Development of an algorithm for effective design of respirator half-masks and encapsulated particle filters.

Social and economic situations in the modern world require new approaches to the development of respiratory protective equipment. This study aimed to improve the three-dimensional modeling process for respirator half-masks and encapsulated particle filters. Basic provisions of the theory of non-stationary filtration and hydroaerodynamics, the Nelder-Mead method and the linear interpolation equation were used. The peculiarity of the algorithm is the adjustment stage of the design process aimed at checking efficiency of the half-mask. The surface of the half-mask was constructed according to the coordinates of a three-dimensional model of a worker's head. For the first time, the regularities of an algorithm for designing the half-mask surface of dust respirators were defined based on the data for three-dimensional coordinates of key points of anthropometric parameters of workers' faces. The pressure difference on the encapsulated particle filters of dust respirators is determined by the particle filter's resistance coefficient and air flow through them, and the diameter ratio of their outlets and inlets. The developed algorithm provides product verification at the design stage using criteria evaluating parameters of a polygonal model of the head, preliminary calculation of the protection factor and checking the tightness of the prototype.