Race tracks that host international competitions are often given grades that are designed to reflect the level of competition this track can hold—but the qualifications can often be pretty murky. That’s why, today, we’re going to be delving into the FIA track grading system so that it makes more sense.

Most race fans have probably heard of track grading as it pertains to why one certain track can or cannot host a Formula One race, but the grading system goes a lot deeper than that. And it’s worth a quick exploration by race fans.

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Basically, grading tracks is a way to determine the type of cars that can safely race on a track. These events are sanctioned by the Fédération Internationale de l’Automobile (FIA), so the standards are fairly high. That’s why Formula One can’t race on all the American tracks that IndyCar races on—F1 requires a much higher level of safety, maintenance, fan accessibility, and facilities.

That derives from F1's long term push for a higher level of safety to coincide with its high-dollar technical development. If you’re spending that much money and marketing yourself as the pinnacle of motorsport, having dangerous circuits kind of goes against the whole ethos of both F1 and the FIA; it just shows you didn’t do a good enough job doing the thing you claim to do better than everyone else.

So, there’s an incentive to regulate the standards of tracks, which the FIA generally does via a power-to-weight ratio. That means that super-powerful and super-light cars need specific track features to keep them both safe and to make for better racing (but that last point is debatable, depending on who you ask). Track standards also take into account the other track facilities, like ADA-accessible bathrooms and medical center staffing due to the potentially larger crowds the series can draw and the type of accidents that are most common for a certain series.

In essence, a well-graded track is an assurance that the drivers will be safe and the fans will have an appropriately good time.

Can host

Group D and E cars with a weight/power ratio of less than 1kg/hpHistoric cars, including post-1985 F1 carsBasically: Formula One

Examples

Anything F1 competes on

Can host

Private testing of previous F1 cars

Can host

Group D and E cars with a weight/power ratio of 1-2 kg/hpThat includes some historic carsJunior single-seater racing like Formula 2, some Grand Touring cars

Examples

Barber Motorsports Park (and most IndyCar road/street circuits), Circuit de la Sarthe, Donington Park

Can host

Category II cars with a weight/power ratio of 2-3 kg/hpSome historic carsJunior single-seaters like Formula 3

Examples

Most Formula E street circuits, Pau, Mount Panorama, Oulton Park

Can host

Electric cars with a weight/power ratio of 2-3 kg/hp

Examples

Other Formula E street circuits, like Riyadh, Berlin, Sanya, Diriyah, and Santiago

Can host

Category I cars, plus Category II cars with a weight/power ratio of over 3 kg/hpSome historic cars that don’t meet regulations from previous grades

Examples

Goodwood,

Can host

Alternative-energy vehicles

Can host

Autocross

Examples

Autocross Nová Paka, Seelow Autocross Circuit

Can host

Rallycross

Examples

Trois-Rivières, Circuit of the Americas’ rallycross course

Can host

Ice racing

The FIA spends most of its time detailing the mandatory requirements for permanent circuits of Grade 1 to 4, adding on special dispensations for certain series, like F1 or WEC. And these rules are complex. Appendix H of the FIA’s international sporting code spends 134 pages outlining every single requirement, which can range from the width of the track to the type of medicine that has to be included in the medical center. But some of the big ones for Grade 1 tracks include:

. Straights can’t be longer than 1.25 miles, and tracks must be at least 2.18 miles long (with the exception of Monaco). Tracks are not recommended to be longer than 4.35 miles. Permanent tracks must be at least 40 feet wide, but temporary tracks like Monaco may be narrower. And then there are regulations for things like grid spot spacing, banking, pitlane width, and more.. There are certain requirements for barriers and run-off zones depending on the layout of the track. There aren’t really set rules, but it’s probably a smart idea to follow the FIA’s suggestions of including some combination of grass, sealed surface run-off areas, curbs, deceleration beds, stopping barriers, and energy-absorbing barriers. There are some serious requirements for medical centers. They have to be permanent for all Grade 1-4 tracks, and for higher-level events, there must be two doctors present who are proficient in resuscitation, plus two surgeons, one of whom must be trained in the initial treatment of burns and the other that has to manage spinal injuries and concussions. The medical team needs to be able to speak English and deal with trauma. And there needs to be a whole host of medical technology: ventilators, heart-rate monitors, oxygen reserves, x-rays, ultrasound equipment, and more.

Among countless other things. There are formulae for determining the number of cars allowed on track during a specific event, and there are requirements for the advertisements that line the circuits. There are regulations for fans and regulations for drivers. Basically, developing and subsequently maintaining a Grade 1 circuit is an expensive, time-consuming job, which is why there are currently only 37 circuits that can host F1 events. You have to really want that license.

But it’s also not super easy to figure out what, exactly, goes into designing a specific grade of circuit unless you’re really serious about it. Which generally means you have money. Which is generally the best way to get the FIA to notice you in general.