10,000 Haulage Firms on Safety 'Red List'
About 10,000 haulage operators are on a "red list" because of the risk they pose to other road users, the body that enforces lorry safety in Britain says.
The list represents one in eight transport firms, and is used by the Driver and Vehicle Standards Agency to target enforcement.
The hauliers are failing to ensure adequate maintenance and safety, or to monitor drivers' hours, the DVSA says.
But it said sanctions for repeatedly flouting the rules are inadequate.
DVSA chief executive Gareth Llewellyn told the BBC the regulatory system was "ripe for review".
Transport firms with vehicles weighing 3.5 tonnes or more need an operator licence, which carries obligations to ensure vehicles are roadworthy, safely operated and regularly inspected.
The DVSA enforces the regulations through roadside spot checks. In 2015/16, just over 29,000 HGVs were checked at the roadside or at operators' premises, and nearly 9,000 were served with prohibition notices.
Depending on the severity of the defect, a vehicle is immobilised until repaired or the operator is given a deadline to get it fixed.
The agency scores operators on the likelihood their vehicles will be operating safely, with a green, amber or red rating.
Mr Llewellyn said: "Where we believe there is something of imminent impact for the public, we will impound that vehicle - it is about making sure those things that are really posing a risk to the public are taken out very quickly."