For the most part the regulation changes have been expected, such as moving cars' exhaust position to limit the aerodynamic effect of the exhaust gases, but others are new.

In 2012, races - including stoppages for red flags - will only be allowed to run for four hours after the rain-affected Canadian Grand Prix ran to four hours and five minutes earlier this year. Another tweak will see lapped cars allowed to unlap themselves at the end of a safety car period to ensure the race resumes in racing order. Regulations about cutting corners during in-laps in qualifying and weaving during races have also been tightened up in reaction to various incidents this season.

The FIA regulation changes in full

Changes to the 2012 Technical Regulations

• All engine standard ECU set up and control parameters, which were formerly contained only within a Technical Directive, are now contained within the relevant parts of the Technical Regulations.
• The exhaust tailpipes are now strictly regulated in order to ensure that the aerodynamic effect exhaust gases have on the car is kept to an absolute minimum.
• Better marking of in-car emergency switches operated by marshals are now stipulated.
• The side impact structures will now have to be subjected to a further (upward) push-off test.

Changes to the 2012 Sporting Regulations

• Cars may no longer take part in pre-season testing without having passed all crash tests.
• There will now be a maximum race time of four hours to ensure that a lengthy suspension of a race does not result in a race that could run up to eight hours if left unregulated.
• Before the safety car returns to the pits all lapped cars will be allowed to unlap themselves and then join the back of the pack, ensuring a clean re-start without slower cars impeding those racing for the leading positions.
• Cars which were in the pit lane when a race is suspended will now be allowed to re-join the cars on the grid in the position they were in when the race was suspended.
• Drivers may no longer leave the track without a justifiable reason, i.e. cutting a chicane on reconnaissance laps or 'in' laps to save time and fuel.
• Drivers may no longer move back onto the racing line having moved off it to defend a position.
• One three-day test will be carried out during the season, formerly there were none.
• All stewards' decisions which are not subject to appeal are now in one place instead of being in various places within the regulations.
• All tyres allocated to a driver may now be used on the first day of practice; formerly only three sets were permitted.

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