The change was first proposed in January when a consultation was launched about toughening the regulations surrounding track limits.
Instead of the existing rule of an offence being committed if "any wheel of the car goes completely beyond" white lines or the edge of a kerb, it was suggested the definition should change to be "any part of the contact patch of the tyre goes beyond either the outer edge of any kerb or the white line where there is no kerb".
This has now been approved by the Motorsport UK board and will be effective from next weekend.
However, plans to significantly alter the penalty system – including introducing a one-second time addition for the first offence – have been dropped following the consultation.
Motorsport UK CEO Hugh Chambers has written to all race licence holders on Thursday explaining the new rule and the reasoning behind making the change.
As part of the letter, Chambers said that the rule tweak has arisen following a wider review of driving standards and a belief "there is less than a universal understanding of where the limit of the track lies".
"The track limit is there for very good reasons, safety and fairness," he added.
"In regard to safety, the track licence that is provided by Motorsport UK considers all of the safety measures in place at a track and in particular the run-off areas on any part of the circuit including the physical interventions that are in place to minimise any impact.
"Without track limits regulations and enforcement, the circuit owners are in an impossible situation.
"In the interests of minimising damage to vehicles, the governing bodies of both car and bike racing have reduced permissible physical deterrents to going beyond track limits – and the circuits understand this.
Motorsport UK has endorsed new rules
Photo by: Porsche
"But, without any deterrents, the grass and earth beyond the kerbs just gets abused and deeply rutted in no time.
"This simply cannot be repaired fast enough and presents a real physical hazard for any vehicle that leaves the track through incident or error.
"It is therefore imperative that vehicles should be contained within the limits of the track in order to conform to those precise safety measures that have been installed.
"In addition to safety, the limits of the track are there to ensure that racing is fair and that all the competitors compete by lapping as swiftly as possible on the same pieces of Tarmac."
Chambers therefore believes changing the rules to make drivers who even put part of a wheel beyond the kerb or white line an offence "will make it simpler for everyone".
He also addressed the difficulty in policing the new regulation, saying this has long been a problem.
"There is certainly scope for increasing use of technology to be developed, but as even F1’s continuing issues demonstrate, it is not easy," he said.
"The cost of installing and particularly maintaining and operating track limits technology is significant, and race entry fees would likely increase if all circuits had complete coverage – which, quite naturally, we all want to resist.
"Motorsport UK is committed to work with the circuit owners and together develop affordable track limits technology, but this will take time.
Motorsport UK acknowledges that policing the new rule will bring challenges
Photo by: JEP / Motorsport Images
"In the absence of track limit sensors, the reporting of breaches is conducted by judges of fact, appointed by the organiser, and who report breaches to race control.
"As with any sporting decision by an official or referee, there is the opportunity for human error, and it will not be universally accurate, inexactly the way it has been until now.
"However, the change from 1 June is designed to make it easier to spot transgressions, nevertheless the reality is that no system will be entirely capable of penalising every breach.
"Whilst it is true to say that this does present challenges both for the observers and the officials, it does not undermine the principle that we need to have a clear rule.
"There are many instances in life where laws are in place but do not have universal capture, but the deterrent is there nonetheless, and the majority conform."
The new rule has already been adopted by the British Touring Car Championship and its support categories to ensure consistency throughout the season, while British GT also decided to introduce it early from the Silverstone round at the start of the month.2023-05-25T14:09:36Z dg43tfdfdgfd