Red Seal Gasfitter — Class B Practice Exam

What is an example of a non-combustible material used in gas venting?

1. PVC

2. Fiberglass

3. Wood

4. Paper

The correct answer is: PVC

The correct answer represents a non-combustible material frequently utilized in gas venting applications. Specifically, PVC (polyvinyl chloride) is widely recognized for its resistance to combustion and ability to withstand various chemical exposures, making it suitable for venting applications within gas systems. In the context of gas venting, using materials that can tolerate high temperatures and prevent ignition is crucial for ensuring safety and compliance with building codes. PVC, particularly when appropriately rated and installed, can effectively handle the conditions present in venting scenarios, serving as a reliable option for exhaust pipes in certain applications. While fiberglass is often regarded for its insulating properties, it is not usually classified as non-combustible under certain conditions and may not be suitable for direct venting of gas appliances. Wood and paper, being combustible materials, would present significant fire hazards in gas venting systems, which necessitates the use of materials that resist burning and can ensure safe operation.