OSHA proposes a formula for pandemic stockpiles

480 N95s or one elastomeric needed per HCW

For the first time, a newly proposed guidance puts a number and a cost to the respirators needed to protect health care workers during an influenza pandemic: 480 respirators at a cost of about $240 to protect a single employee, or a single reusable elastomeric respirator with three filters at a cost of $40 per employee.

The U.S. Occupational Safety and Health Administration issued the proposed guidance to help employers determine how many respirators and facemasks to stockpile for pandemic preparedness (www.osha.gov). It requested comments on the guidance through July 8.

OSHA is encouraging employers to stockpile respirators because "manufacturing capacity at the time of an outbreak would not meet the expected demand for respiratory protection devices during the pandemic," the agency said. "It is also important to note that respirators and facemasks are just one element of a multilayered approach to pandemic preparedness. There are many other protective measures that can and should be elements of a comprehensive pandemic preparedness plan."

"When you put all this together, we believe there will be substantial ability to protect critical work forces and the population in general," says Ben Schwartz, MD, senior science adviser with the National Vaccine Program Office at the U.S. Department of Health and Human Services, who helped OSHA draft the respirator guidance.

The Cost of Stockpiling These cost estimates were developed by OSHA for a single employee at high risk of exposure: • Option 1 — Using disposable N95 respirators: 480 N95s @ $0.50/respirator = $240 per employee protected • Option 2 — Using reusable elastomeric respirators:

— 1 respirator @ $25 + 3 sets of filters @ $5 set = $40 per employee protected • Option 3 — Using 1 PAPRs shared by 4 employees on shift work:

— 1 PAPR @ $800 + 1 spare battery @$160 + 3 extra hoods @ $90 each + 3 sets of filters @ $30 set = $1,320 / 4 employees = $330 per employee protected (Note: Hooded PAPRs do not need to be fit-tested, which can result in other programmatic cost savings.)

Until now, hospitals and health systems have had to make their own assumptions and estimates to determine how many respirators to stockpile, says Lewis J. Radonovich, MD, director of Biosecurity Programs for the Office of Program Development at the North Florida/South Georgia Veterans Health System in Gainesville, FL.

"I think it's very valuable for the individual health care center or system to have this type of guidance available to them," says Radonovich, who has been involved in research on respiratory protection and pandemic preparedness. "Without this, we're all left to our own devices to make these decisions."

Hospitals are expected to adapt the guidance to their own particular circumstances. For example, in its proposed guidance, OSHA assumes that a third of hospital employees will be at high risk due to direct patient contact. The actual number, however, will vary based on the nature of the pandemic and personnel decisions.

If a disproportionate number of the pandemic influenza patients are children, then pediatric hospitals may be especially hard-hit and a higher proportion of their employees may be at risk. Conversely, hospitals may reduce the number of employees at risk by cohorting patients and limiting the number of nonclinical personnel who come onto the floor, says Schwartz.

The proposed guidance also estimates that each health care worker will use four disposable N95 respirators per shift. Employees would wear the respirators continuously and dispose of them after each of two breaks, at lunch and at the end of the day, he reports.

It isn't prudent to expect health care workers to reuse the respirator during the day, Schwartz says. "After several hours (of continuous use), it may become saturated with secretions and make the workers breathing a little more difficulty," he says, adding, "There is some risk of contamination by doffing and donning the contaminated respirator."

Hospitals also shouldn't count on extending the use of N95 respirators by asking employees to wear a surgical mask over the respirator to protect it from contamination, Schwartz notes.

"We have to be equally concerned about a shortage of face masks. Given the [OSHA] recommendations for use of face masks not only in health care but in other sectors as well, the estimated requirements [for face masks during a pandemic] are in the tens of billions," Schwartz says.

OSHA recommends face masks for employees who have "high-frequency, close contact (within 6 feet) of the general population." That would include store clerks, bank tellers, waiters, and numerous other service workers.

A pandemic can range from mild to severe, but in its proposed guidance, OSHA assumes that "community mitigation," such as closing schools and cancelling public gatherings, would reduce illness to about 15% of the population. The guidance is based on a pattern of two waves striking a community, each lasting 12 weeks. With a five-day workweek, that would equal 120 days of protection needed for employees.

Before deciding how many respirators to stockpile, hospitals should consider the types of respirators that would best suit their needs. Based on the cost comparison, elastomeric respirators would be the cheapest alternative.

VISN 8, the Veterans Health Administration health care network that encompasses Florida, southern Georgia, Puerto Rico, and the U.S. Virgin Islands, has purchased some elastomeric respirators in addition to N95s, says Radonovich.

Reusable respirators offer a clear advantage during a pandemic, he says. "We anticipate, based on warnings, that the manufacturers won't be able to produce enough disposable N95s during a pandemic to meet the demand. We needed another option," he says.

Yet elastomeric respirators pose issues as well. They must be fit-tested, just as N95s are. The facepiece may make it harder to communicate with patients. And they aren't comfortable to wear for long periods of time, says William Buchta, MD, MPH, medical director of the Employee Occupational Health Service at the Mayo Clinic in Rochester, MN.

Mayo has purchased 200,000 N95 respirators and 300,000 face masks for a pandemic stockpile. "We want to be able to last for a 2½-month period," he says. Mayo also has powered air-purifying respirators (PAPRs), which do not require fit-testing and, in some cases are recommended for high-risk procedures such as bronchoscopy.

The Marshfield (WI) Clinic has a warehouse full of N95 respirators, gloves, and gowns for a potential pandemic. Elastomerics sound like a good idea but have some drawbacks, says Bruce Cunha, RN, MS, COHN-S, manager of employee health and safety. "People just do not understand how uncomfortable it is to wear a [half-face] respirator for any length of time," he says. "You have a rubbery substance against your skin and you're breathing 98.6° air. The inside of those things get very warm, very quickly."

The reusables also need proper handling and cleaning. "You're going to have to train employees how to clean them properly, or you're going to have to have someone who cleans them on a daily basis," he says.

Schwartz urges health care employers at least to consider the elastomeric respirators — perhaps by trialing them at the hospital. The key is to have respirators that will be available in an emergency situation — and reusable respirators have an obvious advantage.

"While elastomerics may not be a solution for routine health care, I think it's important for planners to realize the primacy for maintaining services during an emergency," he says.

(Editor's note: For more information, go to www.osha.gov. Comments on the OSHA guidance can be made through July 8.)