HC Deb 26 January 1996 vol 270 cc461-3W
Mr. William Ross

To ask the Secretary of State for Transport if he will list for the last year for which records are available (i) the number of heavy goods vehicles over 3.5 tonnes which were given an annual inspection for road worthiness, (ii) for how many of these it was the first test, (iii) what were the 10 most common test failures by(a) numbers and (b) percentage of the total, (iv) how many vehicles failed on re-test (y) in total and (z) as a percentage, (v) how many of the failures related to braking (a) in total and (b) as a percentage and (vi) of brake failures how many were in respect of (1) service brakes, (2) secondary brakes, (3) parking brakes and (4) brake components and how many were determined (A) visually and (B) otherwise; what consideration he has give to reducing the period between tests; and if he will make a statement. [11694]

Mr. Norris

[holding answer, 25 January 1996]: The tables show:

  • Table 1 The total number of heavy goods vehicles tested in 1994–95
  • Table 2 (a) The 10 most common failure items in each category for motor vehicles
  • Table 2 (b) The 10 most common failure items in each category for trailers
  • Table 3 the number of vehicles failing retests and the percentage failure rates
  • Table 4 the total number of failures for each braking item and the percentage failure rates.

There are no plans for more frequent testing. The existing system is effective in relying on three complementary forms of control: roadworthiness testing,

Table 4: The total numbers of failures for each braking item and the percentage failure rates
Testable item Failures far braking items
Motor vehicles Trailers
Failure rate percentage Number of failures Failure rate percentage Number of failures
Trailer emergency brake Not applicable 0.042 95
Pressure/vacuum warning 0.364 1,629 Not applicable
Build up of pressure/vacuum 0.146 654 Not applicable
Hand lever operating mechanical brakes 0.033 148 Not applicable
Service brake pedal 0.052 233 Not applicable

operator licensing and its maintenance conditions; and enforcement checks carried out both at the roadside and in operators' premises.

Table 1a: The total numbers of heavy goods vehicles tested in 1994–95, (the last full year for which figures are available)
Type Total tests First and annual tests Retests
Motor vehicles 573,074 447,660 125,414
Trailers 267,443 225,648 41,795

Separate figures are not available for First Test volumes but estimated volumes are 48,000 for motor vehicles and 16,000 for trailers.

These figures are for all Heavy Goods Vehicles subject to testing under the Goods Vehicles (Plating and Testing) Regulations 1988.

Table 2a: The 10 most common failure items in each category for motor vehicles
Motor vehicles
Testable item Number failed Percentage failure rate
Headlamp aim 49,064 10.960
Service brake performance 48,450 10.823
Secondary brake performance 33,785 7.547
Parking brake performance 21,076 4.708
Braking systems components 19,921 4.450
Rear position lamps/fog lamps 19,357 4.324
Direction and hazard warning lamps 12,087 2.700
Steering linkage 7,955 1.777
Exhaust emissions 7,042 1.573
Suspension pins/bushes 7,006 1.565

Table 2b: The 10 most common.failure items for each category for trailers
Trailers
Testable item Number failed Percentage failure rate
Service brake performance 22,470 9.958
Parking brake performance 15,439 6.842
Braking system components 6,699 2.969
Rear position lamps/fog lamps 5,018 2.224
Trailer parking brake 3,112 1.379
Mechanical brake components 2,778 1.231
Suspension units (attachment) 2,306 1.022
Condition of tyres 2,207 0.978
Stop lamps 2,026 0.898
Reflectors 1,925 0.853

Table 3: The numbers of vehicles. failing retests and the percentage failure rates
Type Number of retests Number of failures Percentage failure rate
Motor vehicles 125,414 17,308 13.80
Trailers 41,795 5,668 I3.56

Table 4: The total numbers of failures for each braking item and the percentage failure rates
Testable item Failures for braking items
Motor vehicles Trailers
Failure rate percentage Number of failures Failure rate percentage Number of failures
Service brake operation 0.053 237 0.454 1,024
Hand operated brake control valves 0.177 792 0.038 86
Mechanical brake components 0.937 4,195 1.233 2,782
Brake actuators 0.624 2,793 0.768 1,733
Braking system and components 4.452 19,930 2.971 6,704
Trailer parking brake Not applicable 1.380 3,114
Service brake performance 10.822 48,446 9.958 22,470
Secondary brake performance 7.549 33,794 Not applicable 0
Parking brake performance 4.708 21,076 6.844 15,443

These figures relate to first and annual tests. Detailed figures on failures for retests are not available.

It should be noted that the figures relate to the number of vehicles failing for a particular item. In many cases vehicles will fail for more than one item.

The inspection for all items other than brake performance—(the last three items in the table—is essentially a visual inspection. The brake performance is determined with the use of a roller brake tester.