Editing Hafnium (section)

==Precautions==
Care needs to be taken when [[machining]] hafnium because it is [[pyrophoric]]—fine particles can spontaneously combust when exposed to air. Compounds that contain this metal are rarely encountered by most people. The pure metal is not considered toxic, but hafnium compounds should be handled as if they were toxic because the ionic forms of metals are normally at greatest risk for toxicity, and limited animal testing has been done for hafnium compounds.<ref>{{cite web|url = https://www.osha.gov/SLTC/healthguidelines/hafnium/index.html|title = Occupational Safety & Health Administration: Hafnium|publisher = U.S. Department of Labor|access-date = 2008-09-10|archive-url = https://web.archive.org/web/20080313003040/https://www.osha.gov/SLTC/healthguidelines/hafnium/index.html|archive-date = 2008-03-13}}</ref>

People can be exposed to hafnium in the workplace by breathing, swallowing, skin, and eye contact. The [[Occupational Safety and Health Administration]] (OSHA) has set the legal limit ([[permissible exposure limit]]) for exposure to hafnium and hafnium compounds in the workplace as TWA 0.5&nbsp;mg/m<sup>3</sup> over an 8-hour workday. The [[National Institute for Occupational Safety and Health]] (NIOSH) has set the same [[recommended exposure limit]] (REL). At levels of 50&nbsp;mg/m<sup>3</sup>, hafnium is [[IDLH|immediately dangerous to life and health]].<ref>{{Cite web|title = CDC – NIOSH Pocket Guide to Chemical Hazards – Hafnium|url = https://www.cdc.gov/niosh/npg/npgd0309.html|website = www.cdc.gov|access-date = 2015-11-03}}</ref>