Below are the regulations set by the MSA for material choice and sizes of tubes eligible for Roll cage and safety cell construction.
1.4.1. Specifications of the tubes used: Minimum Material Cold Drawn Seamless Unalloyed Carbon Steel, containing a maximum of 0.3% of carbon.
Note: For an unalloyed carbon steel the maximum content of additives is 1.7% for manganese and 0.6% for other elements.
Mandatory tubular members
45mm x 2.5mm (1.750″ x 12swg) or 50mmx 2.0mm (2.000” x 14swg).
38mm x 2.5mm (1.500” x 12swg”) or 40mm x 2.0mm (1.6” x 0.083”).(For roll cages/bars approved prior to 1.1.95).
Optional tubular members
38mm x 2.5mm (1.5” x 0.095”) or 40mm x 2.0mm (1.6” x 0.083”).
1.4.2. In selecting the steel, attention must be paid to obtaining good elongation properties and adequate weldability.
1.4.3. The tubing must be bent by a cold working process and the centreline bend radius must be at least three times the tube diameter. If the tubing is ovalised during bending, the ratio of minor to major diameter must be 0.9 or greater.
The tubes and brace(s) must have a diameter of at least 1.375″(35mm) and at least 0.090″ (2mm) wall thickness.
(ProFormance recommend ROPT510 1.500″ (38.1mm) x 12swg (2.6mm) to retain wall thickness over the 2mm minimum requirement during the bending process)