A closer look at Underwriters Laboratories UL 2158A and UL 181 classes
There is still a lot of misunderstanding and confusion about types of dryer venting and where they can and should be used. There have been many different products developed for venting dryers. With the introduction of aluminum foil, dryer venting manufacturers were able to make significant progress towards heat and flame resistance.
Our MFX48 semi-rigid aluminum duct is UL Approved and fire resistant to 435˚F
In December 2006, Underwriters Laboratories established UL 2158A “Clothes Dryer Transition Duct” which is an approved standard for flexible high temperature exhaust duct rated to 430 F˚ that can also be used on both electric and gas dryers. Only flexible ductwork meeting UL 2158A is safe for use as dryer venting.
There are also flexible vinyl and flexible aluminum pipes that have a UL listing of UL 181 “Closure Systems for Use with Flexible Air Ducts and Air Connectors”. This standard is for flexible plastic and metal heating, cooling ductwork and vent fans such as in your bathroom or kitchen. UL 181 and these products are not safe for use as a dryer vent.
Dundas Jafine products that fall under the UL 2158A and UL 181 categories:
