batteries and battery chargers; communication systems for respirators comprised of radio transmitters and receivers for use by an individual wearing a respirator; electronic monitors for monitoring gas and fire presence; detectors for gas, fire and flame; gas sensors; controllers for gas sensors; calibration stations comprised of electronic monitors for testing gas detectors and gas monitors; electronic detectors for detecting the presence of harmful chemical, biological, radiological and nuclear materials; fire alarms; thermal imaging cameras; air-purifying respirators not for medical purposes; powered air-purifying respirators not for medical purposes; self-contained breathing apparatus not for medical purposes; accountability systems for personal alert safety comprised of PASS (personal alert safety system) devices, radio transmitters and receivers; protective face shields and frames therefor; protective eyewear; safety goggles; safety glasses; sunshields in the form of polyurethane extensions which attach to headgear to protect the wearer's ears and neck from harmful sun rays; hearing protection headsets, ear muffs, ear bands, ear plugs and head bands all not for medical use; protective clothing to prevent bodily injury in the nature of safety vests; protective helmets; protective helmets for prevention of injury; fire helmets; winter liners for protective helmets; hoods, gloves and coveralls for protection against accidents; personal safety and fall protection equipment other than for sports, and not for use in vehicles, namely, full body harnesses, support belts for workers, lanyards, restraint lanyards, shock absorbing lanyards, self-retracting lanyards, lanyard shock absorbers, anchorage connectors, horizontal life lines, ladder climbing fall arresters, rescue cradles and rescue ladders; confined space entry and rescue equipment for fall protection of users, namely, self-retracting lanyards with retrieval capability, portable tripods and davits all for fall protection