Warnock Hersey Mark
The Warnock Hersey Mark, issued by Intertek, is North America’s most
recognized product safety and performance mark for building products.
Building and construction materials bearing the WH Mark indicate to your
customers and end-users that your product has complied with relevant building
codes and association criteria as well as product safety and performance
The mark also signifies that the product’s manufacturing site(s) undergo
periodic follow up inspections to ensure the ongoing compliance of the
originally certified product. In short, a field inspection consists of line
sampling and inspection to ensure that the product continues to be manufactured
in the same manner as the product which was originally certified.
A WHI Mark with a “US” identifier at the 4 o’clock position indicates that the
product meets US standards. A WHI Mark with a “C” identifier at the 8 o’clock
position indicates that the product meets Canadian standards.
Today, the mark appears on thousands of building and construction products,
from hearth products and fenestration materials to hardware, manufactured wood,
fire extinguisher cabinets, access panels,
plumbing, roofing, and various other products such as pools and spas.