Road traffic devices

Information on road traffic devices, such as breath testing, speed cameras and immobilation devices.

Breath testing devices

The guide to type approval procedures for breath alcohol screening devices used for law enforcement in Great Britain gives a description of the technical requirements which need to be met in order to be considered for type approval for police use in Great Britain. The guide contains details about the construction of breath alcohol devices, their operation and the methods of testing prior to submission to the Secretary of State for consideration.

The code of practice for preliminary impairment tests is designed for the use of police officers trained and authorised to carry out preliminary impairment tests to determine whether a person is unfit to drive and whether or not the unfitness is likely to be due to drink or drugs.

Type approvals have been divided into three categories:

1. Transport and works
2. Road traffic
3. Transport safety

The lists of these devices can be viewed on the archived version of this page maintained by The National Archives.

Drug testing devices

On 14 January 2011, we published a guide to type-approval procedures for preliminary drug testing devices used for transport law enforcement in Great Britain. The document is a reference for manufacturers wishing to develop new devices.

Manufacturers can submit devices to the Home Office for testing and if the specifications are met, the device could then be approved by the Home Secretary for use by police.

Once a screening device is approved, officers will be able to use it to test if a person has a specific level of a drug in their system and then take a blood sample if the device gives a positive reading. This will enable suspects to be dealt with quicker, cutting bureaucracy and allowing officers to get back to frontline duties. Currently, a medical examiner must be called out to assess if suspects are impaired because of drugs and authorise a blood sample.

The potential device will test for a range of drugs including cannabinoids, cocaine, amphetamines, methylamphetamine, methadone and opiates.

Manufacturers have until the end of January to indicate whether they are interested in building a screening device that meets the Home Office specification. Testing of the devices will begin in February.

Speed cameras

Evaluation of the safety camera partnerships over the four year period from April 2000 to March 2004 identified their success in reducing speeding and the resultant casualties. The evaluation found that vehicle speeds had been reduced by 70% at new fixed camera sites and by 18% at new mobile sites.

Reductions in the proportion of vehicles breaking the speed limit by 15 miles per hour or more were even greater. Both casualties and deaths were down—after allowing for the long-term trend, but without allowing for selection effects (such as regression-to-mean) there was a 22% reduction in personal.

View the complete list of speed detection devices.

On 2 February 2009, we sent a letter to the chair of the ACPO road policing enforcement technology committee to clarify the position regarding type approval of traffic law enforcement devices and the consequent admissibility in court of evidence from such devices.

Read the letter to ACPO regarding type approval and evidence.

Immobilisation devices

There are currently two approved immobilisation devices:

• LCC 'yellow triangle' wheel clamp - 2005 (no 2)
• TMP 'triangle' wheel clamp - 2005