HG/T 3240-2007 "Computer Film Thickness Gauges" specify the types, technical requirements, test methods, inspection rules, signs, Encasement, transportation and storage of battery-powered, digitally displayed computer film thickness gauges (hereinafter referred to as thickness gauges). This standard applies to thickness gauges for measurement of film thickness based on the principle of electromagnetic induction (magnetoresistance method) on magnetic materials (steel). The standard refers to a number of relevant specifications, such as General Technical Conditions for Instrument Encasement, General Principles of Instructions for Use of Industrial Products, and Instrument Transportation, Transportation and Storage Basic environmental conditions and test methods to ensure the operation specifications and Reliability of the thickness gauge in all aspects.