Mask Fit Testing of Respiratory Protective Equipment

Mask Fit Testing

Mask fit testing evaluates the quality of the seal between the mask and the user’s face. This test is mandatory for all snug-fitting masks, which include:

• Disposable half-face masks
• Reusable half-face masks
• Reusable full-face masks
• Snug-fitting powered air purifying respirators (PAPR)

Two primary methods of fit testing align with AS/NZS1715:2009 standards regarding the selection, use, and maintenance of respiratory protective gear: Qualitative and Quantitative. For our purposes, we will conduct Quantitative mask fit testing.

Mask Fit Testing: Quantitative Method

This method employs advanced particle counting tools to gauge air leakage into the mask. Essentially, it assesses particle concentration outside the mask and contrasts this to the particle concentration inside the face piece. The resulting ratio produces a fit factor, which indicates if a proper fit has been achieved. This testing approach is suitable for half-face masks, full-face masks, and PAPRs.

For both the qualitative and quantitative testing techniques, participants are guided through simple actions such as turning their head side to side, tilting it up and down, and speaking. These activities mimic common workplace movements to ensure the mask remains secure during everyday tasks.

Mask Fit Testing: Quantitative vs. Qualitative

Quantitative mask fit testing results offer a more objective perspective than qualitative ones, primarily because qualitative assessments rely heavily on the participant’s sense of smell for a pass/fail judgment. This reliance can potentially lead to inaccuracies, allowing for a false pass in the qualitative fit test and possibly compromising worker safety.

According to AS 1715:2009, mask fit testing needs to be executed by someone competent, whether it’s an in-house individual, manufacturer, supplier, or consultant. Fit testing should be conducted:

• Annually;
• Prior to wearing a snug-fitting respirator for the first instance;
• Each time a different brand or design of the respirator is provided;
• Anytime there’s a significant alteration in the wearer’s facial appearance or features that might affect the mask’s seal, such as notable weight fluctuations.

It’s crucial to highlight that facial hair interfering with the seal area of a snug-fitting mask can compromise its effectiveness. For males, fit testing should be done when they are either clean-shaven or have ensured there’s no hair obstructing the mask’s fitting surfaces against the face.