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typeof="mw:File/Thumb"><a href="/wiki/File:Radium_Dial.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/88/Radium_Dial.jpg/220px-Radium_Dial.jpg" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/88/Radium_Dial.jpg/330px-Radium_Dial.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/8/88/Radium_Dial.jpg 2x" data-file-width="340" data-file-height="340" /></a><figcaption>A 1950s radium clock, exposed to <a href="/wiki/Black_light" class="mw-redirect" title="Black light">ultraviolet light</a> to increase luminescence</figcaption></figure> <p><b>Radium dials</b> are <a href="/wiki/Watch" title="Watch">watch</a>, <a href="/wiki/Clock" title="Clock">clock</a> and other instrument <a href="/wiki/Dial_(measurement)" title="Dial (measurement)">dials</a> painted with <a href="/wiki/Luminous_paint" title="Luminous paint">luminous paint</a> containing <a href="/wiki/Radium-226" title="Radium-226">radium-226</a> to produce <a href="/wiki/Radioluminescence" title="Radioluminescence">radioluminescence</a>. Radium dials were produced throughout most of the 20th century before being replaced by safer <a href="/wiki/Tritium_illumination" class="mw-redirect" title="Tritium illumination">tritium</a>-based luminous material in the 1970s and finally by non-toxic, non-radioactive <a href="/wiki/Strontium_aluminate" title="Strontium aluminate">strontium aluminate</a>–based <a href="/wiki/Photoluminescent" class="mw-redirect" title="Photoluminescent">photoluminescent</a> material from the middle 1990s. </p><meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Radium_dial&action=edit&section=1" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Radium_Girls" title="Radium Girls">Radium Girls</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:171122-ingersoll-radiolite-ad.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/e/e8/171122-ingersoll-radiolite-ad.jpg/220px-171122-ingersoll-radiolite-ad.jpg" decoding="async" width="220" height="212" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/e/e8/171122-ingersoll-radiolite-ad.jpg/330px-171122-ingersoll-radiolite-ad.jpg 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/e/e8/171122-ingersoll-radiolite-ad.jpg/440px-171122-ingersoll-radiolite-ad.jpg 2x" data-file-width="1225" data-file-height="1179" /></a><figcaption>November 1917 ad for an Ingersoll "Radiolite" watch, one of the first watches mass marketed in the USA featuring a radium-illuminated dial.</figcaption></figure> <p>Radium was discovered by <a href="/wiki/Marie_Curie" title="Marie Curie">Marie</a> and <a href="/wiki/Pierre_Curie" title="Pierre Curie">Pierre Curie</a> in 1898<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> and was soon combined with paint to make <a href="/wiki/Luminescent_paint#radioluminescent_paint" class="mw-redirect" title="Luminescent paint">luminescent paint</a>, which was applied to clocks, airplane instruments, and the like, to be able to read them in the dark.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>In 1914, Dr. Sabin Arnold von Sochocky and Dr. George S. Willis founded the Radium Luminous Material Corporation. The company made luminescent paint. The company later changed its name to the <a href="/wiki/United_States_Radium_Corporation" title="United States Radium Corporation">United States Radium Corporation</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (May 2022)">citation needed</span></a></i>]</sup> The use of radium to provide luminescence for hands and indices on watches soon followed. </p><p>The <a href="/wiki/Ingersoll_Watch_Company" title="Ingersoll Watch Company">Ingersoll Watch</a> division of the <a href="/wiki/Waterbury_Clock_Company" class="mw-redirect" title="Waterbury Clock Company">Waterbury Clock Company</a>, a nationally-known maker of low-cost pocket and wristwatches, was a leading popularizer of the use of radium for watch hands and indices through the introduction of their "Radiolite" watches in 1916.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> The Radiolite series, made in various sizes and models, became a signature of the Connecticut-based company. </p><p>Radium dials were typically painted by young women, who used to 'point' their brushes by licking and shaping the bristles prior to painting the fine lines and numbers on the dials. This practice resulted in the ingestion of radium, which caused serious jaw-bone degeneration and malignancy and other dental diseases. The disease, <a href="/wiki/Radium_jaw" title="Radium jaw">radium-induced osteonecrosis</a>, was recognized as an <a href="/wiki/Occupational_disease" title="Occupational disease">occupational disease</a> in 1925 after a group of radium painters, known as the <a href="/wiki/Radium_Girls" title="Radium Girls">Radium Girls</a>, from the <a href="/wiki/United_States_Radium_Corporation" title="United States Radium Corporation">United States Radium Corporation</a> sued. By 1930, all dial painters stopped pointing their brushes by mouth. Stopping this practice drastically reduced the amount of radium ingested and therefore, the incidence of malignancy. </p><p>Luminous Processes employees interviewed by a journalist in 1978 stated they had been left ignorant of radium's dangers. They were told that eliminating lip-pointing had ended earlier problems. They worked in unvented rooms, they wore smocks that they laundered at home. <a href="/wiki/Geiger_counter" title="Geiger counter">Geiger counters</a> could pick up readings from pants returned from a dry cleaner and from clothes stored away in a cedar chest."<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Safety">Safety</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Radium_dial&action=edit&section=2" title="Edit section: Safety"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Elgin-WWII.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/d/d9/Elgin-WWII.jpg/220px-Elgin-WWII.jpg" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/d/d9/Elgin-WWII.jpg/330px-Elgin-WWII.jpg 1.5x, //upload.wikimedia.org/wikipedia/en/d/d9/Elgin-WWII.jpg 2x" data-file-width="397" data-file-height="397" /></a><figcaption>Wristwatch produced for the US Army during World War II showing characteristic sandy deterioration of radium–zinc sulfide painted hands and numbers. Such a watch should not be opened due to the danger of inhalation of airborne particles.</figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Radium_dial_radon_experiment.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/71/Radium_dial_radon_experiment.jpg/220px-Radium_dial_radon_experiment.jpg" decoding="async" width="220" height="299" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/71/Radium_dial_radon_experiment.jpg/330px-Radium_dial_radon_experiment.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/71/Radium_dial_radon_experiment.jpg/440px-Radium_dial_radon_experiment.jpg 2x" data-file-width="2603" data-file-height="3537" /></a><figcaption>Three radium dials and a radon detector are placed in a sealed plastic container. After 6 hours, the radon level was 446 pCi/L.</figcaption></figure> <p>According to the United States Environmental Protection Agency, "radioactive antiques [including watches] are usually not a health risk as long as they are intact and in good condition."<sup id="cite_ref-EPA_5-0" class="reference"><a href="#cite_note-EPA-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> However, radium is highly radioactive, emitting <a href="/wiki/Alpha_particles" class="mw-redirect" title="Alpha particles">alpha</a>, <a href="/wiki/Beta_particles" class="mw-redirect" title="Beta particles">beta</a>, and <a href="/wiki/Gamma_radiation" class="mw-redirect" title="Gamma radiation">gamma radiation</a> — the effects of which are particularly deleterious if inhaled or ingested since there is no shielding within the body.<sup id="cite_ref-EPA_5-1" class="reference"><a href="#cite_note-EPA-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> Indeed, the body treats radium as it does <a href="/wiki/Calcium" title="Calcium">calcium</a>, storing it in bone where it may cause bone degeneration and cancer.<sup id="cite_ref-EPA_5-2" class="reference"><a href="#cite_note-EPA-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Therefore, it is of the utmost importance that <i><b>watches with radium dials should not be taken apart</b></i><sup id="cite_ref-EPA_5-3" class="reference"><a href="#cite_note-EPA-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> without proper training, technique, and facilities. Radium paint can be ingested by inhaling flaking paint particles. The alpha particles emitted by the radium, which is taken up in bone, will kill off surrounding bone tissue, resulting in a condition loosely referred to as <a href="/wiki/Radium_jaw" title="Radium jaw">radium jaw</a>. Inhaled or ingested particles may deposit a high local dose with a risk of radiation-caused lung or gastrointestinal cancer. Penetrating gamma radiation produced by some dials also represents a significant health risk. </p><p>Although old radium dials generally no longer produce light, this is due to the breakdown of the <a href="/wiki/Crystal_structure" title="Crystal structure">crystal structure</a> of the luminous <a href="/wiki/Zinc_sulfide" title="Zinc sulfide">zinc sulfide</a> rather than the <a href="/wiki/Radioactive_decay" title="Radioactive decay">radioactive decay</a> of the radium. The radium isotope (<a href="/wiki/Radium-226" title="Radium-226"><sup>226</sup>Ra</a>) used has a <a href="/wiki/Half-life" title="Half-life">half-life</a> of about 1,600 years,<sup id="cite_ref-radiumepa_6-0" class="reference"><a href="#cite_note-radiumepa-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> so radium dials remain essentially just as radioactive as when originally painted 50 or 100 years ago, whether or not they remain luminous. </p><p>Radium dials held near the face have been shown to produce radiation doses in excess of 10 μSv / hour.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2022)">citation needed</span></a></i>]</sup> After about 20 minutes this delivers the equivalent of one whole day's worth of normal <a href="/wiki/Background_radiation" title="Background radiation">background radiation</a>.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (February 2022)">citation needed</span></a></i>]</sup> This rate probably only represents the dose rate from gamma emission, as the alpha emission will be stopped by the lacquer, or crystal, or case; hence, the dose rate following ingestion or inhalation of the dust could be much higher. </p><p>Chronic exposure to high levels of radium can result in an increased incidence of <a href="/wiki/Bone_cancer" class="mw-redirect" title="Bone cancer">bone</a>, <a href="/wiki/Liver_cancer" title="Liver cancer">liver</a>, or <a href="/wiki/Breast_cancer" title="Breast cancer">breast cancer</a>.<sup id="cite_ref-radiumepa_6-1" class="reference"><a href="#cite_note-radiumepa-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Decaying radium also produces the gas <a href="/wiki/Radon" title="Radon">radon</a>, recognized as the second leading cause of <a href="/wiki/Lung_cancer" title="Lung cancer">lung cancer</a> in the United States<sup id="cite_ref-radiumepa_6-2" class="reference"><a href="#cite_note-radiumepa-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> and the United Kingdom.<sup id="cite_ref-northampton_7-0" class="reference"><a href="#cite_note-northampton-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> A 2018 study by researchers from the <a href="/wiki/University_of_Northampton" title="University of Northampton">University of Northampton</a> found that a collection of 30 vintage <a href="/wiki/Military_watches" class="mw-redirect" title="Military watches">military watches</a> with radium dials kept in a small, unventilated room produced a radon concentration 134 times greater than the UK's recommended "safe" level.<sup id="cite_ref-northampton_7-1" class="reference"><a href="#cite_note-northampton-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p><p>Ingestion of radium has been linked to <a href="/wiki/Anemia" title="Anemia">anemia</a>, <a href="/wiki/Cataracts" class="mw-redirect" title="Cataracts">cataracts</a>, broken teeth, and reduced bone growth.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Regulation">Regulation</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Radium_dial&action=edit&section=3" title="Edit section: Regulation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:220101-BuffaloTimes-RadiumKingOfCures-ad.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/220101-BuffaloTimes-RadiumKingOfCures-ad.jpg/220px-220101-BuffaloTimes-RadiumKingOfCures-ad.jpg" decoding="async" width="220" height="178" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/220101-BuffaloTimes-RadiumKingOfCures-ad.jpg/330px-220101-BuffaloTimes-RadiumKingOfCures-ad.jpg 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/220101-BuffaloTimes-RadiumKingOfCures-ad.jpg/440px-220101-BuffaloTimes-RadiumKingOfCures-ad.jpg 2x" data-file-width="849" data-file-height="687" /></a><figcaption>Radium was initially touted as a positively salutary substance, as this January 1922 ad from the <i>Buffalo Times</i> illustrates.</figcaption></figure> <p>In the United States there does not seem to have ever been prohibitory legislation passed banning the use of radium in clocks and watches. It was only with the passage of the <a href="/wiki/Energy_Policy_Act_of_2005" title="Energy Policy Act of 2005">Energy Policy Act of 2005</a> that the <a href="/wiki/United_States_Nuclear_Regulatory_Commission" class="mw-redirect" title="United States Nuclear Regulatory Commission">United States Nuclear Regulatory Commission</a> (NRC) was given oversight of the use of radium.<sup id="cite_ref-NRC_9-0" class="reference"><a href="#cite_note-NRC-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> Prior to that date, "the federal government had a limited role, if any, in ensuring the safe use of radium," according to the NRC.<sup id="cite_ref-NRC_9-1" class="reference"><a href="#cite_note-NRC-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> The element was phased out of use by industry acting under its own volition as superior and safer luminous materials entered the marketplace. </p> <div class="mw-heading mw-heading2"><h2 id="Brands">Brands</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Radium_dial&action=edit&section=4" title="Edit section: Brands"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><i><a href="/wiki/Undark" title="Undark">Undark</a></i> produced by the <a href="/wiki/United_States_Radium_Corporation" title="United States Radium Corporation">United States Radium Corporation</a></li> <li><i>Luna</i> produced by the <a href="/wiki/Radium_Dial_Company" title="Radium Dial Company">Radium Dial Company</a></li> <li><i>Marvelite</i> produced by the Cold Light Manufacturing Company (a subsidiary of the Radium Company of Colorado)</li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Radium_dial&action=edit&section=5" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Phosphor#Radioluminescence" title="Phosphor">Radioactive phosphors</a></li> <li><a href="/wiki/Uranium_glass" title="Uranium glass">Uranium glass</a></li> <li><a href="/wiki/Super-LumiNova" title="Super-LumiNova">Super-LumiNova</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Footnotes">Footnotes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Radium_dial&action=edit&section=6" title="Edit section: Footnotes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width reflist-columns-2"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.radioactivity.eu.com/site/pages/Radium.htm">"Radioactivity : Radium"</a>. <i>www.radioactivity.eu.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2022-03-22</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.radioactivity.eu.com&rft.atitle=Radioactivity+%3A+Radium&rft_id=https%3A%2F%2Fwww.radioactivity.eu.com%2Fsite%2Fpages%2FRadium.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARadium+dial" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www3.epa.gov/radtown/antiques.html">"RadTown"</a>. 21 June 2017.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=RadTown&rft.date=2017-06-21&rft_id=https%3A%2F%2Fwww3.epa.gov%2Fradtown%2Fantiques.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARadium+dial" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.newspapers.com/clip/103333171/the-new-waterbury-radiolite-watch/">"Which of These Two Are You?"</a> (ad) <i>New York Tribune,</i> May 24, 1916, p. 6.</span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text">Claudia Clark, <i>The Radium Girls.</i> (<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-8078-4640-7" title="Special:BookSources/978-0-8078-4640-7">978-0-8078-4640-7</a>)</span> </li> <li id="cite_note-EPA-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-EPA_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-EPA_5-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-EPA_5-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-EPA_5-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.epa.gov/radtown/radioactivity-antiques">"Radioactivity in Antiques,"</a> United States Environmental Protection Agency, www.epa.gov, accessed June 6, 2022.</span> </li> <li id="cite_note-radiumepa-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-radiumepa_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-radiumepa_6-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-radiumepa_6-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.epa.gov/radiation/radionuclide-basics-radium">"Radionuclide Basics: Radium,"</a> United States Environmental Protection Agency, www.epa.gov, accessed June 6, 2022.</span> </li> <li id="cite_note-northampton-7"><span class="mw-cite-backlink">^ <a href="#cite_ref-northampton_7-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-northampton_7-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20210126012657/https://www.northampton.ac.uk/news/wwii-military-watches-potentially-pose-serious-cancer-risk/">"WWII Military Watches 'Potentially Pose Serious Cancer Risk,'</a> Faculty of Arts, Science, and Technology, University of Northampton, www.northampton.ac.uk/ June 14, 2018.</span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.mass.gov/service-details/health-effects-of-radium-radiation-exposure">"Health Effects of Radium Radiation Exposure,"</a> Massachusetts Department of Public Health, mass.gov/, accessed June 7, 2022.</span> </li> <li id="cite_note-NRC-9"><span class="mw-cite-backlink">^ <a href="#cite_ref-NRC_9-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-NRC_9-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20210619061316/https://www.nrc.gov/materials/radium.html">"Radium,"</a> United States Nuclear Regulatory Commission, www.nrc.gov/, June 19, 2021.</span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Radium_dial&action=edit&section=7" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Jane Brickman, "Radium Girls: Women and Industrial Health Reform, 1910–1935," <i>Journal of Public Health Policy,</i> v. 21, no. 2 (June 2000), pp. 245–247.</li> <li>Kate Moore, <i>The Radium Girls: The Dark Story of America's Shining Women.</i> Naperville, IL: Sourcebooks, 2018.</li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Radium_dial&action=edit&section=8" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Joe Baron, <a rel="nofollow" class="external text" href="https://www.watchprozine.com/horological-meandering/watches-and-radiation-risk/7232898/17/">"Watches and Radiation Risk,"</a> Watchprozine.com, Nov. 9, 2015.</li> <li>Kathleen McGivney, <a rel="nofollow" class="external text" href="https://www.youtube.com/watch?v=3Kew04Qgc1I">"How I Learned to Stop Worrying and Love Radium Dials,"</a> [Video] <a href="/wiki/Horological_Society_of_New_York" title="Horological Society of New York">Horological Society of New York</a> via YouTube, Nov. 7, 2017. <small>—Talk starts at 6:08.</small></li> <li>Precision Watches, <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220606072446/https://precisionwatches.com/lume-in-watches/">"Lume 101: Watch Luminescence Explained,"</a> Precisionwatches.com, captured June 6, 2022.</li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Radium_dial&oldid=1241816198">https://en.wikipedia.org/w/index.php?title=Radium_dial&oldid=1241816198</a>"</div></div> 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