Q: We are an ambulatory surgery center. Does every employee need an N95 respirator for protection from H1N1; must they all be fit tested and who does the fit testing?
A: OSHA emphasizes a hierarchy of controls that includes eliminating the source of infection, engineering controls, administrative controls, and lastly, personal protective equipment, the category that concerns the use of N95 respirators. (Click here for specific examples of controls applicable to healthcare settings.) 
Working through the hierarchy should reduce the number of staff members who are required to wear an N95.
Whenever you require staff to wear respirators, including an N95, OSHA says you must have a written respiratory protection plan in place. According to the Respiratory Protection standard, 1910.134,  the elements of such a plan must address: a plan administrator; respirator selection; medical evaluations; fit testing; user seal checks; maintenance and care of respirators; cleaning and disinfection; storage of respirators; training and information. (Click here for more details on elements of the plan.) 
Fit testing, which is part of the respiratory protection plan, may be performed by you, the employer, if you are qualified. OSHA considers a person qualified to do fit testing if he/she is familiar with one of the two acceptable fit test methods as well as the limitations of the models of respirators being tested. See “Ask the expert: Trainer qualifications for fit testing,” for details.