Gem Bids For Ration And Maintenance Of Electro-mechanical Installations, Operation And Maintenance Of Fire Alarm System, Repair, Maintenance, And Installation Of Plant/ Systems/equipments (version 2), Hiring Of Boats, Operation And Maintenance Of Substation, Operation And Maintenance Of Lifts (elevators), Refilling Of Industrial Gases In Cylinders, Annual Maintenance Service-air Conditioner, Annual Maintenance Service For Centralised Air Conditioning System, Operation And Maintenance Services Of Power Generator(dg-set)