BS EN 50058:1999 Electrical apparatus for the detection and measurement of combustible gases. Performance requirements for Group II apparatus indicating up to 100% (V/V) gas
1999BS EN 50058:1999 Electrical apparatus for the detection and measurement of combustible gases. Performance requirements for Group II apparatus indicating up to 100% (V/V) gas
1991BS EN 50058:1991 Specification for electrical apparatus for the detection and measurement of combustible gases. Performance requirements for Group II apparatus indicating up to 100 % (V/V) gas