The Determination of the Inward Leakage through the Skin–Facepiece Interface of the Protective Half-Mask

Abstract

The present article describes the measurements of flow rates of the inward air leakage through the skin–facepiece interface of a protective half-mask with replaceable filters. The measurements were carried out while applying an indirect method in which the pressure drops in a compressed air container were measured, and subsequently, the total flow rate of the leak was calculated. This methodology facilitated measuring extremely low air flow rates at the atmospheric pressure of 3.2 × 10−6 m3·s−1. A numerical analysis of the inward air leakage through the gaps between the face and the facepiece of the mask was carried out with the aim of identifying the cross-sectional area of the leak. With the tested mask, which was made of Santoprene 8281-45MED, the leakage measured during inhalation was 0.21%, which corresponded to the cross-sectional area of only 0.14 mm2.

Development and Testing of Copper Filters for Efficient Application in Half-Face Masks

“…The controlling software of the prototype device also contained an additionally programmed section of the controlling code which facilitated using the obtained values of physical parameters to calculate the coefficient of resistance and filter permeability. Figure 1a shows a functional prototype device intended for the identification of pressure drops in filters with automatic measurement of permeability and coefficient of resistance [18].…”

Measurements of Operating Parameters of a Metal Hydride Compressor with a Heat Pump

“…One of the possible means of hydrogen compression is the use of reversible hydrogen storage in metal alloys, while applying a method based on thermal changes [13]. This technology was also discussed in paper [14], which pointed out a continuous growth of the R&D activities in the development of the metal hydride hydrogen compression technology.…”