Reference Source

UL 551

For UL 551, laboratory is TÜV SÜD America Inc; standard title is Transformer-type Arc-welding Machines, verified against its source on 2026-08-10.

Laboratory
TÜV SÜD America Inc. verified
Standard number
UL 551 verified
Standard title
Transformer-type Arc-welding Machines verified
Sourceosha.gov
Verified
Review by
DatasetWhich OSHA NRTL is recognized for which test standard: all 21 labs' scopes of recognition, cross-referenced

What the source says

UL 551 | Transformer-type Arc-welding Machines |

— osha.gov, retrieved 2026-08-10

Source

Last verified against source: . Due for re-check by . This page as Markdown · OKF bundle · full dataset as JSON.