Abstract
The purpose is to substantiate theoretically the design of elastomeric half mask and canister of respirator of long-term protection. To develop the models for theoretical calculations of protective properties of dust masks the theory of non-stationary filtration and hydro aerodynamics was applied. To develop the digital model of a head the downhill simplex method was applied reflecting separate face features considering sex or age; to determine the halfmask surface the free energy equation for bowed plate being described by two-dimension spline surface was used with its unknown coefficients determined by method of proportional parts based on three-dimension coordinates of anthropometric face features. The main anthropometric face features influencing halfmasks design were determined to develop polygonous 3D model of head. According to its determined basic coordinates the surface of halfmask was determined using method of interpolation. Considering the mathematical model describing the movement of dust flows near a halfmask and in canister the dependences of distribution of air flow speed in a canister of variable geometry were set and kinematic parameters of dust-laden airflow according to a canister volume were determined. Reasonable geometric parameters of canister were determined; transient modulation from filter to inlet valve hole is performed as a contractor.
Highlights
Respiratory system protection from aerosols remains quite an urgent issue
individual respiratory protective devices (IRPD) designing is mainly performed by means of heuristic approaches mostly based on the developers’ ultimate beliefs, the experience of previous projects, databases on known similar products
The quality of IRPD design is determined by the performance characteristics of components meeting the requirements stated in regulatory documents
Summary
Adequate use of high-quality one-use or reusable masks plays an important role in its solution The efficiency of their use is directly dependent on physical and chemical properties of filter or sorption and filter materials and halfmask design to provide reliable isolation of employee’s respiratory system from hazardous substances. IRPD designing is mainly performed by means of heuristic approaches mostly based on the developers’ ultimate beliefs, the experience of previous projects, databases on known similar products It can be described using the framework representing the main project stages (Fig. 1): Fig. 1. According to the components described five categories of employees’ face types are distinguished: small, short – wide, medium, long and tall, large (Fig. 2) They become the base for determining the requirements to the frame of IRPD
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
