How far must smoking, open flames, or ignition sources be from the point of transfer while filling operations are in progress?

The correct answer is based on safety regulations concerning the handling of LP-gas during filling operations. Maintaining a distance of 25 feet from smoking, open flames, or other ignition sources is critical to minimize the risk of fire or explosion. LP-gas is highly flammable, and even small sources of ignition can cause an incident when transferring gas. The established safety distance helps to create a buffer zone that reduces the likelihood of ignition of gas vapors, which can be present during filling operations.

This regulation is part of broader safety measures designed to protect both workers and the public from the hazards associated with LP-gas. In practice, this means that all personnel involved in the transfer process need to be vigilant about keeping these ignition sources outside the designated safe distance to ensure that their operations remain safe and compliant with regulations.