Technician Team Test No. 7 Taken from the 2016 National Technician Team Contest (BioPak) held in Reno, NV Progress Indicator: Question 1 of 30 1.  The BioPak 240R and 240S breathing apparatus is best described by NIOSH to be: Choices: Open-Circuit, On Demand, Entry and Escape Self Contained Breathing Apparatus Close- Circuit, On Demand, Escape Only Self Contained Breathing Apparatus Semi-Closed Circuit, Pressure Demand, Entry and Escape Self Contained Breathing Apparatus Closed-Circuit, Pressure Demand, Entry and Escape Self Contained Breathing Apparatus