Safety Alert Number 0701010

Underwriters Laboratories Issues Warning over Counterfeit Sprinklers

Despite the concerted efforts of Underwriters Laboratories Inc. (UL), manufacturers, distributors and building owners, UL has received a number of reports of counterfeit fire sprinklers found outside North America. At this time, UL has received no reports of counterfeit fire sprinklers found within the United States or Canada. UL is notifying regulatory authorities to be vigilant regarding fire sprinklers that may potentially bear counterfeit UL Marks. These fire sprinklers have not been evaluated by UL to determine compliance with UL's safety requirements.

In many cases, extensive knowledge of the construction features of an authentic UL Listed fire sprinkler is needed to identify a counterfeit fire sprinkler. However, there are three basic features that all UL Listed fire sprinklers must have.

UL Listing Mark

The easiest way to verify a UL Listed fire sprinkler is to look for the UL Listing Mark. All UL Listed fire sprinklers must be marked with the UL symbol. In addition, all four elements of the UL Listing Mark, described as follows, shall be provided on the smallest unit container in which the product is packaged, such as the carton:

1. The UL symbol
2. The word "LISTED"
3. The product name, which is described in the Guide Information
4. A control number, which is used internally by UL for factory follow-up purposes

For larger products, all four elements of the UL Mark usually appear on the product itself. However, because fire sprinklers are so small, only the UL symbol appears on the product.

Protective cover

Another means of identifying a counterfeit product is the lack of a protective cover that must be provided on each individual fire sprinkler that utilizes a glass bulb heat-responsive element.

As of March 26, 2004, UL Listed fire sprinklers designed with a glass bulb heat-responsive element are required to have a protective cover when they are shipped from the manufacturer, and should be attached to the product during installation. This requirement is mandatory for all UL Listed fire sprinklers that have a glass bulb heat-responsive element.

UL's investigation of counterfeit fire sprinklers has revealed that some counterfeit products are being shipped without the required protective cover.

Sprinkler Identification Number (SIN)

A final method to identify a counterfeit fire sprinkler in the field is to verify the Sprinkler Identification Number (SIN). Effective Jan. 21, 2001, all UL Listed fire sprinklers under the product categories "Sprinklers, Automatic and Open (VNIV)," "Residential Automatic Sprinklers (VKKW)" and "Sprinklers, Early Suppression Fast Response (VNWH)," are required to be marked with a SIN. The SIN is an alphanumeric sequence that provides a means to identify the manufacturer, and determine operating characteristic information about the fire sprinkler, such as K-factor and response type.

If a fire sprinkler is not marked with a SIN, it has not been certified by UL.

To verify a SIN, visit:

and click on "Sprinkler Identification Number (SIN) Database. "

If there is suspicion or concern regarding the authenticity of a fire sprinkler, you are encouraged to contact UL or a representative of the fire sprinkler manufacturer. To report counterfeit fire sprinklers, use UL's online Field Report Form at:

You will be contacted and requested to provide samples, along with information regarding the origin of purchase. For more information on UL Listed fire sprinklers, contact Kerry Bell in Northbrook, Ill. , by phone at +1-847- 664-2629, or by e-mail at:

For photos of sprinklers and more info, click below: