N95 Respirator Mask Requirements for Aerosol-Generating Procedures on TB Patients

Introduction to N95 Respirator Masks

The Centers for Disease Control and Prevention (CDC) recommends that healthcare workers wear N95 respirator masks (or equivalent NIOSH-certified respirators with ≥95% filtration efficiency) when performing aerosol-generating procedures on patients with suspected tuberculosis 1, 2, 3, 4.

Surgical masks do not provide adequate protection for healthcare workers during aerosol-generating procedures because they lack a tight facial seal and cannot effectively filter droplet nuclei in the 1-5 micron size range that contains M. tuberculosis 1, 5.
Face shields alone offer no respiratory protection against airborne droplet nuclei 6.
Gloves alone provide no protection against inhalation of infectious particles 1.

The CDC guidelines specify that respirators used for TB protection must have a filter efficiency ≥95% for particles 1 micron in size at flow rates up to 50 L/minute 1, 4.
The CDC guidelines also specify that respirators used for TB protection must have a face-seal leakage ≤10% when properly fit-tested 1.
Available in at least three sizes to accommodate different facial characteristics 1.
Must be qualitatively or quantitatively fit-tested for each healthcare worker 1.

Healthcare workers must wear N95 respirators when present during endotracheal intubation and suctioning on suspected TB patients 2, 3.
Healthcare workers must wear N95 respirators when present during diagnostic sputum induction on suspected TB patients 2, 3.
Healthcare workers must wear N95 respirators when present during bronchoscopy on suspected TB patients 2, 3.
Healthcare workers must wear N95 respirators when present during aerosol treatments (e.g., pentamidine therapy) on suspected TB patients 2, 3.
Healthcare workers must wear N95 respirators when present during irrigation of tuberculous abscesses on suspected TB patients 2, 3.

Complete PPE should include a fitted, NIOSH-certified N95 mask (or PAPR if available for long procedures) 6.
Complete PPE should include eye protection: goggles covering sides of eyes or full-face shields 6.
Complete PPE should include a disposable AAMI level-III surgical gown or coveralls 6.
Complete PPE should include double high-cuffed surgical gloves 6.
Hand hygiene should be performed before and after donning/doffing PPE 6.

Each healthcare worker must be fit-tested for each different type of N95 respirator model used 7.
Workers should perform user seal checks each time they don the respirator 1.
Patients with suspected TB should wear surgical masks (not N95 respirators) when outside isolation rooms to prevent expulsion of droplet nuclei 2, 3, 8.
Patients should never wear respirators with exhalation valves, as these do not prevent transmission 3, 8.
Healthcare workers need N95 respirators to filter inhaled air; patients need surgical masks to contain exhaled droplet nuclei 2, 3.

Healthcare facilities using respiratory protection for TB prevention are required by OSHA to develop, implement, and maintain a comprehensive respiratory protection program that includes all healthcare workers who use respirators 3.