,a.p)(f.xS,["API/noticeError/called"],void 0,r.D.metrics,p),(0,a.p)("err",[e,(0,s.z)(),!1,t],void 0,r.D.jserrors,p)},d.il?(0,u.b2)((()=>_()),!0):_(),g}(e.agentIdentifier,y)),void 0===e.exposed&&(e.exposed=D),m=!0}},1926:(e,t,n)=>{n.nc=(()=>{try{return document?.currentScript?.nonce}catch(e){}return""})()},3325:(e,t,n)=>{"use strict";n.d(t,{D:()=>r,p:()=>i});const r={ajax:"ajax",jserrors:"jserrors",metrics:"metrics",pageAction:"page_action",pageViewEvent:"page_view_event",pageViewTiming:"page_view_timing",sessionReplay:"session_replay",sessionTrace:"session_trace",spa:"spa"},i={[r.pageViewEvent]:1,[r.pageViewTiming]:2,[r.metrics]:3,[r.jserrors]:4,[r.ajax]:5,[r.sessionTrace]:6,[r.pageAction]:7,[r.spa]:8,[r.sessionReplay]:9}}},r={};function i(e){var t=r[e];if(void 0!==t)return t.exports;var a=r[e]={exports:{}};return n[e](a,a.exports,i),a.exports}i.m=n,i.d=(e,t)=>{for(var n in t)i.o(t,n)&&!i.o(e,n)&&Object.defineProperty(e,n,{enumerable:!0,get:t[n]})},i.f={},i.e=e=>Promise.all(Object.keys(i.f).reduce(((t,n)=>(i.f[n](e,t),t)),[])),i.u=e=>"nr-rum-1.248.0.min.js",i.o=(e,t)=>Object.prototype.hasOwnProperty.call(e,t),e={},t="NRBA-1.248.0.PROD:",i.l=(n,r,a,o)=>{if(e[n])e[n].push(r);else{var s,c;if(void 0!==a)for(var u=document.getElementsByTagName("script"),d=0;d<u.length;d++){var l=u[d];if(l.getAttribute("src")==n||l.getAttribute("data-webpack")==t+a){s=l;break}}s||(c=!0,(s=document.createElement("script")).charset="utf-8",s.timeout=120,i.nc&&s.setAttribute("nonce",i.nc),s.setAttribute("data-webpack",t+a),s.src=n,0!==s.src.indexOf(window.location.origin+"/")&&(s.crossOrigin="anonymous"),s.integrity=i.sriHashes[o],s.crossOrigin="anonymous"),e[n]=[r];var f=(t,r)=>{s.onerror=s.onload=null,clearTimeout(g);var i=e[n];if(delete e[n],s.parentNode&&s.parentNode.removeChild(s),i&&i.forEach((e=>e(r))),t)return t(r)},g=setTimeout(f.bind(null,void 0,{type:"timeout",target:s}),12e4);s.onerror=f.bind(null,s.onerror),s.onload=f.bind(null,s.onload),c&&document.head.appendChild(s)}},i.r=e=>{"undefined"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(e,Symbol.toStringTag,{value:"Module"}),Object.defineProperty(e,"__esModule",{value:!0})},i.p="https://web.archive.org/web/20231128043039/https://js-agent.newrelic.com/",i.sriHashes={75:"sha512-5mWtMwj7hrXT5aUkfvBtjH6FJXsR+zdeMBfc721nzrOx36xa23yTrCB1VVOAQa+zIioAbWPW4m7UsPp7hW1WPw=="},(()=>{var e={50:0,832:0};i.f.j=(t,n)=>{var r=i.o(e,t)?e[t]:void 0;if(0!==r)if(r)n.push(r[2]);else{var a=new Promise(((n,i)=>r=e[t]=[n,i]));n.push(r[2]=a);var o=i.p+i.u(t),s=new Error;i.l(o,(n=>{if(i.o(e,t)&&(0!==(r=e[t])&&(e[t]=void 0),r)){var a=n&&("load"===n.type?"missing":n.type),o=n&&n.target&&n.target.src;s.message="Loading chunk "+t+" failed.\n("+a+": "+o+")",s.name="ChunkLoadError",s.type=a,s.request=o,r[1](s)}}),"chunk-"+t,t)}};var t=(t,n)=>{var r,a,[o,s,c]=n,u=0;if(o.some((t=>0!==e[t]))){for(r in s)i.o(s,r)&&(i.m[r]=s[r]);if(c)c(i)}for(t&&t(n);u<o.length;u++)a=o[u],i.o(e,a)&&e[a]&&e[a][0](),e[a]=0},n=self["webpackChunk:NRBA-1.248.0.PROD"]=self["webpackChunk:NRBA-1.248.0.PROD"]||[];n.forEach(t.bind(null,0)),n.push=t.bind(null,n.push.bind(n))})(),(()=>{"use strict";i(1926);var e=i(50);class t{addPageAction(t,n){(0,e.Z)("Call to agent api addPageAction failed. The page action feature is not currently initialized.")}setPageViewName(t,n){(0,e.Z)("Call to agent api setPageViewName failed. The page view feature is not currently initialized.")}setCustomAttribute(t,n,r){(0,e.Z)("Call to agent api setCustomAttribute failed. The js errors feature is not currently initialized.")}noticeError(t,n){(0,e.Z)("Call to agent api noticeError failed. The js errors feature is not currently initialized.")}setUserId(t){(0,e.Z)("Call to agent api setUserId failed. The js errors feature is not currently initialized.")}setApplicationVersion(t){(0,e.Z)("Call to agent api setApplicationVersion failed. The agent is not currently initialized.")}setErrorHandler(t){(0,e.Z)("Call to agent api setErrorHandler failed. The js errors feature is not currently initialized.")}finished(t){(0,e.Z)("Call to agent api finished failed. The page action feature is not currently initialized.")}addRelease(t,n){(0,e.Z)("Call to agent api addRelease failed. The js errors feature is not currently initialized.")}start(t){(0,e.Z)("Call to agent api addRelease failed. The agent is not currently initialized.")}recordReplay(){(0,e.Z)("Call to agent api recordReplay failed. The agent is not currently initialized.")}pauseReplay(){(0,e.Z)("Call to agent api pauseReplay failed. The agent is not currently initialized.")}}var n=i(3325),r=i(234);const a=Object.values(n.D);function o(e){const t={};return a.forEach((n=>{t[n]=function(e,t){return!1!==(0,r.Mt)(t,"".concat(e,".enabled"))}(n,e)})),t}var s=i(7530);var c=i(8e3),u=i(5938),d=i(3960),l=i(385);class f extends u.W{constructor(e,t,n){let i=!(arguments.length>3&&void 0!==arguments[3])||arguments[3];super(e,t,n),this.auto=i,this.abortHandler=void 0,this.featAggregate=void 0,this.onAggregateImported=void 0,!1===(0,r.Mt)(this.agentIdentifier,"".concat(this.featureName,".autoStart"))&&(this.auto=!1),this.auto&&(0,c.R)(e,n)}importAggregator(){let t=arguments.length>0&&void 0!==arguments[0]?arguments[0]:{};if(this.featAggregate)return;if(!this.auto)return void this.ee.on("".concat(this.featureName,"-opt-in"),(()=>{(0,c.R)(this.agentIdentifier,this.featureName),this.auto=!0,this.importAggregator()}));const n=l.il&&!0===(0,r.Mt)(this.agentIdentifier,"privacy.cookies_enabled");let a;this.onAggregateImported=new Promise((e=>{a=e}));const o=async()=>{let r;try{if(n){const{setupAgentSession:e}=await i.e(75).then(i.bind(i,3228));r=e(this.agentIdentifier)}}catch(t){(0,e.Z)("A problem occurred when starting up session manager. This page will not start or extend any session.",t)}try{if(!this.shouldImportAgg(this.featureName,r))return(0,c.L)(this.agentIdentifier,this.featureName),void a(!1);const{lazyFeatureLoader:e}=await i.e(75).then(i.bind(i,8582)),{Aggregate:n}=await e(this.featureName,"aggregate");this.featAggregate=new n(this.agentIdentifier,this.aggregator,t),a(!0)}catch(t){(0,e.Z)("Downloading and initializing ".concat(this.featureName," failed..."),t),this.abortHandler?.(),(0,c.L)(this.agentIdentifier,this.featureName),a(!1)}};l.il?(0,d.b2)((()=>o()),!0):o()}shouldImportAgg(e,t){return e!==n.D.sessionReplay||!!r.Yu.MO&&(!1!==(0,r.Mt)(this.agentIdentifier,"session_trace.enabled")&&(!!t?.isNew||!!t?.state.sessionReplayMode))}}var g=i(7633);class p extends f{static featureName=g.t;constructor(e,t){let n=!(arguments.length>2&&void 0!==arguments[2])||arguments[2];super(e,t,g.t,n),this.importAggregator()}}var h=i(1117),v=i(1284);class m extends h.w{constructor(e){super(e),this.aggregatedData={}}store(e,t,n,r,i){var a=this.getBucket(e,t,n,i);return a.metrics=function(e,t){t||(t={count:0});return t.count+=1,(0,v.D)(e,(function(e,n){t[e]=b(n,t[e])})),t}(r,a.metrics),a}merge(e,t,n,r,i){var a=this.getBucket(e,t,r,i);if(a.metrics){var o=a.metrics;o.count+=n.count,(0,v.D)(n,(function(e,t){if("count"!==e){var r=o[e],i=n[e];i&&!i.c?o[e]=b(i.t,r):o[e]=function(e,t){if(!t)return e;t.c||(t=y(t.t));return t.min=Math.min(e.min,t.min),t.max=Math.max(e.max,t.max),t.t+=e.t,t.sos+=e.sos,t.c+=e.c,t}(i,o[e])}}))}else a.metrics=n}storeMetric(e,t,n,r){var i=this.getBucket(e,t,n);return i.stats=b(r,i.stats),i}getBucket(e,t,n,r){this.aggregatedData[e]||(this.aggregatedData[e]={});var i=this.aggregatedData[e][t];return i||(i=this.aggregatedData[e][t]={params:n||{}},r&&(i.custom=r)),i}get(e,t){return t?this.aggregatedData[e]&&this.aggregatedData[e][t]:this.aggregatedData[e]}take(e){for(var t={},n="",r=!1,i=0;i<e.length;i++)t[n=e[i]]=w(this.aggregatedData[n]),t[n].length&&(r=!0),delete this.aggregatedData[n];return r?t:null}}function b(e,t){return null==e?function(e){e?e.c++:e={c:1};return e}(t):t?(t.c||(t=y(t.t)),t.c+=1,t.t+=e,t.sos+=e*e,e>t.max&&(t.max=e),e<t.min&&(t.min=e),t):{t:e}}function y(e){return{t:e,min:e,max:e,sos:e*e,c:1}}function w(e){return"object"!=typeof e?[]:(0,v.D)(e,A)}function A(e,t){return t}var _=i(8632),x=i(4402),D=i(4351);var k=i(5546),E=i(7956),j=i(3239),T=i(7894),R=i(9251);class S extends f{static featureName=R.t;constructor(e,t){let n=!(arguments.length>2&&void 0!==arguments[2])||arguments[2];super(e,t,R.t,n),l.il&&((0,E.N)((()=>(0,k.p)("docHidden",[(0,T.z)()],void 0,R.t,this.ee)),!0),(0,j.bP)("pagehide",(()=>(0,k.p)("winPagehide",[(0,T.z)()],void 0,R.t,this.ee))),this.importAggregator())}}var I=i(3081);class C extends f{static featureName=I.t9;constructor(e,t){let n=!(arguments.length>2&&void 0!==arguments[2])||arguments[2];super(e,t,I.t9,n),this.importAggregator()}}new class extends t{constructor(t){let n=arguments.length>1&&void 0!==arguments[1]?arguments[1]:(0,x.ky)(16);super(),l._A?(this.agentIdentifier=n,this.sharedAggregator=new m({agentIdentifier:this.agentIdentifier}),this.features={},(0,_.h5)(n,this),this.desiredFeatures=new Set(t.features||[]),this.desiredFeatures.add(p),(0,s.j)(this,t,t.loaderType||"agent"),this.run()):(0,e.Z)("Failed to initial the agent. Could not determine the runtime environment.")}get config(){return{info:(0,r.C5)(this.agentIdentifier),init:(0,r.P_)(this.agentIdentifier),loader_config:(0,r.DL)(this.agentIdentifier),runtime:(0,r.OP)(this.agentIdentifier)}}run(){try{const t=o(this.agentIdentifier),r=[...this.desiredFeatures];r.sort(((e,t)=>n.p[e.featureName]-n.p[t.featureName])),r.forEach((r=>{if(t[r.featureName]||r.featureName===n.D.pageViewEvent){const i=function(e){switch(e){case n.D.ajax:return[n.D.jserrors];case n.D.sessionTrace:return[n.D.ajax,n.D.pageViewEvent];case n.D.sessionReplay:return[n.D.sessionTrace];case n.D.pageViewTiming:return[n.D.pageViewEvent];default:return[]}}(r.featureName);i.every((e=>t[e]))||(0,e.Z)("".concat(r.featureName," is enabled but one or more dependent features has been disabled (").concat((0,D.P)(i),"). This may cause unintended consequences or missing data...")),this.features[r.featureName]=new r(this.agentIdentifier,this.sharedAggregator)}}))}catch(t){(0,e.Z)("Failed to initialize all enabled instrument classes (agent aborted) -",t);for(const e in this.features)this.features[e].abortHandler?.();const n=(0,_.fP)();return delete n.initializedAgents[this.agentIdentifier]?.api,delete n.initializedAgents[this.agentIdentifier]?.features,delete this.sharedAggregator,n.ee?.abort(),delete n.ee?.get(this.agentIdentifier),!1}}addToTrace(t){(0,e.Z)("Call to agent api addToTrace failed. The session trace feature is not currently initialized.")}setCurrentRouteName(t){(0,e.Z)("Call to agent api setCurrentRouteName failed. The spa feature is not currently initialized.")}interaction(){(0,e.Z)("Call to agent api interaction failed. The spa feature is not currently initialized.")}}({features:[p,S,C],loaderType:"lite"})})()})();</script> <noscript><style>form.antibot * :not(.antibot-message) { display: none !important; }</style> </noscript><script async src="https://web.archive.org/web/20231128043039js_/https://www.googletagmanager.com/gtag/js?id=G-HEQ0YF2VYL"></script> <script>window.dataLayer = window.dataLayer || [];function gtag(){dataLayer.push(arguments)};gtag("js", new Date());gtag("set", "developer_id.dMDhkMT", true);gtag('set', {'cookie_flags': 'SameSite=None;Secure', 'cookie_domain': 'www.nist.gov'});gtag("config", "G-HEQ0YF2VYL", {"groups":"default","page_placeholder":"PLACEHOLDER_page_location","link_attribution":true,"allow_ad_personalization_signals":false});gtag("event", "custom", {"node_title":"SRM Definitions","node_id":"429796","content_type":"Basic page"});</script> <meta name="description" content="Reference Material (RM) - Material, sufficiently homogeneous and stable with respect to one or more specified properties"/> <link rel="canonical" href="https://web.archive.org/web/20231128043039/https://www.nist.gov/srm/srm-definitions"/> <link rel="shortlink" href="https://web.archive.org/web/20231128043039/https://www.nist.gov/node/429796"/> <meta name="citation_title" content="SRM Definitions | NIST"/> <meta property="og:site_name" content="NIST"/> <meta property="og:type" content="Article"/> <meta property="og:url" content="https://web.archive.org/web/20231128043039/https://www.nist.gov/srm/srm-definitions"/> <meta property="og:title" content="SRM Definitions"/> <meta property="og:description" content="Reference Material (RM) - Material, sufficiently homogeneous and stable with respect to one or more specified properties"/> <meta property="article:published_time" content="2010-08-11T08:56-04:00"/> <meta property="article:modified_time" content="2023-01-12T08:44-05:00"/> <meta name="dcterms.title" content="SRM Definitions"/> <meta name="dcterms.description" content="Reference Material (RM) - Material, sufficiently homogeneous and stable with respect to one or more specified properties"/> <meta name="dcterms.date" content="2010-08-11T08:56-04:00"/> <meta name="dcterms.type" content="text"/> <meta name="dcterms.format" content="text/html"/> <meta name="dcterms.identifier" content="https://www.nist.gov/srm/srm-definitions"/> <meta name="dcterms.source" content="NIST"/> <meta name="dcterms.created" content="2010-08-11T08:56-04:00"/> <meta name="dcterms.modified" content="2023-01-12T08:44-05:00"/> <meta name="twitter:card" content="summary_large_image"/> <meta name="twitter:description" content="Reference Material (RM) - Material, sufficiently homogeneous and stable with respect to one or more specified properties"/> <meta name="twitter:site" content="NIST"/> <meta name="twitter:title" content="SRM Definitions"/> <meta name="twitter:url" content="https://web.archive.org/web/20231128043039im_/https://www.nist.gov/srm/srm-definitions"/> <meta name="google-site-verification" content="QMu0ODkER3rN5hLcMLqNVf7e3bkjYsNLTuhqfH48jCA"/> <meta name="Generator" content="Drupal 10 (https://www.drupal.org)"/> <meta name="MobileOptimized" content="width"/> <meta name="HandheldFriendly" content="true"/> <meta name="viewport" content="width=device-width, initial-scale=1.0"/> <meta name="nist_search_modified" class="elastic" content="2023-01-12T08:44:00-05:00"/> <script type="application/ld+json">{ "@context": "https://web.archive.org/web/20231128043039/https://schema.org", "@graph": [ { "@type": "Article", "headline": "SRM Definitions | NIST", "description": "Reference Material (RM) - Material, sufficiently homogeneous and stable with respect to one or more specified properties", "datePublished": "2010-08-11T08:56-04:00", "dateModified": "2023-01-12T08:44-05:00" } ] }</script> <meta name="nist_search_bundle" class="elastic" content="page"/> <link rel="icon" href="/web/20231128043039im_/https://www.nist.gov/themes/custom/nist_www/favicon.ico" type="image/vnd.microsoft.icon"/> <title>SRM Definitions | NIST</title> <link rel="stylesheet" media="all" href="/web/20231128043039cs_/https://www.nist.gov/sites/default/files/css/css_-7wEAtQCSeY8x-JH_WeQTsSOBDQUBSs6FCPcv3Z5F0c.css?delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJx1TgFuwzAI_JBXnoSIzVJaHFLjNMvvZ6fdFnWqhBB3nO4uWmG43BYuWxgoXrFamxkON1787UuiTWE0G5WRJtKtSnR4JcIkXlFlukrFT9HKBf5TONJD6FJZ8lzszvBK9DI7V8-cuXUwHahgtgRJnIYW202Db145t67Oux5GtYH0eH88reDMlLj8QFzX9ag-4C7hr9oDIJVlJj09YXCLQoqZk1BPlfjwzhKL9f7hLrw67PvU6i7Kf_a_qm-61Z2S"/> <link rel="stylesheet" media="all" href="/web/20231128043039cs_/https://www.nist.gov/sites/default/files/css/css_6prwlieMvitJqVLptJ59w_NxX2prM0abXhYVoH12prk.css?delta=1&amp;language=en&amp;theme=nist_www&amp;include=eJx1TgFuwzAI_JBXnoSIzVJaHFLjNMvvZ6fdFnWqhBB3nO4uWmG43BYuWxgoXrFamxkON1787UuiTWE0G5WRJtKtSnR4JcIkXlFlukrFT9HKBf5TONJD6FJZ8lzszvBK9DI7V8-cuXUwHahgtgRJnIYW202Db145t67Oux5GtYH0eH88reDMlLj8QFzX9ag-4C7hr9oDIJVlJj09YXCLQoqZk1BPlfjwzhKL9f7hLrw67PvU6i7Kf_a_qm-61Z2S"/> <link rel="stylesheet" media="print" href="/web/20231128043039cs_/https://www.nist.gov/sites/default/files/css/css_6MuKXqcH69mMwmOSjiD2G_c6UXIqUTZ1TRnur95k7Qk.css?delta=2&amp;language=en&amp;theme=nist_www&amp;include=eJx1TgFuwzAI_JBXnoSIzVJaHFLjNMvvZ6fdFnWqhBB3nO4uWmG43BYuWxgoXrFamxkON1787UuiTWE0G5WRJtKtSnR4JcIkXlFlukrFT9HKBf5TONJD6FJZ8lzszvBK9DI7V8-cuXUwHahgtgRJnIYW202Db145t67Oux5GtYH0eH88reDMlLj8QFzX9ag-4C7hr9oDIJVlJj09YXCLQoqZk1BPlfjwzhKL9f7hLrw67PvU6i7Kf_a_qm-61Z2S"/> <link rel="stylesheet" media="all" href="/web/20231128043039cs_/https://www.nist.gov/sites/default/files/css/css_zxDJPMpCfrT8NQEavjogRlrVmShwu9oesPd2F7606bk.css?delta=3&amp;language=en&amp;theme=nist_www&amp;include=eJx1TgFuwzAI_JBXnoSIzVJaHFLjNMvvZ6fdFnWqhBB3nO4uWmG43BYuWxgoXrFamxkON1787UuiTWE0G5WRJtKtSnR4JcIkXlFlukrFT9HKBf5TONJD6FJZ8lzszvBK9DI7V8-cuXUwHahgtgRJnIYW202Db145t67Oux5GtYH0eH88reDMlLj8QFzX9ag-4C7hr9oDIJVlJj09YXCLQoqZk1BPlfjwzhKL9f7hLrw67PvU6i7Kf_a_qm-61Z2S"/> <script src="/web/20231128043039js_/https://www.nist.gov/sites/default/files/js/js_3ssAdmvsW-btol8ydZT2eloQN8l11yuGacOobfI1-_0.js?scope=header&amp;delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJx1TgFuwzAI_JBXnoSIzVJaHFLjNMvvZ6fdFnWqhBB3nO4uWmG43BYuWxgoXrFamxkON1787UuiTWE0G5WRJtKtSnR4JcIkXlFlukrFT9HKBf5TONJD6FJZ8lzszvBK9DI7V8-cuXUwHahgtgRJnIYW202Db145t67Oux5GtYH0eH88reDMlLj8QFzX9ag-4C7hr9oDIJVlJj09YXCLQoqZk1BPlfjwzhKL9f7hLrw67PvU6i7Kf_a_qm-61Z2S"></script> </head> <body class="node-429796"> <a href="#main-content" class="visually-hidden focusable" data-elastic-exclude> Skip to main content </a> <div class="dialog-off-canvas-main-canvas" data-off-canvas-main-canvas> <!-- nist-index-ignore-start --> <section data-elastic-exclude class="usa-banner" aria-label="Official government website"> <div class="usa-accordion"> <header class="usa-banner__header"> <div class="usa-banner__inner"> <div class="grid-col-auto"> <img class="usa-banner__header-flag" src="/web/20231128043039im_/https://www.nist.gov/libraries/nist-component-library/dist/img/us_flag_small.png" alt="U.S. flag"> </div> <div class="grid-col-fill tablet:grid-col-auto"> <p class="usa-banner__header-text">An official website of the United States government</p> <p class="usa-banner__header-action" aria-hidden="true">Here’s how you know</p> </div> <button class="usa-accordion__button usa-banner__button" aria-expanded="false" aria-controls="gov-banner-default"> <span class="usa-banner__button-text">Here’s how you know</span> </button> </div> </header> <div class="usa-banner__content usa-accordion__content" id="gov-banner-default"> <div class="grid-row grid-gap-lg"> <div class="usa-banner__guidance tablet:grid-col-6"> <img class="usa-banner__icon usa-media-block__img" src="/web/20231128043039im_/https://www.nist.gov/libraries/nist-component-library/dist/img/icon-dot-gov.svg" role="img" alt="" aria-hidden="true"> <div class="usa-media-block__body"> <p> <strong>Official websites use .gov</strong> <br/> A <strong>.gov</strong> website belongs to an official government organization in the United States. </p> </div> </div> <div class="usa-banner__guidance tablet:grid-col-6"> <img class="usa-banner__icon usa-media-block__img" src="/web/20231128043039im_/https://www.nist.gov/libraries/nist-component-library/dist/img/icon-https.svg" role="img" alt="" aria-hidden="true"> <div class="usa-media-block__body"> <p> <strong>Secure .gov websites use HTTPS</strong> <br/> A <strong>lock</strong> ( <span class="icon-lock"> <svg xmlns="http://www.w3.org/2000/svg" width="52" height="64" viewbox="0 0 52 64" class="usa-banner__lock-image" role="img" aria-labelledby="banner-lock-title banner-lock-description" focusable="false"> <title id="banner-lock-title">Lock</title> <desc id="banner-lock-description">A locked padlock</desc><path fill="#000000" fill-rule="evenodd" d="M26 0c10.493 0 19 8.507 19 19v9h3a4 4 0 0 1 4 4v28a4 4 0 0 1-4 4H4a4 4 0 0 1-4-4V32a4 4 0 0 1 4-4h3v-9C7 8.507 15.507 0 26 0zm0 8c-5.979 0-10.843 4.77-10.996 10.712L15 19v9h22v-9c0-6.075-4.925-11-11-11z"/></svg> </span> ) or <strong>https://</strong> means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites. </p> </div> </div> </div> </div> </div> </section> <!-- nist-index-ignore-end --> <div data-elastic-exclude> <!-- nist-index-ignore-start --> <div class="nist-print-header" style="display:none;"> <p class="nist-print-header__url">https://www.nist.gov/srm/srm-definitions</p> <img class="nist-print-header__logo" width="289" height="38" src="/web/20231128043039im_/https://www.nist.gov/libraries/nist-component-library/dist/img/logo/nist_logo_sidestack.svg" alt="National Institute of Standards and Technology"/> </div> <div class="usa-overlay"></div> <header class="usa-header nist-header--www nist-header--minimal" role="banner"> <div class="usa-navbar"> <div class="usa-logo flex-fill"> <a href="/web/20231128043039/https://www.nist.gov/" title="National Institute of Standards and Technology" aria-label="Home"> <img src="/web/20231128043039im_/https://www.nist.gov/libraries/nist-component-library/dist/img/logo/logo.svg" alt="National Institute of Standards and Technology" width="300px" height="80px"/> </a> </div> <div class="usa-header__right grid-row flex-auto"> <div class="grid-col-fill nist-header__search-group"> <form class="usa-search usa-search--small" accept-charset="UTF-8" action="/web/20231128043039/https://www.nist.gov/search" id="search_form" method="get"> <div role="search"> <label class="usa-sr-only" for="search-form">Search NIST</label> <input class="usa-input" id="search-form" type="search" name="s" placeholder="Search NIST" required="" maxlength="128"> <button class="usa-button" type="submit"><img src="/web/20231128043039im_/https://www.nist.gov/libraries/nist-component-library/dist/img/usa-icons-bg/search--white.svg" class="usa-search__submit-icon" alt="Search"></button> </div> </form> </div> <div class="grid-col-auto padding-left-1"> <button class="usa-menu-btn">Menu</button> </div> </div> </div> <nav aria-label="Primary navigation" class="usa-nav"> <div class="usa-nav__inner"> <button class="usa-nav__close">Close</button> <ul class="usa-nav__primary usa-accordion"> <li class="usa-nav__primary-item"> <button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-1"><span>Topics</span></button> <div id="primary_menu-1" class="usa-nav__submenu usa-megamenu"> <div class="grid-row"> <div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/topics" class="usa-nav__link">All Topics</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/advanced-communications" class="usa-nav__link">Advanced communications</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/artificial-intelligence" class="usa-nav__link">Artificial intelligence</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/bioscience" class="usa-nav__link">Bioscience</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/buildings-construction" class="usa-nav__link">Buildings and construction</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/chemistry" class="usa-nav__link">Chemistry</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/climate" class="usa-nav__link">Climate</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/cybersecurity" class="usa-nav__link">Cybersecurity</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/electronics" class="usa-nav__link">Electronics</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/energy" class="usa-nav__link">Energy</a> </li> </ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/environment" class="usa-nav__link">Environment</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/fire" class="usa-nav__link">Fire</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/forensic-science" class="usa-nav__link">Forensic science</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/health" class="usa-nav__link">Health</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/information-technology" class="usa-nav__link">Information technology</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/infrastructure" class="usa-nav__link">Infrastructure</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/manufacturing" class="usa-nav__link">Manufacturing</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/materials" class="usa-nav__link">Materials</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/mathematics-statistics" class="usa-nav__link">Mathematics and statistics</a> </li> </ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/metrology" class="usa-nav__link">Metrology</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/nanotechnology" class="usa-nav__link">Nanotechnology</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/neutron-research" class="usa-nav__link">Neutron research</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/performance-excellence" class="usa-nav__link">Performance excellence</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/physics" class="usa-nav__link">Physics</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/public-safety" class="usa-nav__link">Public safety</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/resilience" class="usa-nav__link">Resilience</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/standards" class="usa-nav__link">Standards</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/transportation" class="usa-nav__link">Transportation</a> </li> </ul> </div> </div> </div> </li> <li class="usa-nav__primary-item"> <a class="usa-nav__link" href="/web/20231128043039/https://www.nist.gov/publications">Publications</a> </li> <li class="usa-nav__primary-item"> <button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-3"><span>Labs &amp; Major Programs</span></button> <div id="primary_menu-3" class="usa-nav__submenu usa-megamenu"> <div class="grid-row"> <div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/labs-major-programs/laboratories" class="usa-nav__link">Laboratories</a> <ul class="usa-nav__submenu-list"> <li> <a href="/web/20231128043039/https://www.nist.gov/ctl" class="usa-nav__link">Communications Technology Laboratory</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/el" class="usa-nav__link">Engineering Laboratory</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/itl" class="usa-nav__link">Information Technology Laboratory</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/mml" class="usa-nav__link">Material Measurement Laboratory</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/pml" class="usa-nav__link">Physical Measurement Laboratory</a> </li> </ul> </li> </ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/labs-major-programs/user-facilities" class="usa-nav__link">User Facilities</a> <ul class="usa-nav__submenu-list"> <li> <a href="/web/20231128043039/https://www.nist.gov/ncnr" class="usa-nav__link">NIST Center for Neutron Research</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/cnst" class="usa-nav__link">CNST NanoFab</a> </li> </ul> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/labs-major-programs/research-test-beds" class="usa-nav__link">Research Test Beds</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/laboratories/projects-programs" class="usa-nav__link">Research Projects</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/laboratories/tools-instruments" class="usa-nav__link">Tools &amp; Instruments</a> </li> </ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/labs-major-programs/major-programs" class="usa-nav__link">Major Programs</a> <ul class="usa-nav__submenu-list"> <li> <a href="/web/20231128043039/https://www.nist.gov/baldrige" class="usa-nav__link">Baldrige Performance Excellence Program</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/chips" class="usa-nav__link">CHIPS for America Initiative</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/mep" class="usa-nav__link">Manufacturing Extension Partnership (MEP)</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/oam" class="usa-nav__link">Office of Advanced Manufacturing</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/spo" class="usa-nav__link">Special Programs Office</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/tpo" class="usa-nav__link">Technology Partnerships Office</a> </li> </ul> </li> </ul> </div> </div> </div> </li> <li class="usa-nav__primary-item"> <button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-4"><span>Services &amp; Resources</span></button> <div id="primary_menu-4" class="usa-nav__submenu usa-megamenu"> <div class="grid-row"> <div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/services-resources/standards-and-measurements" class="usa-nav__link">Standards and Measurements</a> <ul class="usa-nav__submenu-list"> <li> <a href="/web/20231128043039/https://www.nist.gov/calibrations" class="usa-nav__link">Calibration Services</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/nvlap" class="usa-nav__link">Laboratory Accreditation (NVLAP)</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/nist-quality-system" class="usa-nav__link">Quality System</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/srm" class="usa-nav__link">Standard Reference Materials (SRMs)</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/standardsgov" class="usa-nav__link">Standards.gov</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/pml/time-and-frequency-division/time-services" class="usa-nav__link">Time Services</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/pml/owm" class="usa-nav__link">Office of Weights and Measures</a> </li> </ul> </li> </ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/services-resources/software" class="usa-nav__link">Software</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/data" class="usa-nav__link">Data</a> <ul class="usa-nav__submenu-list"> <li> <a href="https://web.archive.org/web/20231128043039/https://webbook.nist.gov/chemistry/" class="usa-nav__link">Chemistry WebBook</a> </li> <li> <a href="https://web.archive.org/web/20231128043039/https://nvd.nist.gov/" class="usa-nav__link">National Vulnerability Database</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/pml/productsservices/physical-reference-data" class="usa-nav__link">Physical Reference Data</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/srd" class="usa-nav__link">Standard Reference Data (SRD)</a> </li> </ul> </li> <li class="usa-nav__submenu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/shop" class="usa-nav__link">Storefront</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/tpo" class="usa-nav__link">License &amp; Patents</a> </li> </ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="https://web.archive.org/web/20231128043039/https://csrc.nist.gov/" class="usa-nav__link">Computer Security Resource Center (CSRC)</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/nist-research-library" class="usa-nav__link">NIST Research Library</a> </li> </ul> </div> </div> </div> </li> <li class="usa-nav__primary-item"> <button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-5"><span>News &amp; Events</span></button> <div id="primary_menu-5" class="usa-nav__submenu usa-megamenu"> <div class="grid-row"> <div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/news-events/news" class="usa-nav__link">News</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/news-events/events" class="usa-nav__link">Events</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/blogs" class="usa-nav__link">Blogs</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/feature-stories" class="usa-nav__link">Feature Stories</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/awards" class="usa-nav__link">Awards</a> </li> </ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/video-gallery" class="usa-nav__link">Video Gallery</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/image-gallery" class="usa-nav__link">Image Gallery</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/pao/media-contacts" class="usa-nav__link">Media Contacts</a> </li> </ul> </div> </div> </div> </li> <li class="usa-nav__primary-item"> <button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-6"><span>About NIST</span></button> <div id="primary_menu-6" class="usa-nav__submenu usa-megamenu"> <div class="grid-row"> <div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/about-nist" class="usa-nav__link">About Us</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/about-nist/contact-us" class="usa-nav__link">Contact Us</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/about-nist/visit" class="usa-nav__link">Visit</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/careers" class="usa-nav__link">Careers</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/director/nist-organization-structure" class="usa-nav__link">Our Organization</a> <ul class="usa-nav__submenu-list"> <li> <a href="/web/20231128043039/https://www.nist.gov/director" class="usa-nav__link">Office of the Director</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/director/nist-organization-structure/budget-planning" class="usa-nav__link">Budget &amp; Planning</a> </li> </ul> </li> </ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list"> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/about-nist/work-nist" class="usa-nav__link">Work with NIST</a> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/history" class="usa-nav__link">History</a> <ul class="usa-nav__submenu-list"> <li> <a href="https://web.archive.org/web/20231128043039/http://nistdigitalarchives.contentdm.oclc.org/" class="usa-nav__link">NIST Digital Archives</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/nist-museum" class="usa-nav__link">NIST Museum</a> </li> <li> <a href="/web/20231128043039/https://www.nist.gov/nist-and-nobel" class="usa-nav__link">NIST and the Nobel</a> </li> </ul> </li> <li class="usa-nav__submenu-item"> <a href="/web/20231128043039/https://www.nist.gov/education" class="usa-nav__link">Educational Resources</a> </li> </ul> </div> </div> </div> </li> </ul> </div> </nav> </header> <!-- nist-index-ignore-end --> </div> <div class="grid-container"> <div data-drupal-messages-fallback class="hidden"></div> </div> <div id="block-nist-www-content" class="nist-block"> <section class="nist-page__content usa-section clearfix"> <a id="main-content" tabindex="-1"></a> <div class="nist-page__region nist-page__region--content-top-full"> <div class="nist-block"> <div class="nist-section-header nist-section-header--419246 nist-section-header--menu nist-section-header--interior"> <div class="nist-section-header__main grid-container"> <div class="nist-section-header__title"> <h2><a href="/web/20231128043039/https://www.nist.gov/srm">Standard Reference Materials</a></h2> </div> </div> </div> </div> </div> <div class="grid-container margin-top-4"> <div class="grid-row grid-gap-6"> <aside class="nist-page__region nist-page__region--sidebar-first tablet-lg:grid-col-4 desktop-lg:grid-col-3"> <div> <!-- nist-index-ignore-start --> <div class="views-element-container nist-block nist-block--section-nav" data-elastic-exclude=""> <div><div class="js-view-dom-id-38182354b97bdd2d0e812fd86a3a58463f053145628273a17cfd3ee508b58f50"> <div><div class="views-field views-field-nid"><span class="field-content"> <nav> <ul class="usa-sidenav usa-accordion "> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/about-nist-srms" data-drupal-link-system-path="">About NIST SRMs</a> </li> <li class="usa-sidenav__item usa-sidenav__item--parent"> <a href="/web/20231128043039/https://www.nist.gov/srm/ordering-policies-and-pricing" data-drupal-link-system-path="">Ordering Policies and Pricing</a> <button class="usa-accordion__button" aria-expanded="false" aria-controls="menu-standard-reference-material-2"><span class="usa-sr-only">Expand or Collapse</span></button> <ul id="menu-standard-reference-material-2" class="usa-sidenav__sublist usa-accordion"> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/ordering-policies-and-pricing/sales-and-customer-service" data-drupal-link-system-path="">Sales and Customer Service</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/ordering-policies-and-pricing/terms-and-conditions" data-drupal-link-system-path="">Terms and Conditions</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/ordering-policies-and-pricing/pricing-policy" data-drupal-link-system-path="">Pricing Policy</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/document/prepaymentpolicyonnistsrmorders5292018pdf" data-drupal-link-system-path="">Payment Policy</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/ordering-policies-and-pricing/ordering-policies" data-drupal-link-system-path="">Ordering Policies</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/ordering-policies-and-pricing/required-ordering-information" data-drupal-link-system-path="">Required Ordering Information</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/ordering-policies-and-pricing/order-discrepancies-and-returned-goods" data-drupal-link-system-path="">Order Discrepancies and Returned Goods</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/ordering-policies-and-pricing/shipping-information" data-drupal-link-system-path="">Shipping Information</a> </li> </ul> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/licensed-distributors" data-drupal-link-system-path="">Licensed Distributors</a> </li> <li class="usa-sidenav__item usa-sidenav__item--parent"> <a href="/web/20231128043039/https://www.nist.gov/srm/registration-and-surveys" data-drupal-link-system-path="">Registration and Surveys</a> <button class="usa-accordion__button" aria-expanded="false" aria-controls="menu-standard-reference-material-4"><span class="usa-sr-only">Expand or Collapse</span></button> <ul id="menu-standard-reference-material-4" class="usa-sidenav__sublist usa-accordion"> <li class="usa-sidenav__item"> <a href="https://web.archive.org/web/20231128043039/https://www.surveymonkey.com/r/srm_reg" data-drupal-link-system-path="">Register Your SRM</a> </li> <li class="usa-sidenav__item"> <a href="https://web.archive.org/web/20231128043039/https://www.surveymonkey.com/r/nistsrm_product" data-drupal-link-system-path="">Product Survey</a> </li> <li class="usa-sidenav__item"> <a href="https://web.archive.org/web/20231128043039/https://www.surveymonkey.com/r/nistsrm_survey" data-drupal-link-system-path="">Customer Service Survey</a> </li> </ul> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/using-online-catalog" data-drupal-link-system-path="">Using the Online Catalog</a> </li> <li class="usa-sidenav__item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/srm/srm-frequently-asked-questions" data-drupal-link-system-path="">SRM Frequently Asked Questions</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/srm-exhibits" data-drupal-link-system-path="">SRM Exhibits</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/srm-definitions" class="usa-current" data-drupal-link-system-path="">SRM Definitions</a> </li> <li class="usa-sidenav__item"> <a href="https://web.archive.org/web/20231128043039/https://shop.nist.gov/ccrz__CCPage?pageKey=SRMCategory&amp;cclcl=en_US%29" data-drupal-link-system-path="">Tables of SRM Categories</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/how-cite-nist-srm" data-drupal-link-system-path="">How to Cite a NIST SRM</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/document/measurement-services-policy-letter" data-drupal-link-system-path="">Measurement Services Policy Letter</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/calibrations/traceability" data-drupal-link-system-path="">NIST Policy on Metrological Traceability</a> </li> <li class="usa-sidenav__item"> <a href="https://web.archive.org/web/20231128043039/https://pages.nist.gov/NIST-Tech-Pubs/SP260.html" data-drupal-link-system-path="">Publications (SP260s)</a> </li> <li class="usa-sidenav__item"> <a href="https://web.archive.org/web/20231128043039/https://shop.nist.gov/ccrz__CCPage?pageKey=SRMArchive&amp;cclcl=en_US" data-drupal-link-system-path="">Archived SRM/RM Certificates/Reports of Investigation</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/srm/new-srmsrms" data-drupal-link-system-path="">New SRMs/RMs</a> </li> <li class="usa-sidenav__item"> <a href="/web/20231128043039/https://www.nist.gov/sri" data-drupal-link-system-path="">Standard Reference Instruments</a> </li> <li class="usa-sidenav__item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/nist-quality-system" title="NIST Quality System" data-drupal-link-system-path="">NIST Quality System</a> </li> </ul> </nav> </span></div></div> </div> </div> </div> <!-- nist-index-ignore-end --> <!-- nist-index-ignore-start --> <!-- nist-index-ignore-end --> </div> </aside> <div class="nist-page__region nist-page__region--content tablet-lg:grid-col-8 desktop-lg:grid-col-9"> <div class="nist-block"> <h1 class="nist-page__title">SRM Definitions</h1> </div> <div class="nist-block"> <!-- nist-index-ignore-start --> <div data-elastic-exclude class="nist-block nist-social__wrapper"> <h2 class="nist-social__title">Share</h2> <div class="social-media-sharing"> <div class="nist-social__wrapper--share"> <div> <a target="_blank" rel="noopener" href="https://web.archive.org/web/20231128043039/https://www.facebook.com/share.php?u=https://www.nist.gov/srm/srm-definitions" title="Facebook" class="nist-social nist-social--facebook-gray"> <span>Facebook</span> </a> </div> <div> <a target="_blank" rel="noopener" href="https://web.archive.org/web/20231128043039/https://www.linkedin.com/shareArticle?mini=true&amp;url=https://www.nist.gov/srm/srm-definitions&amp;source=https://www.nist.gov/srm/srm-definitions" title="Linkedin" class="nist-social nist-social--linkedin-gray"> <span>Linkedin</span> </a> </div> <div> <a target="_blank" rel="noopener" href="https://web.archive.org/web/20231128043039/https://twitter.com/intent/tweet?url=https://www.nist.gov/srm/srm-definitions&amp;status=https://www.nist.gov/srm/srm-definitions" title="Twitter" class="nist-social nist-social--twitter-gray"> <span>Twitter</span> </a> </div> <div> <a href="https://web.archive.org/web/20231128043039/mailto:/?subject=NIST.gov&amp;body=Check out this site https://www.nist.gov/srm/srm-definitions" title="Email" class="nist-social nist-social--envelope-gray"> <span>Email</span> </a> </div> </div> </div> </div> <!-- nist-index-ignore-end --> </div> <div class="nist-block"> <div class="text-with-summary"> <p><strong>Reference Material (RM)</strong> - Material, sufficiently homogeneous and stable with respect to one or more specified properties, which has been established to be fit for its intended use in a measurement process</p> <ol><li> <p>RM is a generic term.</p> </li> <li> <p>Properties can be quantitative or qualitative, e.g. identity of substances or species.</p> </li> <li> <p>Uses may include the calibration of a measurement system, assessment of a measurement procedure, assigning values to other materials, and quality control.</p> </li> <li> <p>A single RM cannot be used for both calibration and validation of results in the same measurement procedure.</p> </li> <li> <p>International Vocabulary of Metrology – Basic and General Concepts and Associated Terms has an analogous definition (VIM - ISO/IEC Guide 99:2007, 5.13), but restricts the term "measurement" to apply to quantitative values and not to qualitative properties. However, Note 3 of ISO/IEC Guide 99:2007, 5.13, specifically includes the concept of qualitative attributes, called "nominal properties".</p> </li> </ol><p>(ISO Guide 30:1992/Amd 1:2008)</p> <p><strong>Certified Reference Material (CRM)</strong> - Reference material characterized by a metrologically valid procedure for one or more specified properties, accompanied by a certificate that provides the value of the specified property, its associated uncertainty, and a statement of metrological traceability</p> <ol><li> <p>The concept of value includes qualitative attributes such as identity or sequence. Uncertainties for such attributes may be expressed as probabilities.</p> </li> <li> <p>Metrologically valid procedures for the production and certification of reference materials are given in, among others, ISO Guides 34 and 35.</p> </li> <li> <p>ISO Guide 31 gives guidance on the contents of certificates.</p> </li> <li> <p>VIM has an analogous definition (ISO/IEC Guide 99:2007, 5.14).</p> </li> </ol><p>(ISO Guide 30:1992/Amd 1:2008)</p> <p><strong>Reference Material Certificate</strong> - Document accompanying a certified reference material stating one or more property values and their uncertainties, and confirming that the necessary procedures have been carried out to ensure their validity and traceability. (ISO Guide 30: 1992)</p> <p><strong>NIST Standard Reference Material® (SRM)</strong> - A CRM issued by NIST that also meets additional NIST-specific certification criteria and is issued with a certificate or certificate of analysis that reports the results of its characterizations and provides information regarding the appropriate use(s) of the material (NIST SP 260-136). Note: An SRM is prepared and used for three main purposes: (1) to help develop accurate methods of analysis; (2) to calibrate measurement systems used to facilitate exchange of goods, institute quality control, determine performance characteristics, or measure a property at the state-of-the-art limit; and (3) to ensure the long-term adequacy and integrity of measurement quality assurance programs. The term "Standard Reference Material" is registered with the United States Patent and Trademark Office.</p> <p><strong>NIST Reference Material</strong> - Material issued by NIST with a report of investigation instead of a certificate to: (1) further scientific or technical research; (2) determine the efficacy of a prototype reference material; (3) provide a homogeneous and stable material so that investigators in different laboratories can be ensured that they are investigating the same material; and (4) ensure availability when a material produced and certified by an organization other than NIST is defined to be in the public interest or when an alternate means of national distribution does not exist. A NIST RM meets the ISO definition for a RM and may meet the ISO definition for a CRM (depending on the organization that produced it).</p> <p><span><span><strong><a name="rgtm" id="rgtm"></a>NIST Research Grade Test Material (RGTM)</strong> - A material evaluated during the SRM/RM development phase.  RGTMs may be distributed in a NIST-sponsored interlaboratory inter-comparison to determine the fit for purpose of the candidate SRM/RM material.  It is prepared to be homogeneous and stable but typically has not been quantitatively evaluated for all properties of potential interest.</span></span></p> <p><strong>NIST Traceable Reference Material<sup>TM</sup>(NTRM<sup>TM</sup>)</strong> - A commercially-produced reference material with a well-defined traceability linkage to existing NIST standards for chemical measurements. This traceability linkage is established via criteria and protocols defined by NIST to meet the needs of the metrological community to be served (NIST SP 260-136). Reference materials producers adhering to these requirements are allowed use of the NTRM trademark. A NIST NTRM may be recognized by a regulatory authority as being equivalent to a CRM .</p> <p><strong>NIST Certified Value</strong> - A value reported on an SRM certificate or certificate of analysis for which NIST has the highest confidence in its accuracy in that all known or suspected sources of bias have been fully investigated or accounted for by NIST. (NIST SP 260-136)</p> <p><strong>NIST Reference Value</strong> - A best estimate of the true value provided on a NIST certificate, certificate of analysis, or report of investigation where all known or suspected sources of bias have not been fully investigated by NIST. (NIST SP 260-136)</p> <p><strong>NIST SRM Certificate or Certificate of Analysis</strong> - In accordance with ISO Guide 31: 2000, a NIST SRM certificate is a document containing the name, description, and intended purpose of the material, the logo of the U.S. Department of Commerce, the name of NIST as a certifying body, instructions for proper use and storage of the material, certified property value(s) with associated uncertainty(ies), method(s) used to obtain property values, the period of validity, if appropriate, and any other technical information deemed necessary for its proper use. A Certificate is issued for an SRM certified for one or more specific physical or engineering performance properties and may contain NIST reference, information, or both values in addition to certified values. A Certificate of Analysis is issued for an SRM certified for one or more specific chemical properties. Note: ISO Guide 31 is updated periodically; check with ISO for the latest version.</p> <p><strong>NIST Certificate of Traceability</strong> - Document stating the purpose, protocols, and measurement pathways that support claims by an NTRM to specific NIST standards or stated references. No NIST certified values are provided, but rather the document references a specific NIST report of analysis, bears the logo of the U.S. Department of Commerce, the name of NIST as a certifying body, and the name and title of the NIST officer authorized to accept responsibility for its contents.</p> <p><strong>NIST RM Report of Investigation</strong> - Document issued with a NIST RM that contains all the technical information necessary for proper use of the material, the logo of the U.S. Department of Commerce, and the name and title of the NIST officer authorized to issue it. There are no NIST certified values provided, and authorship of a report's contents may be by an organization other than NIST.</p> <p><strong>NIST Report of Analysis (ROA)</strong> - Document containing the certification of the material and including such information as the base material used, how the SRM was manufactured, the certification method(s) and description of procedures, outside collaborators, instructions for use, special instructions for packaging, handling, and storage, and plan for stability testing. The ROA is intended for internal NIST use only</p> <p><strong>Status -</strong> SRM/RMs can have one the following status values:</p> <table align="center"><tbody><tr><td>Available:</td> <td>Material is available for purchase.</td> </tr><tr><td>Out of Stock:</td> <td>Item is not available at this time. You have been placed on the notification list, without committing you to a purchase. You will be notified about changes in the status of this item. (This status used to be known as "Long-Term Backorder").</td> </tr><tr><td>Discontinued:</td> <td>This product is no longer being produced</td> </tr><tr><td>Replaced by:</td> <td>This product has been replaced by the indicated SRM.</td> </tr></tbody></table><p> </p> </div> </div> <div class="nist-block"> <!-- nist-index-ignore-start --> <div data-elastic-exclude="" class="nist-tags"> <a href="/web/20231128043039/https://www.nist.gov/topic-terms/reference-materials" hreflang="en">Reference materials</a></div> <!-- nist-index-ignore-end --> </div> </div> </div> </div> <div class="grid-container"> <div class="nist-page__region nist-page__region--content-bottom"> <div class="nist-block"> <div class="text-italic font-sans-2xs"> Created August 11, 2010, Updated January 12, 2023 </div> </div> </div> </div> </section> </div> <div data-elastic-exclude> <!-- nist-index-ignore-start --> <footer class="nist-footer padding-bottom-4"> <div class="grid-container nist-footer__info"> <div class="grid-row"> <div class="tablet:grid-col-6"> <div class="nist-footer__logo"> <a href="/web/20231128043039/https://www.nist.gov/" title="National Institute of Standards and Technology" rel="home"> <img class="nist-footer__logo-img" src="/web/20231128043039im_/https://www.nist.gov/libraries/nist-component-library/dist/img/logo/NIST-Logo-Brand-White.svg" alt="National Institute of Standards and Technology logo" width="300px" height="42px"/> </a> </div> <div class="nist-footer__contact"> <h3 class="nist-footer__contact-heading">HEADQUARTERS</h3> <address> 100 Bureau Drive<br> Gaithersburg, MD 20899<br> <a href="https://web.archive.org/web/20231128043039/tel:301-975-2000">301-975-2000</a> </address> <p> <a href="https://web.archive.org/web/20231128043039/mailto:do-webmaster@nist.gov">Webmaster</a> | <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/about-nist/contact-us">Contact Us</a> | <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/visit">Our Other Offices</a> </p> </div> </div> <div class="tablet:grid-col-6"> <div class="nist-footer__social-links"> <a class="nist-social nist-social--twitter-white" href="https://web.archive.org/web/20231128043039/https://twitter.com/NIST"> <span>Twitter</span> </a> <a class="nist-social nist-social--facebook-white" href="https://web.archive.org/web/20231128043039/https://www.facebook.com/NIST"> <span>Facebook</span> </a> <a class="nist-social nist-social--linkedin-white" href="https://web.archive.org/web/20231128043039/https://www.linkedin.com/company/nist"> <span>LinkedIn</span> </a> <a class="nist-social nist-social--instagram-white" href="https://web.archive.org/web/20231128043039/https://www.instagram.com/nist/"> <span>Instagram</span> </a> <a class="nist-social nist-social--youtube-white" href="https://web.archive.org/web/20231128043039/https://www.youtube.com/NIST"> <span>YouTube</span> </a> <a class="nist-social nist-social--giphy-white" href="https://web.archive.org/web/20231128043039/https://giphy.com/nist"> <span>Giphy</span> </a> <a class="nist-social nist-social--rss-white" href="https://web.archive.org/web/20231128043039/https://www.nist.gov/news-events/nist-rss-feeds"> <span>RSS Feed</span> </a> <a class="nist-social nist-social--envelope-white" href="https://web.archive.org/web/20231128043039/https://public.govdelivery.com/accounts/USNIST/subscriber/new"> <span>Mailing List</span> </a> </div> <div class="nist-footer__feedback"> How are we doing? <a class="usa-button" rel="nofollow" href="/web/20231128043039/https://www.nist.gov/form/nist-gov-feedback?destination=/srm/srm-definitions" title="Provide feedback">Feedback</a> </div> </div> </div> </div> <div class="grid-container"> <div class="nist-footer__nav" role="navigation"> <ul> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/privacy-policy">Site Privacy</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/oism/accessibility">Accessibility</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/privacy">Privacy Program</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/oism/copyrights">Copyrights</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.commerce.gov/vulnerability-disclosure-policy">Vulnerability Disclosure</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/no-fear-act-policy">No Fear Act Policy</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/office-director/freedom-information-act">FOIA</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/environmental-policy-statement">Environmental Policy</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/summary-report-scientific-integrity">Scientific Integrity</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.nist.gov/nist-information-quality-standards">Information Quality Standards</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://www.commerce.gov/">Commerce.gov</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/http://www.science.gov/">Science.gov</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/http://www.usa.gov/">USA.gov</a> </li> <li class="nist-footer__menu-item"> <a href="https://web.archive.org/web/20231128043039/https://vote.gov/">Vote.gov</a> </li> </ul> </div> </div> </footer> <!-- nist-index-ignore-end --> </div> </div> <script type="application/json" data-drupal-selector="drupal-settings-json">{"path":{"baseUrl":"\/","scriptPath":null,"pathPrefix":"","currentPath":"node\/429796","currentPathIsAdmin":false,"isFront":false,"currentLanguage":"en"},"pluralDelimiter":"\u0003","suppressDeprecationErrors":true,"back_to_top":{"back_to_top_button_trigger":100,"back_to_top_prevent_on_mobile":false,"back_to_top_prevent_in_admin":true,"back_to_top_button_type":"image","back_to_top_button_text":"Back to top"},"google_analytics":{"account":"G-HEQ0YF2VYL","trackOutbound":true,"trackMailto":true,"trackTel":true,"trackDownload":true,"trackDownloadExtensions":"7z|aac|arc|arj|asf|asx|avi|bin|bsh|c|csv|doc(x|m)?|dot(x|m)?|dw(fx|g|gd)|dxf|eps|epub|exe|f(90)|flv|gif|gz|gzip|hqx|jar|jpe?g|js|m1v|mp(2|3|4|e?g)|mobi|mov(ie)?|msi|msp|pdf|phps|pl|png|ppt(x|m)?|pot(x|m)?|pps(x|m)?|ppam|sld(x|m)?|thmx|qtm?|ra(m|r)?|rfa|rtf|rvt|sch|sea|sit|swf|tar|tgz|tif|txt|txz|wav|wma|wmv|wpd|wrl|xls(x|m|b)?|xlt(x|m)|xlam|xml|xsd|z|zip"},"nist_search":{"clickTracking":"search-report-click","isDebug":false,"clickTrackEnabled":true,"message":"NIST Search in debug mode. Check the browsers network inspector for Click Track reporting results..."},"data":{"extlink":{"extTarget":false,"extTargetNoOverride":false,"extNofollow":false,"extNoreferrer":false,"extFollowNoOverride":false,"extClass":"ext","extLabel":"(link is external)","extImgClass":false,"extSubdomains":true,"extExclude":"\\.gov\\\/|\\.mil\\\/|\\manufacturingusa\\.com\\\/","extInclude":"","extCssExclude":"","extCssExplicit":"","extAlert":true,"extAlertText":"Thank you for visiting NIST. We hope your visit was informative. We have provided a link to this site because it has information that may be of interest to our users. NIST does not necessarily endorse the views expressed or the facts presented on this site. Further, NIST does not endorse any commercial products that may be advertised or available on this site. Click OK to be directed to your link.","mailtoClass":"0","mailtoLabel":"(link sends email)","extUseFontAwesome":false,"extIconPlacement":"append","extFaLinkClasses":"fa fa-external-link","extFaMailtoClasses":"fa fa-envelope-o","whitelistedDomains":[]}},"user":{"uid":0,"permissionsHash":"2f77e4dcfce20728ac491170886da836c10b580f9bdfeb9c9e729fe4958834d5"}}</script> <script src="/web/20231128043039js_/https://www.nist.gov/sites/default/files/js/js_wWC32cBD9qab55wFkKWKvOdi_p-P8cBjregEiEdV1z4.js?scope=footer&amp;delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJx1TgFuwzAI_JBXnoSIzVJaHFLjNMvvZ6fdFnWqhBB3nO4uWmG43BYuWxgoXrFamxkON1787UuiTWE0G5WRJtKtSnR4JcIkXlFlukrFT9HKBf5TONJD6FJZ8lzszvBK9DI7V8-cuXUwHahgtgRJnIYW202Db145t67Oux5GtYH0eH88reDMlLj8QFzX9ag-4C7hr9oDIJVlJj09YXCLQoqZk1BPlfjwzhKL9f7hLrw67PvU6i7Kf_a_qm-61Z2S"></script> <script src="https://web.archive.org/web/20231128043039js_/https://siteimproveanalytics.com/js/siteanalyze_6017546.js" async></script> <script src="/web/20231128043039js_/https://www.nist.gov/sites/default/files/js/js_os59nuR5zggldWlpN64lVOtwfILbqHxATX9Bq3PXLA8.js?scope=footer&amp;delta=2&amp;language=en&amp;theme=nist_www&amp;include=eJx1TgFuwzAI_JBXnoSIzVJaHFLjNMvvZ6fdFnWqhBB3nO4uWmG43BYuWxgoXrFamxkON1787UuiTWE0G5WRJtKtSnR4JcIkXlFlukrFT9HKBf5TONJD6FJZ8lzszvBK9DI7V8-cuXUwHahgtgRJnIYW202Db145t67Oux5GtYH0eH88reDMlLj8QFzX9ag-4C7hr9oDIJVlJj09YXCLQoqZk1BPlfjwzhKL9f7hLrw67PvU6i7Kf_a_qm-61Z2S"></script> <script type="text/javascript">window.NREUM||(NREUM={});NREUM.info={"beacon":"gov-bam.nr-data.net","licenseKey":"37b7ccb661","applicationID":"1089704227","transactionName":"YFxUN0sADEdYVkBaClkWdwBNCA1aFnFGRhVWVWoNVgUHaHpaWkcXWFVaBks9LFtdUGJaAEB6WQ1NEw1YVVBGHltBUFMU","queueTime":4,"applicationTime":688,"atts":"TBtXQQMaH0k=","errorBeacon":"gov-bam.nr-data.net","agent":""}</script></body> </html> <!-- FILE ARCHIVED ON 04:30:39 Nov 28, 2023 AND RETRIEVED FROM THE INTERNET ARCHIVE ON 10:53:32 Feb 27, 2025. JAVASCRIPT APPENDED BY WAYBACK MACHINE, COPYRIGHT INTERNET ARCHIVE. ALL OTHER CONTENT MAY ALSO BE PROTECTED BY COPYRIGHT (17 U.S.C. SECTION 108(a)(3)). --> <!-- playback timings (ms): captures_list: 0.678 exclusion.robots: 0.039 exclusion.robots.policy: 0.028 esindex: 0.01 cdx.remote: 10.636 LoadShardBlock: 201.734 (6) PetaboxLoader3.datanode: 156.365 (7) PetaboxLoader3.resolve: 167.498 (2) load_resource: 179.023 -->

Pages: 1 2 3 4 5 6 7 8 9 10