F1 pit stop rules: what the regulations actually allow

The car is still moving when the front jack man steps into its path. He is looking at a bodywork edge rather than at the driver, judging closing speed on a machine that will stop within a few centimetres of where he expects, and he has done this often enough that the flinch has been trained out of him. Behind him, sixteen or so people are already in position, each of them holding a tool that will be in use for less than three seconds. Above the box, a camera the team was obliged to install is recording the whole thing at a frame rate that will settle any argument afterwards.

The F1 pit stop rules that govern the next few seconds are less about speed than most viewers assume. They are almost entirely about what may touch the car, who may be standing near it, how quickly it may travel afterwards, and what happens when a wheel is not properly attached. The performance is a by-product. The regulations describe a set of hazards and then constrain the working method until those hazards are small enough to accept.

Two things are worth getting straight before anything else. First, nothing in the rulebook forces a driver to stop for time or for fuel; a driver stops because the tyre regulations leave no alternative and because fresh rubber is quicker. Second, the pit lane is treated as a workplace with people in it rather than as part of the circuit, and every restriction below follows from that.

• 80Pit lane speed limit in km/h
• 1Fasteners holding each wheel to the car
• 3Safety tethers required on each wheel
• 2Dry-weather tyre specifications a driver must use in a dry race

Structural values taken from the current FIA Formula 1 Sporting and Technical Regulations. None of these are performance figures.

The tyre rule is what makes a stop compulsory at all

Nothing in the sporting regulations says a car must visit the pit lane during a race. What the regulations say instead is that unless a driver has used intermediate or wet-weather tyres at some point, that driver must use at least two different specifications of dry-weather tyre before the flag, and at least one of those has to be a specification the FIA has designated as mandatory for the race. The tyre supplier brings three dry compounds to an event and the governing body nominates, up to two weeks beforehand, which of them carry that mandatory status for Sunday.

The consequence is a stop, because a car cannot change compound while moving. A driver who runs a dry race on one specification is disqualified from the result. There is a single softening of that: if the race is suspended and never restarted, the sanction becomes thirty seconds added to the driver's elapsed time rather than removal from the classification, on the reasonable ground that the driver may have been denied the chance to comply.

Rain deletes the whole obligation. Fit an intermediate for a single lap and the requirement is satisfied, whatever happens for the rest of the afternoon. That is why a shower in the first half of a race changes a strategist's problem so completely, and it is one of the hinges that the way F1 teams build a race strategy turns on.

There is one more compound rule that catches drivers out. If a driver ends up running a set of mismatched specifications, that driver may cross the timing line no more than twice before returning to the pits to correct it, and a stop-and-go penalty follows if they do not. A mixed set is not a strategy option; it is a fault to be fixed.

The eighty kilometre limit, and the tariff for breaking it

A speed limit of 80km/h applies in the pit lane for the whole event, and the race director may amend it where the shape of a particular lane demands. That authority is used: several circuits run a lower figure because the lane is narrow, kinked, or shares a wall with a working garage frontage.

The penalty depends entirely on which session the offence happens in, and the split is instructive. In free practice, qualifying or sprint qualifying, the sanction is financial: a fine of 100 euros for every kilometre an hour above the limit, capped at 1,000 euros. It lands on the team rather than on the driver's afternoon. In the race, the stewards have a choice from the full menu of in-race sanctions, running from a five-second penalty through a ten-second penalty and a drive-through to a stop-and-go.

Underneath both sits a clause that matters more than either. If the stewards suspect a driver was speeding in order to gain an advantage rather than through inattention, they may impose a further penalty on top. That is the difference between a limiter engaged half a car length late and a limiter engaged deliberately late, and it is the reason teams treat the pit entry as a place to be scrupulous rather than a place to be brave.

A few other prohibitions live in the same article and are worth knowing because they explain otherwise baffling television moments. A car may never be reversed in the pit lane under its own power, which is why a driver who overshoots the box waits to be pushed. Cars leaving the garage may only be driven to the end of the lane, and cars queuing at the exit must go out in the order they arrived unless one of them is being unduly delayed.

When a car counts as released, and why the definition is so exact

The regulations define release with the precision of a rule that has been argued over. A car has been released from its garage when it is driven out of the garage area. A car has been released from its box after the rear axle has passed the position that the front axle occupied while the car was stationary. In plain terms, the car is released once it has moved forward by its own wheelbase.

That definition exists because everything else in this part of the rulebook keys off a single instant. Whether a car was released into the path of another, whether the wheels were on, whether the release was safe, all of it needs a moment in time that both the team and the stewards can identify from video. So the regulations go further and require each team to provide a means of establishing, when viewed both from above and from in front of the car, exactly when release happened. The reference markings you can see painted around a modern pit box are not decoration; they are the answer to a regulatory requirement.

Each team is also allocated a single pit stop camera, which it must mount directly above its box with a field of view covering the whole car while the car is stationary. It has to be uncovered and working throughout the race. A team cannot decline to film its own mistakes.

1. 1Pit entry and the limiterThe driver must be under 80km/h from the entry line, or whatever lower figure the race director has set for that circuit. Overshooting the limit in a race is worth anything from five seconds to a stop-and-go.
2. 2Approach to the boxOnly the team's own designated box may be used for a stop, and the car may not be reversed under its own power at any point in the lane.
3. 3Crew step outPersonnel may enter the lane only immediately before they are required to work, and must withdraw as soon as the work is finished. Helmets and eye protection are compulsory for anyone working on the car.
4. 4The car is liftedFront and rear jacks are operated by hand. No powered device may be used to lift any part of the car anywhere in the pit lane.
5. 5Fasteners off and onA single fastener retains each wheel. Guns may run on compressed air, nitrogen or electricity, and any sensor fitted to them may only act passively.
6. 6The release decisionThe team decides when to go. The car counts as released once its rear axle passes where the front axle was standing, and that instant is what every subsequent judgement refers back to.
7. 7Into the fast laneA car may not be released so as to endanger pit personnel or another driver, nor in a condition that is itself unsafe. Both are separate offences with separate penalties.
8. 8Pit exitThe car may only leave when the light at the end of the lane permits it, and the driver stays under the limit until the exit line.

The regulated moments in a single stop, in the order they occur. Timings are deliberately absent because the rules constrain the method rather than the duration.

Unsafe release is three offences wearing one name

Broadcast commentary tends to use unsafe release as a single label. The regulations set out three distinct wrongs, and the distinction affects who gets punished and how.

The first is releasing a car in a way that could endanger pit lane personnel or another driver, or that is likely to cause damage to another car. This is the collision case: the car going out into the path of one already travelling down the fast lane, or into the space a neighbouring crew is occupying.

The second is releasing a car in an unsafe condition. Here nobody else need be involved at all. A wheel not properly attached, a bodywork panel not secured, a fastener that has not engaged, all of these make the car itself the hazard.

The penalties diverge by session. In qualifying or any other lap-time session, the stewards may drop the driver as many grid positions as they consider appropriate, and that penalty is applied to the race unless the offence happened in sprint qualifying, in which case it lands on the sprint grid. In the race, an unsafe release brings a stop-and-go. If the release causes the driver to retire, the stewards may instead fine the team, because there is no longer a race in which to serve anything.

The third wrong belongs to the driver rather than the crew. An additional penalty will be imposed on any driver who keeps driving a car knowing it was released in an unsafe condition. A driver who feels a wheel go loose and presses on is not a victim of the team's error; the rulebook treats them as a participant in it.

Refuelling became a garage activity, and there was a reason

Fuel may be put into a Formula 1 car only in the team's own garage, never in the box, and never during the race. The regulations set a maximum transfer rate of 0.8 litres per second, allow the driver to stay in the car with the engine stopped, and require anyone handling fuel to be in clothing meeting one of the listed FIA standards, with the car and the equipment properly grounded.

Read that as a modern rule and it looks like housekeeping. Read it as the residue of an argument and it looks different. Race refuelling was outlawed after 1983 and then permitted again from 1994, which produced a decade and a half of a sport in which a stop was a fuel event first and a tyre event second. It ended after the 2009 season.

Two arguments carried the decision. One was cost, in the flat, unglamorous sense: a refuelling rig is a large piece of equipment that has to be freighted to every event, maintained, and staffed. The other was competitive. Once a car can be given a shorter fuel load, the fastest route past a rival is a lighter car and a quicker in-lap rather than a move on the circuit, and the sport had watched a generation of overtakes happen in the pit lane instead of on the track. Underneath both sat the safety case, which needs no rhetorical help: high-pressure fuel decanted next to a hot exhaust with people standing over it is a hazard that no amount of procedure entirely removes, and the era produced fires that made the point in public.

The knock-on effect is the one that shapes racing now. Cars start with the fuel they will finish with, so they begin heavy and get lighter, lap times fall through a stint for reasons that have nothing to do with the tyres, and a stop is worth only what fresh rubber is worth. That single change is why modern strategy is an argument about degradation rather than about tank capacity.

Who may stand in the pit lane, and for how long

There is no rule stating how many people may work on a car during a stop. What exists instead is a set of constraints that produce a crew size without ever naming one.

Team personnel are allowed in the pit lane only immediately before they are required to work on a car, and must withdraw as soon as that work is complete. Anyone working on a car in the box during qualifying, sprint qualifying or the race must wear a helmet meeting one of three listed standards, and eye protection is compulsory. Nobody under sixteen may be in the lane during the sensitive windows around each session unless the FIA has authorised it.

Above that sits a headcount that binds the whole operation. From twenty-nine hours before first practice until two hours after the race starts, a team may have no more than sixty operational personnel associated in any way with running the cars inside the circuit. That cap is lifted for a window running from forty-five minutes before the formation lap to fifteen minutes after the scheduled start, which is precisely the period when the grid is crowded and the crews are largest. Sixteen team members are permitted on the grid once the three-minute signal is shown, and twelve in the signalling area during a session.

The sixty-person figure is scheduled to fall in later seasons, which tells you what it is for. It is a cost control that happens to be written as a safety rule, and it is one of the levers that the F1 cost cap works alongside rather than a piece of pit lane housekeeping.

For a stop itself, the practical consequence is that a crew is sized by the job. Two people per corner for the wheel off and the wheel on, two on the jacks, one or two on the front wing adjustment, a handful of spares for the things that go wrong, and one person making the release decision. Nobody is standing there because a rule permits a particular number.

The equipment rules: no powered lift, no automation, nothing in the fast lane

Three restrictions do most of the work here, and each of them exists because of something that went wrong.

Nothing powered may be used to lift any part of a car in the pit lane. That is why the jacks are levers worked by a person who is standing directly in front of a moving car, and it is a deliberate choice: a hydraulic lift that fails with a car on it is a worse hazard than a manual one that fails with a person holding it.

Equipment may not be left in the fast lane. The lane a car travels down at the limit must be clear of trolleys, tyres and cable. Work happens in the inner lane, the strip immediately in front of the garages, and even there no work may be done that is likely to hinder another car trying to leave.

The devices used to fit and remove wheel fasteners during qualifying, sprint qualifying, the sprint and the race may be powered only by compressed air, nitrogen or electricity, and any sensor system fitted to them may act only passively. That last clause is the important one and it is easy to skim. A gun may know whether a nut has run home and may say so. It may not act on that knowledge. The decision to release remains with a human being, which is exactly where the responsibility for an unsafe release is meant to sit.

One fastener per wheel, and the device that catches it when it fails

The technical regulations are unusually specific about how a wheel is held on, and reading them tells you which failure the sport is frightened of.

Each wheel is attached with a single fastener. The outer diameter of that fastener may not exceed 105mm and its axial length may not exceed 75mm. It may not be used to mount anything to the car other than the wheel assembly, so a team cannot make the nut do a second job.

Every car, whenever it is under its own power, must carry dual-stage devices that will retain the fastener if it comes loose, both from the fully fitted position and from any partial position reached before the thread has begun to engage. That second clause is the interesting one, because it covers the cross-threaded nut that has never been tight in the first place, not just the tight nut that has worked free.

Teams have to demonstrate that those devices survive two specific tests. The retaining system must withstand 20kN of axial tensile force pulling the nut away from the centreline of the car while the nut is fully disengaged from the thread, and 300Nm of torque in the unwinding direction while the nut is partially engaged. On top of that, the system has to include a means by which the person fitting the wheel can see that a fastener is incorrectly fitted. Not infer it, not be told by a light on a gun, but see it.

Separately, each wheel carries three safety tethers built to the current FIA standard, with a combined absorbed energy of at least 15kJ and a minimum of 3kJ each. No suspension member may carry more than two of them, and every tether must have its own attachments at both ends, running from the upright to the survival cell or from the upright to the gearbox case. Those tethers exist for the accident rather than the pit stop, and they belong to a much longer argument that runs through the history of F1 safety and the halo. Their presence here is a reminder that a detached wheel is treated as one of the sport's defining hazards wherever it happens.

• 105Maximum fastener outer diameter in mm
• 75Maximum fastener axial length in mm
• 20Axial tensile force the retention device must withstand, kN
• 300Unwinding torque it must withstand, Nm

Limits and test loads set out in Article C10.9 of the current FIA Formula 1 Technical Regulations.

What actually happens in the two seconds

Strip the choreography down and a stop is four simultaneous jobs plus a decision.

The jacks go in front and behind, and both are manual. The front jack man has to be in the car's path before it has finished stopping, because a jack placed after the car settles costs time nobody has. At each corner, one person removes the fastener and the wheel and one person fits the replacement, and the wheel-off and wheel-on roles are separate because a single person cannot do both without a handover that costs more than the extra body does.

The gun operator's job is not simply to spin a nut. It is to feel the nut run home, confirm the retention device has engaged, and signal. On many teams the signal is not a shout but a switch, feeding a light that only illuminates when all four corners have reported. The person making the release decision watches that light and the fast lane at the same time, and it is the fast lane that produces the delays viewers find inexplicable, because a car held for a second and a half has usually been held for a rival travelling past at 80km/h rather than for anything wrong with the wheels.

Front wing adjustment is permitted during a stop, and the regulations restrict it to the position of the front wing profiles rather than anything structural. A car that has lost a front wing endplate needs a nose change, which is a different and much slower operation.

The reason the whole thing lands under three seconds is not that anybody moves faster than a person could a decade ago. It is that every action has been made parallel rather than sequential, and every decision that used to require a judgement has been converted into a signal. The rules push back against exactly that trend at one point only, by insisting that the sensors may not act. The sport is willing to let a stop become a machine, but not willing to let the machine decide when a car may move.

Serving a time penalty in the same box you change tyres in

A five-second or ten-second penalty is served in the team's own pit box, and the interaction with a normal stop is governed carefully.

The driver must serve the penalty the next time they enter the pit lane, with narrow exceptions for entering behind the safety car or under a red flag. While the car is stationary serving that penalty, it may not be worked on until the penalty period has elapsed, and the regulations define working broadly: touching the car or the driver with hands, tools or equipment all count. That is why you see a crew standing back with the wheels in their hands, watching a clock, and then moving as one.

A driver may also decline to serve a five or ten-second penalty at all, provided they make no further pit stop before the end of the race, in which case the relevant number of seconds is added to their elapsed time at the flag. A drive-through or a stop-and-go must be served within two crossings of the timing line from notification, cannot be served under a virtual safety car or once the safety car is out, and converts to twenty or thirty seconds respectively if imposed in the last three laps.

The stop-and-go has one further rule that reads oddly until you picture it. The car may not be worked on during the ten seconds, but if the engine stops and the driver cannot restart it unaided, the crew may act once the penalty period has run. Beyond that the car can only be worked on in the garage.

The five-minute signal and the pit lane start

Two moments outside the race apply pit stop rules in a place people do not expect them.

At the five-minute signal before the formation lap, every car on the grid and every car sitting in the fast lane must have its wheels fitted. After that signal, wheels may only be removed in the inner lane, and a stop-and-go penalty is imposed on any driver whose car did not have all four wheels fully fitted at that moment. Tyre blankets must be disconnected from power and may not be reconnected unless the start is delayed or aborted. It is a hard cut-off, and it is the reason a team that discovers a problem at four minutes will push the car down the lane rather than work on it where it stands.

A car starting from the pit lane sits in a line in the fast lane, and working there is permitted only until fifteen seconds before the formation lap begins, after which all personnel and equipment must be clear. The permitted work is a short list: starting the engine, fitting or removing cooling and heating devices, driver comfort changes, wheels and tyres, and front wing profile adjustment. No parts may be added, removed or replaced. That last sentence is what makes a pit lane start a genuine constraint rather than a free hand, and it interacts with how the starting grid is put together more often than most seasons let on.

2 km/h over200€

5 km/h over500€

9 km/h over900€

12 km/h over1000€

20 km/h over1000€

Calculated directly from the tariff in the sporting regulations, which is 100 euros for each km/h above the limit with a hard cap of 1,000 euros. Race sessions use time penalties instead and are not shown.

Show the numbers

What pit lane speeding costs a team in practice or qualifying

Item	Fine
2 km/h over	200€
5 km/h over	500€
9 km/h over	900€
12 km/h over	1000€
20 km/h over	1000€

When the pit entry is closed, and what a driver may still do

The race director can order the pit entry closed for safety, most commonly while a recovery vehicle is working near the entry road or while the lane itself is obstructed. At those times a driver may enter only for repairs that are essential and entirely evident, which is a deliberately high bar. A puncture qualifies. A tyre that has gone off does not.

The sanctions split by session again. In a lap-time session the stewards may reach for the general penalty powers, including deleting lap times or dropping the driver on the grid. In the race, a driver judged to have entered a closed pit lane for any other reason receives a stop-and-go, which is the heaviest of the in-race penalties short of disqualification. That severity is not an accident of drafting. A closed pit entry usually means there are people on foot somewhere they would not normally be, and the rule is written to remove any temptation to weigh a strategic gain against the risk of being caught.

There is a related restriction that catches teams rather than drivers. Nobody may attempt to improve the grip of the pit lane surface beyond drying it, sweeping it, or laying rubber in the ordinary course of cars leaving their boxes, and lines may not be painted on the lane. A team that wants a reference mark has to find another way to make it, which is part of why the markings around a modern box are physical fixtures rather than paint.

What to watch for during a stop

Four things will tell you more than the stopwatch does.

Watch the fast lane rather than the car. A stop that looks slow is very often a stop that was correct and held, and the giveaway is a rival passing the box a fraction before the car moves. If nothing goes past, the delay was mechanical.

Watch the front jack man's feet. If he steps aside early and the car has not moved, the crew is waiting on a corner. If the jack drops and the car sits, the release decision is being held.

Watch which corner the crew looks at afterwards. A gun operator who stays crouched by a wheel after the car has gone is telling you the retention device did not read as engaged, and that is the sequence that ends with a team calling a driver back in before the stewards do.

Watch the neighbouring box. Most unsafe release decisions involve two teams whose boxes are adjacent, because the geometry of the lane means one car's exit path crosses another crew's working space. When two cars stop within a second of each other in neighbouring boxes, the release decision has become a judgement about somebody else's mechanics.

The pit stop is the one part of a grand prix where the sport's rules are visibly about people rather than about cars, and it repays watching on those terms. More on the regulations that shape a race weekend sits in our motorsport section, and the wider run of explainers is in the blog.