SPEED cameras are to be deployed on the Forth Road Bridge during roadworks and could become a permanent feature to cut crashes and congestion.
A reduction in the crossing's speed limit from 50mph to 40mph may also be considered.
Average-speed cameras, which measure vehicle speeds over set distances, will be used to enforce a 30mph restriction during work starting in 2009 or 2010.
But
Tony Martin, the leader of the Forth Estuary Transport Authority (Feta), which runs the bridge, said such equipment should be kept to improve traffic flow by keeping speeds down.
He said lorry speeds appeared to have increased since the abolition of tolls two weeks ago because drivers no longer had to stop before crossing.
Average-speed cameras have dramatically reduced speeding and crashes on the A77 in Ayrshire and at several roadworks sites across Scotland. But some drivers' groups opposed permanent installations on the bridge and called for its 50mph speed limit to be increased instead.
Feta is planning to use average-speed cameras when 7ft-high ramps are installed for the replacement of worn-out carriageway expansion joints.
The work will take place on each carriageway in consecutive years, with ramps installed above the two joints, beside each of the bridge's main towers.
The 30mph limit is needed because the ramps will make vehicles more prone to winds, which funnel round the towers.
Officials are anxious drivers do not accelerate then brake sharply between the two 300ft-long ramps, causing a ripple effect that slows traffic.
Mr Martin said: "The cameras will be temporary, but it is a good way of trialling the system to see if it works and whether we could do it over the whole bridge.
"People are very suspicious of cameras, but on a structure like this, safety is so important that drivers have to keep their speeds down. Any incident causes massive traffic disruption."
The Feta convener added that cutting the bridge's speed limit by 10mph to improve traffic flow should also be examined, following its success on the M25 around London. He said: "It is something we should keep under review."
Neil Greig, of the Institute of Advanced Motorists' Motoring Trust, said any permanent speed curbs should be aimed at lorries. He said: "There is no doubt lorries do most of the damage to the bridge. Until we get a new bridge, we will need such technology to keep traffic flowing."
However, Bruce Young, of the Association of British Drivers, said: "I can see no merit in permanent cameras, and the speed limit should be raised to 70mph. Studies in the United States have shown that raising speeds makes drivers space apart better and improves the flow."
