16. Protective Padding:
16.1. Where the Driver’ s or Co-Driver’ s bodies or crash helmets could come into contact with the ROPS, nonflammable padding should be provided for protection.
16.2. It is recommended that rollbar / rollcage tubes within 150mm of a vehicle occupant’ s helmet are covered with a suitable energy absorbing material. Suitable materials are Homologated by the FIA who publish specific regulations for the fitment of such materials for Vehicles participating in International Event.
17. Removable Members:
17.1. Should removable members be used in the construction of a ROPS the demountable joints used must comply with an approved type( see App. 13 Diagram 30 to 38 and Diagram 46). The screws and bolts must be of adequate diameter and of ISO Standard 8.8 or better. FIA Homologated demountable joints are also permitted.
17.2. Demountable joints must not be used as part of a main, front or lateral rollbar because they act as hinges in the principal structure and allow deformation. Their use is solely for attaching members to the rollbars and for attaching a lateral rollbar to a main rollbar( see App. 13 Diagram 11). In this last case, hinged joints in App. 13 Diagram 30 to 38 and Diagram 46 must not be used.
18. Guidance on Welding
18.1. All welding should be of the highest possible quality with full penetration and preferably using a gas shielded arc.
18.2. Although good external appearance of a weld does not necessarily guarantee its quality, poor looking welds are never a sign of good workmanship.
18.3. When using heat-treated steel the instructions of the manufacturer must be followed( special electrodes, gas protected welding).
18.4. It is to be emphasised that the use of heat-treated or medium carbon steels may cause problems and that bad fabrication may result in a decrease in strength( caused by brittle heat-affected zones) or inadequate ductility.
19. Harness Bars
19.1. Minimum dimensions 38mm x 2.5mm or 40mm x 2.0mm. Cold Drawn Seamless Carbon Steel with minimum tensile strength of 350N / mm2. Harness straps may be attached by looping around the tube or by threaded fixings using inserts as drawing No. 44 welded into the tubes( s).
20. Material Specifications 20.1. Specifications of the tubes used:
a.
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. b.
Minimum Yield Strength 350 N / mm2 c. Minimum Dimensions( Ø in mm) i. Mandatory tubular members 45 x 2.5( 1.75” x 0.095”) or 50 x 2.0( 2.0” x 0.083”) 38 x 2.5( 1.5” x 0.095”) or 40 x 2.0( 1.6” x 0.083”).( For roll cages / bars approved prior to 1.1.95).
Motorsport UK National Competition Rules 2026 Edition 1
Chapter 7 Appendix 3- Roll Over Protection Systems( ROPS) 263