During an obstruction investigation, internal examination of sprinkler pipe should be performed at which areas?

Internal examination of sprinkler pipe during an obstruction investigation should encompass multiple key areas to ensure a thorough inspection. The riser, system valve, and cross main are critical components of the fire protection system that can potentially harbor obstructions, such as debris, rust, or coal material.

Starting with the riser, this is the vertical pipe that delivers water to the system, and blockages here can significantly affect water flow. Obstructions may accumulate at the base of the riser or simply be introduced to the system through the water supply.

Next, examining the system valve is crucial. This point controls the availability of water flow to the pipe system. Any obstructions or mechanical failures in this area may prevent proper operation during an emergency situation.

Lastly, the cross main is a horizontal pipe that distributes water to various branch lines connected to individual sprinklers. Obstructions can also occur in cross mains due to sedimentation or corrosion over time, which would impede the water supply to the sprinkler heads.

Conducting internal examinations at all three areas ensures that any obstructions are detected and rectified, maintaining the integrity and functionality of the fire protection system. Each of these locations plays a vital role in the overall performance of the system, which is why a comprehensive examination is necessary