TÜV Rheinland of North America (TRNA) is – like UL and further organizations in the US - a NRTL and performs product safety tests and certifications for the US-Market.

As appropriate authority for the safety of machinery in the US, OSHA (Occupational Safety and Health Administration) requires certification of components used in plant and machinery acc. to the American product safety standards. Only testing laboratories accredited by OSHA - so called NRTLs (Nationally Recognized Testing Laboratory) - can perform these tests and certifications.