The U.S. Occupational Safety & Health Administration will begin enforcing a final rule limiting occupational exposure to beryllium in general industry, construction, and shipyards on May 11, two months later than planned. Airborne beryllium damages workers’ lungs through exposure from a host of activities: foundry and smelting operations, fabricating, machining, grinding beryllium metal and alloys, ceramics manufacturing, and dental lab work. Beryllium exposure is also a concern for people handling fly ash residue from coal-burning power plants and in the construction and shipyard industries. The final rule replaces a 40-year-old exposure limit that was outdated and did not adequately protect worker health, OSHA says. OSHA formally began a rule-making process in 2002 and proposed a rule in 2015. Once in place, the rule will toughen exposure limits to one-tenth of the current level. OSHA has estimated the rule will save the lives of 94 workers annually. The delay was necessary to provide more time for compliance, OSHA says.