Gas and hazardous vapors detectors and parts thereof; gas and hazardous vapors measurers and parts thereof; gas and hazardous vapors analyzers and parts thereof; gas and hazardous vapors monitors and parts thereof; gas and hazardous vapors data recorders and parts thereof; gas calibrators for calibrating gas in gas detectors; downloadable software for use with gas detection, gas calibrators, vapor, gas, fire, and danger alarms, measurement and analysis, fire and danger alarms, plume modeling, thermal imaging, flame detection, respiratory protection, fall detection; thermal imaging cameras; respiratory protective apparatus, namely, escape respirators, air-purifying respirators, air-line respirators and self-contained breathing apparatus and parts thereof; eye and face protective apparatus, namely, masks, safety goggles, safety glasses and face shields; communications systems comprised of transmitters and receivers associated with radio, wireless and wireless network communications and telemetry, voice amplifiers and transmitters; personal alert safety systems comprised of sensors for surrounding conditions or physical conditions of the user, namely, sensing chemical gas, detecting gas connectivity and sensing capability and presence of gas, sensing of compliance with system component usage guidelines and system parameters or connection to safety monitoring systems and telecommunications transmitters to notify others that a user is in distress or a dangerous condition has been encountered; fall detection systems and apparatus, namely, personal emergency response systems featuring location determination and geo-fencing; Protective ear covering shields, namely, earmuffs incorporating hearing protection; protective wearing apparel for miners, industrial workers, firefighters and those engaged in hazardous pursuits, namely, hard hats, caps, winter headwear, and hoods for protection against accident and fire; ballistic resistant helmets; personal safety and fall protection equipment for fall restraint and fall arrest, other than for sports, namely, full body harnesses, support belts for workers, lanyards, restraint lanyards, shock absorbing lanyards, self-retracting lanyards, lanyard shock absorbers and anchorage connectors; rope grabs; ladder climbing safety equipment, namely, ladder fall arresters; confined space entry and/or retrieval equipment for safety purposes for fall protection, namely, personnel and material handling hoists, guard rails, self-retracting lanyards with retrieval capability, portable tripods and davits; safety horizontal lifelines; and safety vertical lifelines and descent devices that lower people at a controlled rate of speed