The Air Quality Meter Gasman-PH3 is a unique gas meter which protects against a specific gas, inflammable or toxic. The Air Quality Meter warns with a penetrating alarm and an optical signal (useful in case when there are loud noises in the surroundings) of the existence of dangerous gas concentrations and shows on screen the value of the gas measurement. All the test instruments come manufacturer calibrated. ISO certification can be made as an option.