№62-09

Estimation of adjustment density elastomeric half-mask to the face

Yu. Cheberiachko¹, O. Boyko¹, I. Knish¹, A.Yurchenko¹, O. Shustov¹

¹Dnipro University of Technology, Dnipro, Ukraine

Coll.res.pap.nat.min.univ. 2020, 62:100-111

https://doi.org/10.33271/crpnmu/62.100

Full text (PDF)

ABSTRACT

Purpose. Development of a method for estimating the tightness of the elastomeric half-mask to the face of workers according to the thermographic image of the obturator.

Methodology. The estimation is based on the application of a static approach to the estimation of thermographic images of the half-mask obturation band using built-in functions in the MATLAB mathematical environment using the integrative algorithm of nearest points - the ICP method.

Findings. A method for estimating the tightness of the half-mask to the face by thermographic imaging of the obturator surface, elastomeric half-mask of the respirator, which allows by processing and comparing the image with the reference image of the obturation strip to calculate the coefficient of tightness of the half-mask to the face. The iterative approach is based on solving the problem of minimizing the occurrence of leaks in the obturation band of the filter respirator that will reduce errors in the design of its geometric dimensions and avoid algebraic errors in their evaluation.

Scientificvalue. A method for measuring the surface temperature of the obturator with a thermal imager based on the processing of output signals has been developed, which allows for operational control of gaps along the obturation strip, detects deterioration of insulating properties of dust respirator and calculates its protection factor

Practical value. The proposed method allows you to quickly determine the conformity of the half mask to the face of the employee when performing various production operations. Provides control of the clamping forces of the elastomeric half mask of the respirator to the person's face when choosing it and will help reduce the suction of unfiltered air into the mask space.

Keywords: Half mask, thermogram, obturator, tightness factor.

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