Gas piping with fuel gas lighter than air, exceeding 5 psi, must be vented in which manner?

When dealing with gas piping that carries fuel gas that is lighter than air and exceeds pressure levels of 5 psi, the correct procedure is to vent it directly into the chase. This method is based on safety considerations to manage the potential hazards associated with the gas.

Chases are vertical spaces in buildings designed for the passage of utilities such as pipes and ductwork. Venting gas into a chase allows for adequate dispersion and ventilation within a controlled space, minimizing the risk of gas accumulation that could lead to dangerous situations like explosions or asphyxiation.

The other options might not adequately address safety concerns related to gas handling. For instance, venting directly to the outdoors is often appropriate for certain applications, but in high-pressure scenarios, the precise management of gas dispersion is critical; hence, the chase is preferable. Venting into buildings or through floors increases the likelihood of gas exposure in living or working areas, which is unsafe. Proper venting practices are essential in ensuring overall safety and compliance with established codes.