GB/T 17650.2-1998 Focusing cable or optical cable material combustion gas release acidity detection. It uses the measurement of ph value and conductivity to determine. First, the material is combusted, and the released gas is collected and dissolved in water. Then, the pH value of the solution is measured by acidity measurement, and the conductivity is measured by Conductivity Meter, and the gas acidity is obtained by a specific algorithm. The standard carefully specifies sample selection, combustion experimental device construction, instrument operation process and result calculation to ensure reliable data. The standard is of great significance for evaluating the environmental hazards of cable and optical cable combustion, and provides important technical support for product environmental protection and safety performance evaluation.