Major Standards

FMCSA Part 399, Subpart L – The Federal Motor Carrier Safety Administration (FMCSA) has promulgated 49 CFR (DOT), Part 399, Subpart L, (circa 1982) for cab-over engine (COE) highway tractors. It prescribes step, handhold, and deck requirements for commercial motor vehicles, with the intent of enhancing the safety of motor carrier employees. Although few cab-over-engine trucks are currently produced or used in the U.S., many heavy truck manufacturers reference FMCSA standard for all of their heavy truck configurations. Section 399.205 defines handholds, fingertip grasps, and full grasps. Section 399.207 defines “three points of contact”, step design to accommodate two feet, and slip resistance of steps. Section 399.207 also defines handhold dimensions, locations, and static loading requirements. Section 399.211 defines I/E Systems maintenance requirements.

TMC RP-404B – The Technology and Maintenance Council of the American Trucking Associations has created the recommended practice RP-404 B to enhance the safety of motor carrier employees by providing guidance regarding the use of access systems on heavy trucks and truck tractors and by developing design criteria to meet the performance objectives of the driver. RP-404 B defines “three points of contact”, step and handhold design criteria, climbing methods, and future improvements. [Contact TMC to obtain this copyrighted recommended practice.]

SAE J185 – The Society of Automotive Engineers (SAE) first published SAE J185 in 1970. This landmark recommended practice defined ingress and egress assist equipment, for climbing irregular vertical surfaces to the operator’s cab, such as those found on construction and industrial vehicles. SAE J185 was revised in 1981, 1985, and in 1988. Although J185 is not explicitly applicable to on-highway vehicles, many vehicle manufacturers reference its recommendations. SAE J-185 also defines steps, handholds, “three points of contact”, step height, step slip resistance, and handhold spacing. The 1988 revision recommends the coordination of steps and handholds to minimize foot slippage and to promote an “actively self-evident” climbing strategy, without special training. It is noteworthy that SAE J-185 conforms in all significant detail to ISO 2867-1980. [Contact SAE to obtain this coprighted recommended practice.]

MILSTD-1472 – U.S. military standard 1472 (current version 1472f) includes dimensional specifications for steps and handholds on vehicles and other systems. Because the military standard is publicly available, these recommendations are also widely referenced in U.S. truck design.

Summary of Recommendations from Current Standards

(See Dimensions page for dimension definitions.)

The table below summarizes the recommendations from the four standards most widely used in the U.S. SAE J185 and MILSTD 1472 specify both recommended and max/min values for most dimensions.


Standards Dimensions

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