Lorry drivers are to sit additional theory test questions from this month to meet new standards and road safety measures for professional drivers.
Haulage insurance customers will be among the new group, which also includes bus and coach drivers, required to correctly answer 85 out of 100 questions on the multiple choice element of the test.
Previously, drivers needed to answer just 51 out of 60 to earn a pass.
Jill Lewis, director of driver education and learning at the Driving Standards Agency (DSA), said: “These changes aim to further improve road safety and driving standards for professional bus, coach and lorry drivers.
“The changes represent a step change in our approach to delivering drivers to the standard needed by the road freight and passenger transport sectors.”
The test will also now be divided into two parts so that drivers can take the multiple choice and hazard perception exams at different times.
Employing 2,653 members of staff, the DSA held 1.8 million practical tests for car drivers in 2006-07, while more than 1.5 million theory tests were conducted at its centres across the UK.