A New Miniature Respirable Sampler for In-mask Sampling: Part 2-Tests Performed Inside the Mask

Area of Science:

• Occupational Health and Safety
• Industrial Hygiene
• Respiratory Protection Technology

Background:

• The first paper detailed the design and particle performance of a miniature, low-weight respirable sampler for respirator use.
• This study evaluates the sampler's comparability with established inward leakage measurement techniques and assesses its safety during use.

Purpose of the Study:

• To compare the performance of a miniature respirable sampler with traditional inward leakage measurement methods.
• To assess the safety and impact of the miniature sampler on the protective performance of filtering facepiece (FFP) and half-mask respirators.

Main Methods:

• Simultaneous mass measurements of sodium chloride aerosol using the miniature sampler and sodium flame photometry within an inward leakage chamber.
• Comparative testing with a breathing dummy head wearing four different respirator types fitted with the sampler.
• Human volunteer trials with three FFP models, with and without the miniature sampler, to evaluate protection levels.

Main Results:

• Excellent correlation (R² = 0.99) was observed between the miniature sampler and sodium flame photometry.
• No statistically significant difference (P = 0.3) in protection was found when volunteers wore FFP respirators with or without the miniature sampler.
• All tested masks performed within their designated protection classes, irrespective of sampler presence.

Conclusions:

• The miniature sampler is comparable to traditional methods for measuring respirable aerosols.
• The miniature sampler does not significantly compromise the protective efficacy of FFP and half-mask respirators.
• This device offers a viable option for in-mask measurements of respirable dust, particularly in low concentration environments.