RMC WILL ban contractors from visiting its quarries and Readymix sites from next April unless they carry industry safety passports.
Chief operating officer Mike Ogden announced the decision, which will affect the 1,500 firms who regularly visit RMC sites every year, this week.
Mr Ogden said: 'It is time to make a stand.We are drawing a line in the sand and stating our position quite clearly.We believe we are the first in the industry to make this commitment. Safety for our contractors and employees is not an option, it is a must.'
The passport scheme was introduced three years ago by the Quarry Products Association.
Mr Ogden said: 'There are over 8,000 contractors in the UK and approximately 50 per cent already have a safety passport.
'We want to continue to guarantee good practice. If contractors and suppliers want to work with us and haven't got a passport, they must apply now.'
To gain a passport contractors have to take an accredited two-day course.
Mr Ogden said the April 1 deadline included a three-month grace period to attend courses and the majority of firms would be expected to have documents by January 1, 2005.