How we verify

Every fact traces to primary law

We do not paraphrase a blog or repeat a vendor spec sheet. Each requirement we publish is anchored to a primary source: the MUTCD, the 2010 ADA Standards, an OSHA regulation, a section of 23 CFR, or a state statute, administrative code, or DOT standard. If a claim cannot be tied to that kind of source, it does not go on the page.

Every requirement carries a quote, a section, and a link

Each record shows three things you can check yourself:

• A verbatim quote from the source, so you can read the exact language the rule comes from.
• The exact section or citation, so you know precisely where it lives in the source.
• A link to the source, so you can open it and confirm without taking our word for it.

You should not have to take a number on faith. The evidence sits next to the claim, so you can confirm it in a few clicks.

Records are dated

Standards change. Editions are revised, states adopt new manuals, and thresholds move. Every published record shows a last-verified date so you can judge how current it is, and we re-check records over time rather than treating a fact as settled forever.

A human reviews before anything is published

Draft requirements are never published automatically. A person reads each draft against the quoted source and publishes only what checks out. Anything that does not match stays as a draft and never reaches a public page.

Readers can flag errors

Every requirement page includes a Report an error control. If you spot something that looks wrong or out of date, you can flag it directly, and it goes into the review queue for that record. Reader corrections are one of the main ways an entry gets fixed after it is published.

For the step-by-step build process behind this, see our methodology. For the primary sources we rely on and how citations work, see sources and citations.