ANSI/ISEA 107 is the standard. It splits hi-vis garments into three classes based on how much fluorescent and reflective material they have, and where it's placed.
Class 1 is the lightest. Minimum fluorescent area, minimum reflective tape. It's for off-road use only — warehouse workers, parking lot attendants, anyone working away from public traffic. If a vehicle is moving past you faster than about 25 mph, Class 1 isn't enough.
Class 2 is the workhorse. More fluorescent fabric, more reflective tape, the tape arranged so the wearer reads as a human shape from a distance — head, torso, arms. Class 2 covers public roadways with traffic up to about 50 mph. Most road crews, utility workers, surveyors, and parking enforcement wear Class 2.
Class 3 is the highest. Full sleeves required, fluorescent material on the arms, reflective bands that wrap arms and legs so motion is visible. Class 3 is for high-speed traffic — interstate work, night work, low-light conditions. If you're a flagger on a highway shoulder at 2 a.m., you're in Class 3, full stop.
There's also Class E — for pants and bibs that, when worn with a Class 2 or 3 top, satisfy the high-visibility requirement. A Class E pant by itself is not sufficient.
Couple things people get wrong. The class is about the garment, not the color. Both safety yellow (lime) and safety orange satisfy the standard. Pick the one that contrasts best with your work environment — yellow stands out against asphalt and dirt, orange stands out against green vegetation and snow.
Reflective tape needs to be 360 degrees visible. A Class 2 vest with the tape only on the front isn't a Class 2 vest. Look at the back. The tape should make a continuous loop or an X.
Wash your hi-vis. Dirt and grease kill fluorescence — the bright color is doing half the work in daylight, and a dirty vest reads as gray-green from 200 feet away. Most ANSI vests are rated for 25 wash cycles before they fall out of spec. After that, replace it.
We stock Class 2 and Class 3 from a few brands, plus FR-rated hi-vis for utility and oilfield work. Bring your job spec or tell us your trade — we'll get you to the right class.