Gas alarms; parts and accessories for gas alarms; gas alarms having telecommunication functions in the nature of wireless transmitters and receivers, and downloadable computer application software for use therewith; gas leak alarms; parts and accessories for gas leak alarms; gas leak alarms having monitoring functions; gas leak alarms having telecommunication functions in the nature of wireless transmitters and receivers; fire alarms; parts and accessories for fire alarms; smoke alarms; gas incomplete combustion alarms; air pollution indicator alarms; gas detectors for detecting the presence of gas; parts and accessories for gas detectors for detecting the presence of gas; gas detectors having telecommunication functions in the nature of wireless transmitters and receivers, and downloadable computer application software for use therewith; fire detectors; smoke detectors; heat detectors; odor detectors; formaldehyde detectors; gas detection alarms; alarm systems comprised primarily of detector unit and their parts and accessories; gas alarm systems comprised primarily of detector unit and their parts and accessories; alarm systems comprised primarily of detector unit, indicator unit and communication unit for detecting and alerting the presence of gas, smoke, sparks, fire, odor or heat, and their parts and accessories; detectors for use with alarm system for detecting and alerting the presence of gas, smoke, sparks, fire, odor or heat; indicators for use with alarm system for detecting and alerting the presence of gas, smoke, sparks, fire, odor or heat; communication apparatus in the nature of wireless transmitters and receivers for use with alarm system for detecting and alerting the presence of gas, smoke, sparks, fire, odor or heat; gas leak alarm systems comprised primarily of detector unit having monitoring functions and their parts and accessories; gas leak alarm systems comprised primarily of detector unit having telecommunication functions and their parts and accessories; centralized monitoring alarm systems comprised primarily of detector unit for multiple gas leak alarms installed separately and their parts and accessories; centralized gas monitoring alarm systems comprised primarily of detector unit having gas circuit breaker and ventilator, and their parts and accessories; centralized gas monitoring alarm systems comprised primarily of detector unit having telecommunication functions and their parts and accessories; centralized monitoring alarm systems comprised primarily of detector unit for detecting abnormal vibration and temperature rise in electric motors and motors, and their parts and accessories; centralized monitoring alarm systems comprised primarily of detector unit for detecting abnormal vibration, temperature rise, gas and oil leak in pumps with rotating machine, and their parts and accessories; monitoring alarm systems comprised primarily of detector unit for security and disaster prevention and their parts and accessories; gas alarm systems comprised primarily of gas detector for detecting the presence of gas, signal processing unit and control unit; gas measuring apparatus; gas analyzers for measuring gas concentration; gas testing instruments; chemical exposure meters for measuring chemical exposure; odor measuring apparatus; measuring apparatus for measuring the concentration of steel dust; measuring apparatus for measuring the concentration of formaldehyde; gas sensors for measuring gas concentration; gas sensors for detecting the presence of gas; sensor units for gas concentration measuring machines and instruments comprised primarily of circuit boards and gas sensors; sensor units for gas detectors comprised primarily of circuit boards and gas sensors; interchangeable sensor units for gas detectors; apparatus and instruments for testing and checking the operation of gas detectors, and downloadable computer software for use therewith; security control and monitoring systems comprised primarily of gas detector, monitoring unit, microcomputer, display and control unit; gas monitoring systems comprised primarily of gas detector, signal processing unit and monitoring unit, for detecting gas leak; gas detectors for environmental control; gas controlling systems comprised primarily of gas alarms and wireless communication apparatus for shutting off gas supply; wireless communication apparatus for transmitting and receiving signal to and from gas detectors and gas meters to shut off gas supply; electrical signal converters for gas alarm; telecommunications apparatus in the nature of wireless transmitters and receivers and their parts and accessories; electronic data readers for use with gas detectors, namely, electronic card readers; electronic data readers for use with gas alarms, namely, electronic card readers; electronic data readers for use with gas measuring apparatus, namely, electronic card readers; power distribution or control machines and apparatus in the nature of electric controller; rotary converters; phase modifiers; personal digital assistants

Installation, repair and maintenance of alarms, security systems and inspection systems; installation, repair and maintenance of alarms for alerting the presence of gas, smoke, sparks, fire, odor or heat; installation, repair and maintenance of fire alarms; installation, repair and maintenance of detectors for detecting the presence of gas, smoke, sparks, fire, odor or heat; installation, repair and maintenance of alarms for detecting and alerting the presence of gas, smoke, sparks, fire, odor or heat; installation, repair and maintenance of monitoring alarm systems for security and disaster prevention; installation, repair and maintenance of electronic machines and their parts and accessories; installation, repair and maintenance of telecommunications apparatus and their parts and accessories; installation, repair and maintenance of electric motors; installation, repair and maintenance of power distribution or control machines and apparatus; installation, repair and maintenance of electricity generators; installation, repair and maintenance of measuring or testing machines and instruments