Electrical testing
Communication cables
Sampling methods
Display devices
Performance testing
Electromagnetic compatibility
Telephones
Mechanical testing
Impact testing
Signals
Vibration testing
Temperature
Frequencies
Acoustic signals
Seatings
Type testing
Speech transmission systems
Colour-fastness tests
Dialling equipment (telephones)
Artificial ageing tests
Telephone equipment
Radio disturbances
Wear tests
Loudspeakers
Performance
Sensitivity
Drop tests
Communication equipment
Recording equipment
Telephone answering equipment