The definitive answer;
If a mobile camera van takes a photograph at a distance greater that the calibrated distance stated on the camera partnership website for the equipment, is it enforceable? I was snapped allegedly doing 41mph in a 30mph zone at a distance of 220m, but the certificate for the model of camera seems to only prove a 100% accuracy to 80m distance. This is particularly relevant as up to 39mph I could have simply opted for the naughty chap lecture and received no points. There were also no speed enforcement signs on the road concerned or for that matter any speed limits signage. Are they required to put these in place before operating their trap? The camera used was a LTi20-20 TS/M SpeedScope Speed Measuring Device.
The camera sign is a recommendation not a requirement.
This device has type approval to 999.99m.
Below is more than you ever wanted to know about the LTI 20.20 “Speedscope†laser speed measuring equipment.
LTI 20.20 “Speedscope†laser speed measuring equipment is required by the Secretary of State as with all such devices, to be Type Approved for enforcement use. The appropriate approvals in respect of the LTI 20.20 “Speedscope†are The Road Traffic Offenders (Prescribed Devices) Order 1993 and the Light Beam Speed Measuring Device Approval 1996. The latter came in to force on 1st April, 1996 and relates specifically to the LTI 20.20 “Speedscopeâ€
To acquire such a Type Approval, equipment needs to be independently tested to extremely high standards of measuring accuracy and assessed for the effects of interference from Radio frequency and Electromagnetic fields.
It also needs to meet high standards in environmental factors such as extreme heat and cold and waterproofing.
It is Type Approved for use within the measurement ranges specified by the Manufacturer as 0 – 999.9 metres and 0 – 299 mph
The LTI 20.20 “Speedscope†has a speed measuring accuracy within +/- 1mph. Because it operates on laser light frequencies it is unaffected by Radio frequency and Electromagnetic fields.
It also meets all the standards in respect of the environmental factors.
The device uses as its measuring medium a beam of infrared laser light which has been approved to Class One laser standards and presents no health hazards.
The 3-milliradian beam, which has a maximum range of in excess of 1 kilometre in the United Kingdom version, has a width of approximately 1.2 metres at a range of 400 metres and is thus narrow and precise. At that range, however, the ‘active’ portion of the beam is somewhat smaller. The calculations carried out by the equipment uses the speed of light as the constant value