Module boilers operate more safely than conventional natural gas boilers. I. Differences in Combustion Methods Between Module Boilers and Conventional Natural Gas Boilers Module Boiler: Atmospheric direct combustion Vacuum phase-change gas boiler: Burner combustion method Conventional natural gas boiler: Burner combustion method II. Differences in Combustion Environments Between Module Boilers and Conventional Natural Gas Boilers Module Boiler: The combustion environment is semi-open around the bottom unit; even if deflagration occurs, it will not lead to an explosion. Vacuum phase-change gas boiler: The combustion environment is relatively sealed, with chimneys and explosion vents serving as pressure release points. There is a safety risk of explosion, and deflagration may potentially cause an explosion. In case of negative pressure failure, the boiler's safety mechanism relies on mechanical means such as sliding and bursting discs to maintain atmospheric pressure. Conventional natural gas boiler: The combustion environment is relatively sealed, with chimneys and explosion vents serving as pressure release points. There is a safety risk of explosion, and deflagration may potentially cause an explosion. The boiler is at atmospheric pressure and connected to the atmosphere. Note: Boilers using burner combustion methods pose safety hazards and may explode. For example, a natural gas heating boiler explosion in Furui Garden Community, Mangshan Road, Xingping, resulted in three immediate fatalities and three additional deaths despite rescue efforts.