What is the purpose of flashback arrestors in gas welding systems?

• A. To prevent flame from traveling back into hoses and regulators, protecting the gas supply.
• B. To increase flame temperature.
• C. To regulate pressure.
• D. To vent exhaust gases.

Answer: (A)

Flashback arrestors are safety devices that stop a flame from traveling back into the hoses and regulators if a flashback occurs. They typically use a check valve plus a heat-sensitive element that closes to prevent reverse flame flow, isolating the gas supply and protecting the regulators and cylinders from ignition or explosion. This protection is crucial in gas welding because a flame that travels back toward the gas source can cause a dangerous rupture or fire. They do not increase flame temperature, regulate pressure, or vent exhaust gases—those functions are handled by other components in the system. For best protection, install arrestors on both the fuel gas and oxygen lines near the torch and inspect them regularly.