How citations work here
Primary law comes first. Where a rule is set by a statute, a standard, or a regulation, we cite that source directly rather than a secondary description of it. Every fact on a requirement page shows the exact section it comes from and a link to the source, and every page is dated so you can weigh how current it is. When a federal baseline and a state rule differ, we show both and note which applies.
Source families
MUTCD, 11th Edition
The federal Manual on Uniform Traffic Control Devices. The standard for signs, markings, and temporary traffic control and work zones.
2010 ADA Standards
Standards for Accessible Design, including accessible parking counts and the dimensions for stalls, access aisles, and signage.
23 CFR
Federal highway regulations, including the rules that give the MUTCD legal force on public roads.
OSHA 29 CFR 1926 and 1910
Federal worker-protection regulations for construction and general industry, including work-zone and high-visibility requirements.
ANSI/ISEA 107
The consensus standard for high-visibility safety apparel, defining the performance classes for garments worn in the right-of-way.
MASH and NCHRP-350
Crashworthiness criteria for roadside and work-zone hardware, including sign supports, barriers, and attenuators.
State statutes and administrative codes
State laws and agency rules that add to or vary from the federal baseline, such as accessible-parking dimensions or work-zone provisions.
State DOT standards
State transportation department plans and manuals, such as the FDOT Standard Plans and the Texas MUTCD, that govern practice in that state.
For a plain-English overview of the major standards, see standards. To understand how we check each fact against these sources before publishing, see how we verify.
Informational only, not legal advice. Always confirm against the current edition of each standard and your state manual.