The CITB will retest 6,000 construction workers following an investigation into CSCS card fraud prompted by a BBC exposé last month.
The organisation has closed down five internet testing centres as part of an ongoing probe after the BBC’s Newsnight revealed construction workers were paying cash to pass CSCS tests.
CITB director of delivery and customer engagement Carl Rhymer said: “While it is impossible to eliminate fraud completely, we are working hard with CSCS and the police to crack down on fraud and we are accelerating existing plans to install mandatory CCTV in all testing centres.
“We’ve also increased the number of spot checks on centres, to act as a deterrent.
“We have reviewed all test results and evidence indicates that the vast majority of the tests are legitimate.
“Following analysis of how the test was answered, using known testing patterns and geographical factors, we will require 6,000 individuals to be retested.
“Many of these are expected to be legitimate, but this is to eliminate any doubt.”
The CITB said employers do not need to take any action, unless a CSCS card has been revoked.
It has also set up a helpline for employers to contact if they are concerned: 0344 994 4053.
“All retests will be taken at centres operated by Pearson VUE,” Mr Rhymer said.
“Individuals retesting will need to register within a month and to have completed the test within three months. The CITB will issue vouchers to cover the cost of retesting.”
In 2004, Construction News reported that the Metropolitan Police had launched an investigation after forged CSCS cards were found on sites.
More recently in 2013, arrests were made in Ilford and Seven Kings in London after two men were accused of fraud relating to the CITB’s health, safety and environment test and CSCS cards.
Responses to a BBC freedom of information request showed that reports of card fraud were rising. There were 96 reports in 2012, 264 in 2013 and 311 last year, it said.
BSRIA chief executive Julia Evans said: “Construction is the UK’s most dangerous employment sector and in the past five years alone, 221 workers have died.
“As an industry, we’ve set our stall on the CSCS card being the minimum benchmark to accept workers on to our sites. This scheme has to be trusted.
“BSRIA’s members demand best practice for the industry where its workforce must be safe. This exposure is clearly unacceptable.”