MSHA - Code of Federal Regulations - 30 CFR 56.11002
Mine Safety and Health Administration
    MSHA - Protecting Miners' Safety and Health Since 1978

MSHA - Title 30 CFR
30 CFR § 56.11002
Handrails and toeboards.
Crossovers, elevated walkways, elevated ramps, and stairways shall be of substantial construction provided with handrails, and maintained in good condition. Where necessary, toeboards shall be provided.