The Dryer Vent Safety Council Podcast

Why Is My New Clothes Dryer Still Taking Too Long to Dry The old dryer left the house. The old problem didn’t. A new appliance connected to the same clogged dryer vent can leave you with the same damp laundry.

Learn what an outdoor damper, unusually little lint on the screen, and airflow warnings can reveal. We also explain an optional electric dryer only diagnostic comparison and why crushed transitions or unsuitable vent materials may require more than cleaning.

Know what to ask for when arranging professional service, including a complete system inspection and performance testing before and after service to verify the results.

Dryer Vent Safety Council | Consistency Reduces Risk.

For more information visit:http://www.dvsafe.org/

Distinguished Achievement Awards Presented for Landmark Fire Code Contributions

PRESENTATION — BRIGHTON, MI — OCT 10, 2026

During the Brighton Area Fire Authority’s annual open house, two fire officers received special recognition for helping bring clothes dryer provisions into the International Fire Code.

On behalf of the Dryer Vent Safety Council, Scott Thomas, Dryer Vent Wizard International Field Training Manager, and Tim Reiher, owner of Clean & Green Dryer Vent Experts,presented Distinguished Achievement Awards to Chief Richard Boisvert and Chief Michael OBrien.

“The Dryer Vent Safety Council, Dryer Vent Wizard, and Clean & Green Dryer Vent Experts appreciate your efforts in fighting the good fight to get the fire code changed — something near and dear to our hearts: cleaning dryer vents and keeping folks safe.” — Scott Thomas

“Their contributions represent the kind of fire prevention work whose greatest success may be a fire that never occurs.” — Tim Reiher, Senior Technical Advisor, Dryer Vent Safety Council

Dryer Vent Safety Council | Consistency Reduces Risk.

www.DVSafe.org

The Federal Disagreement Over Clothes Dryer Airflow examines why the U.S. Department of Energy deliberately restricts the exhaust of vented clothes dryers during standardized laboratory testing and how the AHAM Standard Simulator has been part of federal dryer testing since 1977.

The episode follows an unusual technical trail involving the Standard Simulator, the Modified Exhaust Simulator, and three similar openings: 2 9/16 inches, 2 7/8 inches and 2 11/16 inches. Those fractions became consequential when field airflow research led utilities to ask DOE whether its laboratory exhaust condition should better represent residential dryer vent conditions.

Most importantly, the episode explains the boundary between laboratory testing and field measurement. The AHAM simulator establishes a controlled exhaust restriction for repeatable testing. It does not establish a universal residential back pressure, airflow or equivalent dryer vent length. Understanding that distinction helps explain why the actual operating conditions of an installed dryer and dryer vent still matter.

Dryer Vent Safety Council | Consistency Reduces Risk.

For more information visit:http://www.dvsafe.org/

Fire Prevention Month | October 2026 — Two Fire Officers. One Landmark Code Change. traces the history of fire prevention from the Great Chicago Fire of 1871 to a modern effort to address clothes dryer maintenance in the International Fire Code. It is a story about an important side of fire safety that is often difficult to measure: the fires that never happen.

In 2018, Fire Marshal Richard Boisvert identified a gap in the International Fire Code and proposed clothes dryer installation and maintenance requirements. After the initial proposal was disapproved, Fire Chief Michael O’Brian helped advance revised language that ultimately passed 287 to 79 and became Section 610, Clothes Dryer Exhaust Systems, in the 2021 International Fire Code.

During Fire Prevention Month, the Dryer Vent Safety Council recognizes Boisvert and O’Brian with its Distinguished Achievement Award for their contributions to clothes dryer maintenance provisions in the International Fire Code. Their story is a reminder that prevention can begin with an inspection, a maintenance requirement, or a code proposal, and its greatest success may be an incident that never occurs.

Dryer Vent Safety Council | Consistency Reduces Risk.

For more information visit:http://www.dvsafe.org/

Association of Home Appliance Manufacturers (AHAM) — Inside Its Dryer Vent Safety Guidance examines what AHAM says about dryer installation, airflow, maintenance and cleaning, including its recommendation for annual professional cleaning of both the appliance interior and venting system.

The episode goes inside ANSI/AHAM HLD 1 and the AHAM Standard Simulator, a device used to create a controlled exhaust restriction during laboratory dryer testing. The U.S. Department of Energy incorporates this simulator into the federal clothes dryer test procedure, providing nearly 50 years of history showing that exhaust restriction is a controlled variable in standardized dryer performance testing.

AHAM does not establish universal field CFM, exterior velocity or dryer vent back pressure thresholds. Instead, the episode separates laboratory testing from field evaluation and explains the DVSC principle that a residential dryer vent should be evaluated as an airflow system, not merely as a vent that may contain lint.

Dryer Vent Safety Council | Consistency Reduces Risk.

For more information visit:http://www.dvsafe.org/

Long Radius Dryer Exhaust Elbows — Why Geometry Matters examines why two 90 degree elbows can have dramatically different effects on a clothes dryer exhaust system. The 2024 International Residential Code assigns 5 feet of equivalent length to a 4 inch radius mitered 90 degree elbow, but only 1 foot 6 inches to a 10 inch radius smooth 90 degree elbow. The difference is geometry.

Follow the engineering and code history behind long radius elbows, from a 2004 engineering analysis through a 2006 UL fact finding investigation and the development of today’s ICC fitting tables. The episode also explains the one to one principle, where a qualifying 10 inch radius smooth elbow can have an equivalent length corresponding to its actual physical length.

Reducing fitting resistance can preserve valuable allowable duct length and, in some system designs, may mean a powered device is not needed at all. But elbow geometry is only one part of the complete exhaust system, and dryer manufacturer instructions and applicable local requirements still control.

Dryer Vent Safety Council | Consistency Reduces Risk.

For more information visit:http://www.dvsafe.org/

Dryer Exhaust Wall Receptacles — What the Codes Tell Us examines the small but important space behind a clothes dryer and how a wall receptacle can help protect the exhaust connection, provide needed clearance and, in some installations, eliminate an unnecessary elbow.

The episode follows the technical history behind these receptacles through the 2024 International Residential Code, ICC code development and engineering opinions involving cleanout access and duct shape. It also explains why equivalent length depends on elbow geometry and why eliminating an elbow does not automatically add the same amount of allowable duct length in every installation.

Using Dryerbox as a documented technical example, the discussion examines UL Through Penetration Firestop System WL 7129 and the important distinction between a product and a defined fire resistance assembly. The practical lesson is straightforward: plan the connection around the actual dryer, manufacturer instructions, exhaust route and applicable code requirements.

Dryer Vent Safety Council | Consistency Reduces Risk.

For more information visit:http://www.dvsafe.org/

Clothes Dryer Manufacturers Require Quantifiable Exhaust Performance examines how dryer manufacturers use measurable criteria to evaluate exhaust system performance. Technical literature from all major manufacturers addresses static pressure, back pressure, airflow, air velocity, pressure loss and exhaust system resistance.

Manufacturers do not prescribe one universal test, instrument or acceptable reading. Some specify a manometer, while others quantify airflow, pressure loss or resistance through duct length, bends and elbows. The common engineering principle is clear: dryer exhaust performance can be evaluated quantitatively, while physical inspection helps identify conditions that may explain the results.

This episode also connects manufacturer technical literature with the 2024 International Fire Code and International Property Maintenance Code and explains DVSC’s recommended professional methodology: Measure. Inspect. Diagnose. Service. Measure again. Measurement tells us how the system is performing. Inspection helps tell us why.

Dryer Vent Safety Council
 Consistency Reduces Risk.

For more information visit:http://www.dvsafe.org/

Journey Through UL 1240 — What Keeps Electric Commercial Clothes Drying Equipment Safe? explores an important distinction: a dryer installed in a commercial location does not automatically fall under UL 1240. The intended user matters. UL 2158 can apply to dryers intended for the general public, while UL 1240 covers certain commercial, industrial and institutional clothes drying equipment intended for trained or supervised personnel.

The episode also explains why UL 1240 is a product safety standard, not a commercial dryer exhaust duct design standard. Manufacturer instructions, adopted mechanical codes and other applicable requirements can govern different parts of the same installation. Commercial exhaust systems can vary substantially in duct size, airflow, allowable pressure, makeup air and configuration.

For technicians, one lesson is especially important: pressure numbers need context. A reading only becomes meaningful when you know the machine, measurement location, operating condition and manufacturer specification. From makeup air and common exhaust systems to secondary lint collectors and replacement equipment, the complete installation must be evaluated for the specific dryer.

Dryer Vent Safety Council
  | Consistency Reduces Risk.

For more information visit: http://www.dvsafe.org/

How Many Times a Year Do We Use Our Clothes Dryer? explores how dramatically dryer use can vary from one household to another. ENERGY STAR estimates about 300 laundry loads per year for the average American family, while U.S. Department of Energy research using 2020 Residential Energy Consumption Survey data estimated 213 dryer cycles per year.

The episode looks inside the data, including the 18,496 households that responded to the 2020 survey, differences by household size, and a Northwest Energy Efficiency Alliance field study that directly metered dryer operation. It also explains why laundry loads, standardized test values and household use estimates are different measurements that should not be treated as interchangeable.

For dryer vent maintenance, time and use are not the same thing. DVSC recommends professional dryer vent cleaning generally every 250 to 500 dryer cycles, with system configuration, measured performance, inspection findings, manufacturer instructions and other conditions also considered when determining an appropriate interval.

Dryer Vent Safety Council
 Consistency Reduces Risk.

For more information visit: http://www.dvsafe.org/