SOLID PARTICLE PENETRATION INTO ENCLOSURES

Protection factors against toxic vapors for enclosures such as vehicle s and shelters are commonly evaluated on the basis of the behavior of a simulant vapor. Mechanisms influencing protection against solid part icles have yet to be integrated into integrity-testing procedures. The scarcity of empirical studies which could provide the basis for such procedures suggested a program whose objectives would be to provide me ans for measuring size-dependent solid particle protection factors for various exposure scenarios and for expressing the relevant mechanisms in model calculations. These could then aid in the design of such pro cedures. A system providing a flexible infrastructure for experimentin g with controlled challenge scenarios was assembled outdoors in an ope n-ended agricultural cloche. A sealed enclosure located at the end of the cloche far from the dissemination apparatus enabled testing of sol id particle challenge penetration through well-defined apertures under controlled ventilation dynamics. A computer model was written to calc ulate protection factors for vapor and solid particles using both theo retical models and empirical data. The experimental system provided da ta for the calibration and verification of the model.