Steel Thickness Range (mm and Gage)

49 CFR 178.503(a)(9)(i) requires metal drums that are marked with the nominal thickness of the metal used for construction to comply with the minimum tolerance thickness of ISO 3574 1986(E).  The below table documents the minimum dimension allowable per this standard.  The minimum tolerance varies depending on the size of the coil that the material is produced from.

Gage is a term that is normally used to describe the thickness of sheet steel.  The below table documents how Skolnik defines Gage and its correlation to the required markings.

 

Drum Marking	ISO 3574 (in)	ISO 3574 Minimum (in)	Skolnik Tolerance (in)	Gage No.
1.5	1.39 - 1.61	0.0547	0.055 0.063	16
1.2	1.11 - 1.29	0.0437	0.044 0.050	18
1.0	0.92 - 1.08	0.0362	0.037 0.042	119
0.9	0.82 - 0.98	0.0323	0.033 0.038	20
0.8	0.73 - 0.87	0.0287	0.029 0.033	22