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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.

Intertek is an OSHA (Occupational Safety & Health Administration) recognized NRTL (Nationally Recognized Testing Laboratory) in the U.S. and accredited as a Testing Organization and Certification Body by the Standards Council of Canada. We are also accredited by the International Accreditation Service (IAS), an International Code Council company.

  • Building Products Environmental Certification Program 
  • CE Mark 
  • ICC-ES Evaluation Reports 
  • ISMA Testing and Certification 
  • Marine Products Testing 
  • Miami-Dade County Testing


Warnock-Hersey Directory of Listed Products