Which statement about a clothes dryer moisture exhaust vent is correct? A) Should be secured by sheet metal screws B) Can be common vented into a vent connector or chimney C) If flexible metal venting is used, it must be fully extended and supported D) Flexible metal venting should be as long as possible

What this question is really testing

Dryer vents are a fire and moisture issue. The right choice is the one that reduces restrictions, prevents lint from catching, and keeps the exhaust separate from other venting systems.

Checking each option against safe venting practice

A) Secured by sheet metal screws Not recommended, because screws can protrude into the duct and catch lint, creating a clog and increasing fire risk. Joints are typically fastened with approved clamps or foil tape methods allowed by local code.

B) Common vented into a vent connector or chimney Wrong. Dryer exhaust is generally required to terminate outdoors and is not allowed to discharge into chimneys, gas appliance vents, attics, crawlspaces, or other shared vent connectors. It adds lint and moisture, which can damage systems and create hazards.

C) Flexible metal venting must be fully extended and supported Correct. Flex duct creates more resistance than smooth rigid metal, so if it is used it should be pulled tight (fully extended), routed to avoid sagging and crushing, and supported so it does not kink.

D) Flexible metal venting should be as long as possible Wrong. Dryer vent runs should be as short and straight as practical. Longer runs increase pressure loss and lint accumulation, and they can exceed the dryer manufacturer and code length limits.

Quick rule to remember

Less restriction equals less lint buildup: use the shortest, straightest run you can, and if flex is used, keep it fully extended and supported.