Thatcham Explained

Thieves are becoming increasingly technologically aware in the methods they adopt to steal vehicles. Because of this, security systems have to do more than just sound a loud alarm.

In 1993 the Motor Insurance Repair Research Centre (MIRRC) at Thatcham in Berkshire was tasked with establishing standards for car security systems - testing, evaluating and approving them as able to meet the demands required by insurance companies. The result was the Thatcham set of criteria, rigorous product testing standards and lists of approved products, reviewed regularly. Thatcham gives Category numbers to each section of the security market:

The Thatcham Vehicle Security Categories

Thatcham have defined a number of categories for vehicle security devices and produced criteria and test specifications for each category. The list below shows what these categories cover and the principal features required.

Category 1
Passenger Cars, LCV, HGV, Plant, Motorcycles
ELECTRONIC ALARM AND IMMOBILISER

• Alarm
  Perimeter detection
  Ignition detection
  Passenger compartment movement detection OR glass break and inclination detection
  Audible warning with battery back-up power supply
• Immobiliser
  Passively set
  Isolates a minimum of two operating circuits or systems, or a minimum of one operationally relevant vehicle control unit with coded intervention

Category 2
Passenger Cars, LCV, HGV, Plant, Motorcycles
ELECTRONIC/ELECTROMECHANICAL IMMOBILISER

• Immobiliser
  Passively set
  Isolates a minimum of two operating circuits or systems, or a minimum of one operationally relevant vehicle control unit with coded intervention

Category 2/1
Passenger Cars, LCV, HGV, Plant, Motorcycles
ELECTRONIC ALARM UPGRADE [GENERAL APPLICATION]

• Alarm
  Perimeter detection
  Ignition detection
  Passenger compartment movement detection OR glass break and inclination detection
  Audible warning with battery back-up power supply
  Resistance to attack for a minimum of one minute
  Installed on vehicles with existing Category 2 immobilisation to attain Category 1 status

Category 3
Passenger Cars, LCV, HGV, Plant, Motorcycles
MECHANICAL IMMOBILISER

• Immobiliser
  Easy to set and unset
  Isolates a minimum of one operating system
  Permanently or temporarily installed

Category 4
Passenger Cars, LCV, HGV, Plant, Motorcycles
WHEEL LOCKING DEVICES

• Reliability and durability
• Secure key replacement procedure
• Product traceability
• Resistance to attack

Category 5
Passenger Cars, LCV, HGV, Plant, Motorcycles
AFTER THEFT TRACKING AND RECOVERY SYSTEMS

• Vehicle location systems
• Vehicle remote immobilisation systems
• Vehicle signalling systems

Q Class Systems
Passenger Cars, LCV, HGV, Plant, Motorcycles
AFTERMARKET ‘NON CATEGORISED’ SYSTEMS

• Alternative alarm systems
• Vehicle marking systems
• Vehicle data recording systems
• Vehicle paging systems
• Vehicle location systems
• Vehicle ID systems
• Vehicle signalling systems
• Uprated door lock devices
• Image recorders