The Department for Transport regulation is an attempt to counter the perceived threat of a terrorist attack. It comes into force on 31 July and has led to a frantic activity as firms attempt to comply.
A director at one contractor said: "The regulations are a nightmare. Some men cannot work on some sections and we are having to move workers around."
The regulations apply to all airport and port staff, including construction employees who work in restricted areas at airports or ports. The rules stipulate that an applicant for work must have at least 250 weeks' continuous employment before they can be considered for a job.
A transport department spokesman said: "Temporary staff working in restricted areas for more than five days will be required to have a temporary pass valid for 60 days." In order to obtain a pass they will have to comply with the rules governing continuous employment.
The regulations are a nightmare. We are having to move worker around Director at key airport contractor
The spokesman said the government intended to make identity requirements stricter and to scrutinise more closely people seeking to enter restricted areas at ports and airports.
Contractors at the Heathrow Terminal 5 site have had less stringent requirements imposed on them. They have been told that an applicant must have 12 months' continuous employment before they can be considered for work.
A spokesperson for airports operator BAA said the five-year rule had been waived for T5 because it was not deemed to have such restricted "airside" areas as a functioning airport with customs barriers.