After the oxygen is activated by opening the hood, two small cylinders provide the wearer cool fresh oxygen (not superheated oxygen like that from chemical generators). The Polyimide Film and PFA hood protects the crewmember's  head, eyes, neck and respiratory system completely from smoke, toxic fumes, heat, flying sparks and melting plastic parts. The integrated self sealing neck seal, seals comfortably around the users neck closing out toxic smoke and fumes providing a clean oxygen closed-loop breathing system.

Once the crewmember is wearing the Essex PBE they can then perform all required actions to extinguish a fire safely and immediately evacuate passengers.