Can combustible gas detectors using catalytic combustion detect all types of gases?

Not all either; catalytic combustion of O2 and CO2 cannot be measured. It’s best for you to consult the manufacturer’s technical staff on this

1. Theoretically, catalytic combustion reacts with all flammable gases; catalytic combustion sensors are not suitable for detecting \"heavier\" or long-chain alkanes, especially those with a high flash point. Using a photoionization detector at this time might be a good approach. Hands-on testing at the site showed that catalytic combustion responds very slowly, or even shows no reaction, to organic compounds such as benzenes, lipids, alcohols, and amines. For organic combustibles like these, testing them as flammable gases is just to meet security requirements; if actual measurement is needed, the PID principle must be used to determine ppm levels, but the cost is several times higher. 2. In reality, many manufacturers also test it as a combustible gas, mainly due to cost considerations related to safety inspections; it’s fine to test it as a combustible gas as well. 3. Combustible gases are now subject to **CCC mandatory certification**; as long as you purchase legitimate meters from the market, they will be calibrated for methane in accordance with CCC requirements, and not for ethanol. In an absolute sense, measuring the levels of these gases as you mention is certainly not accurate, but gas detectors are not designed to provide precise numerical values; it’s sufficient as long as they can give an early warning, so a slight inaccuracy is acceptable.