Fighting sleep while driving is the same as driving while over the limit, the Road Safety Authority warned ahead of the bank holiday weekend. Some 20,000 free cups of coffee are to be given to drivers at more than 130 Topaz garages today as part of a bank holiday "driver reviver" campaign. The RSA said that if tired drivers have a coffee and a 15-minute nap they can drive for another hour. Crashes caused by tiredness are three times more likely to be fatal or result in serious injury.