编辑“︁氯”︁（章节）

==危险性==
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氯是一种有毒的气体，会攻击呼吸系统、眼睛和皮肤。<ref>{{Cite web|url=http://www.bt.cdc.gov/agent/chlorine/basics/facts.asp |title=Facts About Chlorine |website=www.bt.cdc.gov |access-date=2016-04-12 |url-status= |archive-url=https://web.archive.org/web/20160423193302/http://www.bt.cdc.gov/agent/chlorine/basics/facts.asp |archive-date=2016-04-23 }}</ref>它比空气密度大，所以它往往会积聚在通风不良的空间底部。氯是一种强氧化剂，可能与易燃材料发生反应。<ref name="msds-cl">{{cite web|url=http://www.westlake.com/datasheets/MSDS_Chlorine.pdf |archive-url=https://web.archive.org/web/20070926183417/http://www.westlake.com/datasheets/MSDS_Chlorine.pdf |archive-date= 2007-09-26 |title=Chlorine MSDS|date=1997-10-23}}</ref><ref>{{cite web|url=http://cameochemicals.noaa.gov/chemical/2862|title=Chlorine|author=NOAA Office of Response and Restoration, US GOV|work=noaa.gov|access-date=2015-08-25|url-status=live|archive-url=https://web.archive.org/web/20151015212302/http://cameochemicals.noaa.gov/chemical/2862|archive-date=2015-10-15}}</ref>

通过测量仪器可以检测到0.2 ppm的氯气，在3 ppm时可以嗅到。在30 ppm 的氯气下会造成咳嗽和呕吐，在60&nbsp;ppm下会损害肺部。1000&nbsp;ppm（0.1%）的氯气在几次呼吸中就可以造成生命危险。{{sfn|Greenwood|Earnshaw|1997|pp=792–793}}氯气的{{le|立刻对生命和健康造成危险值|IDLH}}为 10 ppm。<ref name=":0">{{PGCH|0115}}</ref>呼吸低浓度氯气会加重呼吸系统的负担，暴露在氯气中会刺激眼睛。<ref name=tox>{{cite journal|journal = Environmental Research|volume = 85|issue = 2|date = 2001 |doi = 10.1006/enrs.2000.4110 |title = The Toxicology of Chlorine|author = Winder, Chris|pages = 105–14|pmid = 11161660|bibcode = 2001ER.....85..105W }}</ref>氯的危害来自于其强氧化性。当氯气的浓度在 30&nbsp;ppm以上时，它会和水或体液反应，形成[[盐酸]] (HCl) 和[[次氯酸]] (HClO)。

当用于水消毒时，氯与水的反应不是人类健康的主要问题。 水中存在的其他物质可能会产生{{le|消毒副产物|Disinfection_by-product}}，这些副产物会对人类健康产生负面影响。<ref>{{cite web|url=http://news.aces.illinois.edu/news/whats-your-water-disinfectants-create-toxic-products|title=What's in your Water?: Disinfectants Create Toxic By-products|date=2009-03-31|work=ACES News|publisher=College of Agricultural, Consumer and Environmental Sciences – University of Illinois at Urbana-Champaign|access-date=2009-03-31|url-status=live|archive-url=https://web.archive.org/web/20140903101530/http://news.aces.illinois.edu/news/whats-your-water-disinfectants-create-toxic-products|archive-date=2014-09-03}}</ref><ref>{{cite journal |doi=10.1016/j.mrrev.2007.09.001 |title=Occurrence, genotoxicity, and carcinogenicity of regulated and emerging disinfection by-products in drinking water: A review and roadmap for research |date=2007 |last1=Richardson |first1=Susan D. |last2=Plewa |first2=Michael J. |last3=Wagner |first3=Elizabeth D. |last4=Schoeny |first4=Rita |last5=DeMarini |first5=David M. |journal=Mutation Research/Reviews in Mutation Research |volume=636 |pages=178–242 |pmid=17980649 |issue=1–3}}</ref>

在美国，[[美国职业安全与健康管理局]] (OSHA) 把氯气的[[允许接触限值]]定在 1 ppm，或是 3&nbsp;mg/m<sup>3</sup>。[[美国国家职业安全卫生研究所]]则把{{le|推荐接触限值|recommended exposure limit}}定在 0.5 ppm （暴露超过15 分钟）。<ref name=":0" />

在家里，当次氯酸盐漂白溶液与某些酸性排水管清洁剂接触产生氯气时，就会发生事故。<ref>{{Cite web|url=https://www.forbes.com/sites/alexberezow/2013/11/04/why-you-should-never-mix-different-drain-cleaners/#1d08c8fc32c8|title=Why You Should Never Mix Different Drain Cleaners|last=Berezow|first=Alex|website=Forbes|access-date=2016-04-12|url-status=live|archive-url=https://web.archive.org/web/20160425184357/http://www.forbes.com/sites/alexberezow/2013/11/04/why-you-should-never-mix-different-drain-cleaners/#1d08c8fc32c8|archive-date=2016-04-25}}</ref>次氯酸盐漂白剂（一种[[洗衣]]添加剂）和[[氨]]（另一种洗衣添加剂）反应会产生{{le|氯胺类|chloramines}}，另一类有毒化学品。<ref>{{Cite web|url=http://www.doh.wa.gov/YouandYourFamily/HealthyHome/Contaminants/BleachMixingDangers|title=Bleach Mixing Dangers : Washington State Dept. of Health|website=www.doh.wa.gov|access-date=2016-04-12|url-status=live|archive-url=https://web.archive.org/web/20160414074554/http://www.doh.wa.gov/YouandYourFamily/HealthyHome/Contaminants/BleachMixingDangers|archive-date=2016-04-14}}</ref>

=== 氯导致的材料开裂 ===
氯广泛用于净化水，特别是饮用水和游泳池用水。 由于氯引起的[[不锈钢]]吊杆{{le|应力腐蚀开裂|Stress_corrosion_cracking}}，游泳池天花板发生了几次灾难性的倒塌。<ref>{{Cite book|url=https://books.google.com/books?id=cEmq232h1zcC&pg=PA148|page=148|title=Corrosion of steel in concrete: prevention, diagnosis, repair|author=Bertolini, Luca|author2=Elsener, Bernhard|author3=Pedeferri, Pietro|author4=Polder, Rob B.|publisher=Wiley-VCH|date=2004|isbn=978-3-527-30800-2|access-date=2021-06-13|archive-date=2020-06-14|archive-url=https://web.archive.org/web/20200614085047/https://books.google.com/books?id=cEmq232h1zcC&pg=PA148%2F|dead-url=no}}</ref>一些[[聚合物]]也对攻击敏感，包括[[聚甲醛]]和{{le|聚丁烯|polybutene}}。这两种材料都用于冷热水家用管道，而{{le|应力腐蚀开裂|Stress_corrosion_cracking}}在 1980 年代和 1990 年代在美国引起了广泛的故障。<ref>{{cite book|author=Lewis, P.R.|title=Polymer Product Failure|url=https://books.google.com/books?id=SFm8rKotSaUC&pg=PA19|access-date=2011-04-30|date=2000-01-01|publisher=iSmithers Rapra Publishing|isbn=978-1-85957-192-7|pages=19–|url-status=live|archive-url=https://web.archive.org/web/20130510041524/http://books.google.com/books?id=SFm8rKotSaUC&pg=PA19|archive-date=2013-05-10}}</ref>

===氯-铁火 ===
[[铁]]会和氯在高温下反应。这是一个强放热反应，会产生氯-铁火。<ref name=bayerdatasheet2008>{{cite web|url=https://tecci.bayer.de/io-tra-pro/emea/de/docId-2857612/Chlorine.pdf |title=Chlorine: Product Datasheet |publisher=Bayer MaterialScience AG |date=2008-04-21 |access-date=2013-12-17 |url-status=dead |archive-url=https://web.archive.org/web/20120915114003/https://tecci.bayer.de/io-tra-pro/emea/de/docId-2857612/Chlorine.pdf |archive-date=2012-09-15 }}</ref><ref name="sanders2004">{{Cite book | isbn = 978-0-7506-7749-3 | title = Chemical Process Safety: Learning from Case Histories, 3rd Revised edition | last1 = Sanders | first1 = Roy E. | year = 2004 | publisher = Elsevier Science & Technology | location = Oxford | page = 92 }}</ref>氯-铁火在化工厂中是一种风险，其中大部分输送氯气的管道是由钢制成的。<ref name=bayerdatasheet2008/><ref name=sanders2004/>