Warnock Hersey (WH) Mark

The Warnock Hersey Mark (WH) is North America’s leading product safety and performance mark for building and construction products.

Products bearing the WH Mark indicate compliance to relevant building codes, association criteria, and product safety and performance standards. Nearly 80% of North America's wood fire-rated doors bear the WH Mark. 

Intertek’s Warnock Hersey (WH) Mark has long been the building product industry’s preferred certification mark. The WH Mark can be found on more than 6,500 products ranging from fire doors and builders’ hardware to hearth, plumbing and construction products.  Having Intertek’s WH Mark on your product reflects your commitment to product safety, performance and quality to inspectors, builders and end users. The mark also signifies that the product’s manufacturing site(s) undergo periodic follow-up inspections to ensure ongoing compliance of the originally certified product. 

Our testing and certification services include:

• Fire Testing 
• Field Labeling of Fire Doors 
• Physical Property Testing
• Fenestration Testing 
• Weathering Testing 
• Structural Testing
• Performance Testing 

Testing Standards for the WH Mark
We test your products to applicable ANSI, UL, ASTM, CCMC, CSA, EPA, ICBO, and ULC standards.

Accreditations
Intertek is recognized by the world's leading code bodies; as a Nationally Recognized Testing Laboratory (NRTL) by OSHA; recognized by Standards Council of Canada (SCC); and A2LA, APLAC, and ILAC accredited for Asia and other parts of the world. Our additional accreditations include those by the Standards Council of Canada (SCC), the National Evaluation Service (NES), the American National Standards Institute (ANSI) and the International Code Council - Evaluation Service (ICC-ES).

Request more information to see how Intertek can help your organization with Warnock Hersey (WH) Mark.