The Occupational Safety & Health Adjustment (OSHA) affiliated with the U.S. Department of Labor requires that industrial products used at industrial sites be certified by state-approved laboratories for the safety of workers.
The NRTL currently has 18 agencies (UL, CSA, TUV, ITSNA, and so on).
Domestic companies that want to export to the U.S. will meet U.S. legal requirements regarding safety certification if they obtain the certification mark of one of these 18 national testing centers.

NRTL uses a registered mark by NRTL testing agency to approve that the product meets the OSHA product approval requirements. However, because the NRTL sometimes uses the same or similar mark as the registered NRTL mark, which is not intended to be OSHA, the NRTL mark shown in the product does not necessarily meet OSHA requirements.
OSHA only recognizes products that are certified by NRTL within the scope of certification and that have NRTL marks on the product. Each NRTL has its own scope of certification and can extend the scope of certification through a certain verification procedure if necessary.
NRTL certification can be carried out through MOUs with NRTL agencies in the U.S.

Products requiring NRTL certification as specified by OSHA include:
▶Fire prevention and evolution equipment: automatic sprinkler systems, fire extinguishers (dry chemicals, sprayers, bubbles, gas-material drugs, etc.) Fire extinguishers, fire alarms, fire doors, heat-detection devices, hoses, etc.
▶ Gas equipment: LPG-related equipment, LPG-handling equipment, and machinery such as LPG storage, valves, pipes, etc.
▶ Products used in hazardous environments with risk of explosion (bulk products)
▶Electronic products
Application Specifications: Product Safety Standards applied by NRTL are ANSI (American National Standards Institute), ASTM (American Society for Testing Materials), Factory Mutual Research Corporation (FM), UL (Underwriters Laboratories) ProtectionAccording to meet legal requirements by product, etc.

Each institution carries out a follow-up audit based on its own criteria.
We usually conduct a follow-up review about four times a year.