Performanoe Evaluation of the Self-Contained Toxic Environment Protective Outfit - Interim (STEPO-I) System

摘要

A quantitative protection factor (PF) evaluation was conducted on the Interim Self-Contained Toxic Environment Protective Outfit (STEPO-I). The STEPO- I is a protective ensemble consisting of a fully encapsulating suit with two alternative breathing and cooling systems. The suit is made of an impermeable, butyl rubber-coated nylon. The respirators consist of a closed-circuit breathing apparatus and a tethered airline emergency breathing apparatus. The closed- circuit breathing apparatus is worn with a battery-powered ice vest to provide cooling. The tethered air line emergency breathing apparatus vents a portion of the airline pressure to the wearers' extremities for blown-air cooling. Quantitative PF testing was conducted on each of the respirators and on the suit. Protection factor testing of the breathing apparatuses was conducted without the encapsulating suit to ensure a uniform challenge atmosphere. Both respirators performed very well due to their positive pressure. The suit was tested while worn over each of the respirators. The results showed that the vented air in the tethered airline mode provided a high degree of protection inside the suit. However, the closed circuit breathing apparatus does not vent off much air, and it was discovered that a significant flow of the challenge aerosol was entering the suit while in this mode.