It’s easy, it’s on the label.
1. The label will state that garment meets ANSI 107-2015
2. The label will contain a pictogram showing HVSA type
•Type R, Type O, Type P
-If FR, must include specific standard used to evaluate flame resistance
•ASTM1506, 2733, 1891
•NFPA 1977, 2112
-If not FR, must state “Not FR” and site ANSI 107-2015 standard