The unfettered use of DRS systems during the formative sessions of a grand prix weekend is to be more strictly controlled from next season, as the FIA announced as it revealed a handful of technical rule changes for 2013.

The change to the DRS rules has been made on safety grounds, and will see the same limitations placed on its use as currently exist in races, where drivers are only allowed to use the drag-reducing technology in specific sections of the circuit. The move appears to have been prompted by the drivers themselves, amid claims that they were not always fully in control of their cars while running through the weekend's early development phase.

"We are going to prohibit the use of DRS in practice and qualifying, except in the areas where it's going to be used in the race," FIA race director Charlie Whiting told journalists at the new Circuit of the Americas in Austin, "We believe there have been a number of incidents, and drivers have told me it is becoming increasingly prevalent, so we're doing that for safety reasons.

"One could argue that early deployment of DRS is not much different to early deployment of throttle, but the DRS is a sort of 'on-off' switch, whereas throttle can be modulated, so it's not quite the same thing. The whole point of the DRS was to ensure that we could improve overtaking in the race, but you can see now that, depending on the circuit, it can [produce] anywhere between one and one-and-a-half seconds' benefit in qualifying.

"We didn't want to have it in practice and qualifying before, but we were worried we would not have effective DRS systems," Whiting continued, referring to the belief that allowing free use of DRS in practice would lead to more effective systems and, as a result, more overtaking opportunities, "Now all the information we have is that we will not see any reduction in the power of the DRS. Teams will still use it, even though they're only allowed to use it in perhaps two places on the circuit."

As well as tweaking the DRS rules, the governing body has announced that it will also continue to tighten up on the testing of front wings, following suggestions that both Red Bull and McLaren have found ways around the current examinations.

While stronger load tests have gone a long way to eliminating flexible wings, the leading teams are now rumoured to have developed means of getting the aerodynamic pieces to rotate along their horizontal axis at speed, thereby reducing drag on the straights. To counter this, the FIA will introduce a second load during scrutineering.