Technical Standards and Safety Authority (TSSA) G3 Practice Exam

What safety feature is typically found in a purge burner?

1. Able to shut off gas automatically

2. Equipped with a flame arrestor

3. Self-cleaning mechanism

4. Circulating fan for better heat distribution

The correct answer is: Equipped with a flame arrestor

A purge burner is specifically designed to ensure the safe operation of gas burners by preventing the accumulation of uncombusted gas and minimizing the risk of explosive mixtures forming in the combustion chamber. One key safety feature of a purge burner is the flame arrestor, which acts as a barrier to prevent flames from propagating back into the gas supply lines. This is crucial for safety as it reduces the risk of a fire or explosion should a flashback occur. The flame arrestor typically consists of a metal mesh or series of baffles that absorb the energy of a flame and heat, effectively stopping it from traveling backwards. This mechanism provides a critical layer of protection in applications where gas is being purged prior to ignition, ensuring that the system remains safe during the purging process. Other features like automatic gas shut-off or self-cleaning mechanisms may be beneficial but are not the primary safety characteristic specifically associated with purge burners. Hence, the flame arrestor is a defining feature that enhances the overall safety of the operation.