In a slight change of course, two federal agencies have issued official guidance regarding the use of respirators by cleanup workers in the Gulf.

According to the National Institute for Occupational Safety and Health and the Occupational Safety and Health Administration, workers near the source of the spill will be provided respirators and should use them when: 1) “air monitoring indicates elevated level of contaminants,” 2) “when professional judgment determines there is potential exposure,” or 3) “when workers are reporting health effects.”

Here’s the language of their new guidance:

For workers involved in source control activities, respirators should be used in those situations where potentially excessive exposure is reasonably anticipated or where indicated by exposure assessment or where symptoms/health effects are being reported.

It's the first time these agencies have issued any formal guidance on when Gulf cleanup workers should wear respirators; in the past, both the government and BP have said respirators were not needed. But as industrial hygienist and former OSHA inspector Eileen Senn noted, “It remains to be seen if the NIOSH/OSHA recommendations will translate into more Gulf workers receiving respirators.” Senn pointed out that the guidance does not define what constitutes “excessive exposure,” even though OSHA and NIOSH have different chemical exposure limits. (As we’ve noted, OSHA chief David Michaels has called his agency’s limits “outrageously out of date.”)

When I asked NIOSH about the new respirator recommendations, Chief of Staff Frank Hearl told me the decision was made in order to “ramp up the degree of protection,” though he said enforcement was out of his agency’s jurisdiction.

“Coming from the government, jointly from NIOSH and OSHA, that’s a pretty strong statement of advice,” Hearl said.

I’ve also called OSHA, but have not yet heard back.