17.2.4 Personal protective interventions
Personal protective equipment helps to prevent the individual healthworker or other TB-free individuals from getting infected. Key items for personal protection against TB are respirators and surgical masks (sometimes called procedure masks) and there are important differences between them (see Figures 17.3 and 17.4).
There are different respirators and the most commonly used type in the prevention of TB is the N95 class of respirator (also recommended by the WHO); examples of this type of respirator are shown in Figure 17.3. Respirators have very small pores (too small to see with the naked eye) that allow the wearer to breathe but prevent infectious agents from passing through (they are too big to pass through the pores). Importantly, these respirators form a tight seal around their entire edge so that the air you breathe has to pass through the respirator. Wearing these devices substantially reduces the risk of acquiring a TB infection. Health workers should use respirators when providing care to infectious TB patients or suspects, particularly those individuals who you suspect of having a drug-resistant form of the disease.
It is important that you know how to fit a N95 respirator, ensuring that you have a good seal between the mask and your skin.
Surgical masks prevent the spread of micro-organisms from the wearer (the surgeon, healthworker or TB patient, etc.) to others by capturing the large wet particles found in the wearer’s breath near the nose and mouth, and also limiting the distance aerosols are expelled when coughing, sneezing and talking. Surgical masks do not provide adequate protection to the wearer from inhaling infectious droplet particles produced by TB patients (Figure 17.4). This is because masks fit loosely over the mouth and nose, which means they allow free entry of aerosols that may be contaminated with M. tuberculosis.
Surgical masks do not adequately protect wearers from inhalation of air contaminated with M. tuberculosis and should not be used for that purpose.
17.2.3 Environmental controls
17.3 Infection control where people gather, at community and household level