Two separate groups of workers at Gatwick airport are to begin balloting for industrial action over pay.
If the workers vote for strike action, passengers at Gatwick are set to face delays and disruption later this summer.
Unite is conducting a ballot of over 100 members working for ICTS, who are employed to scan passengers’ luggage for explosive materials and other dangerous and prohibited materials.
The workers are paid just £8.50 an hour and are seeking an increase of 50 pence an hour.
Unite is also balloting members employed by outsourcing giants ISS.
The workers are involved in maintaining the facilities at Gatwick airport for example ensuring that toilets have the appropriate materials, as well as assisting with moving luggage and rearranging furniture.
The ISS workers are currently paid £8.49 an hour and have been forced to ballot for industrial action after management reneged on a pay offer.
The workers had agreed a two stage pay increase, with the second tranche due in April.
However, this payment was not made, the manager who arranged the original deal has left the organisation and the company has failed to honour the pay pledge.
Ballot papers for both strikes will be sent to members on Friday and the deadline for their return is July 26th.
If members vote for industrial action, then strikes could begin in mid-August, which would inevitably create disruption at the airport.
Unite regional officer, Jamie Major, said: “It is time to end poverty pay at Gatwick airport.
“The owners of Gatwick airport are making millions every year while they are allowing workers on their contracts to be paid rates below what workers can actually live on.”