RED-FACED speed camera bosses have admitted that procedures need tightening after completing an investigation into the reliability of the devices. The inquiry was launched by Suffolk SafeCam, the group responsible for the county's speed cameras, after The Evening Star revealed that a bus driver was falsely accused of hurtling through a 30mph limit at 81mph.

RED-FACED speed camera bosses have admitted that procedures need tightening after completing an investigation into the reliability of the devices.

The inquiry was launched by Suffolk SafeCam, the group responsible for the county's speed cameras, after The Evening Star revealed that a bus driver was falsely accused of hurtling through a 30mph limit at 81mph.

Trevor Martin, of Preston Drive, Ipswich, was actually travelling at 29mph when the fixed camera photographed his bus on the A140 at Earl Stonham.

The 43-year-old was able to prove his innocence as the bus he was driving was fitted with a tachograph, which recorded his speed, and a device preventing it from going above 62mph.

Terry Marsh, project manager of Suffolk SafeCam, said: "The radar uses a sophisticated targeting system over a narrow beam and if a vehicle exceeds the prosecution threshold, then the camera will be activated.

"The camera takes two pictures 0.5 seconds apart and the distance travelled in that time can be seen by examining the markings on the road.

"When staff view the film, the two photographs are compared and the recorded speed is verified by checking the distance travelled between the two photographs."

The investigation concluded that although the actual equipment had been working properly and was within the Home Office regulations, the viewing process by staff had not been properly observed.

As a result a "more robust" viewing system has now been established and secondary checks by members of staff are now double-checked.

Mr Marsh added: "The coach was recorded as having passed the camera at 81mph as a result of the targeting beam being reflected onto a second vehicle travelling in the opposite direction.

"Human error during the secondary check then resulted in the issue of the notices.

"It is important to stress that no drivers were actually prosecuted under these circumstances and as soon as the mistakes came to light the notices were cancelled and apologies issued."