CONTRACT workers are threatening a hospital with strike action if a long-running pay row is not resolved.

Portering, catering and cleaning staff at Darent Valley Hospital are voting on whether to take industrial action on March 25, the day of Dartford and Gravesham NHS Trust’s board meeting.

Public services union Unison has campaigned on behalf of 243 workers employed by private contractor Carillion to get the same rates of pay for working unsocial hours as NHS staff.

Carillion, which is paid by the trust to run non-clinical services, agreed to pay the same rates and offered to backdate payments to April 1 2009, the start of this financial year.

However the union wants payments to be backdated to October 2006, when a pay deal was announced to bring their wages in line with NHS staff.

If pay was to be backdated some workers could be owed as much as £3,500.

Unison’s regional organiser Zoe Van Dyke said: “We recognise there may be an affordability issue at the present time but they could work out some sort of phased payment scheme even if it was over five years.

“Our members see it as a debt to them.”

The union was planning to strike last Christmas but it decided to wait until its membership had increased.

Mrs Van Dyke said: “Member numbers weren’t high enough to believe we would have a significant impact.

“Since then people have been joining us in droves and we have more than doubled in membership because people want us to act on their behalf.”

She added: “Portering, catering and cleaning staff are health service workers in the same way nurses and doctors are.

“Without any of these staff the hospital would not run.”

Unison expects to know on March 17 whether or not a strike will go ahead.

A trust spokesman said: “Unison’s dispute is with their member’s employer, Carillion.

“We are of course disappointed that Unison is balloting for strike action and hope this can be avoided.

“In the event of a strike we will be working closely with Carillion to ensure that normal services are maintained.”

Carillion has been asked to comment.