(c) Where authority has running contracts with outside concessionaires, suppliers or others, it is necessary to have this type of endorsement included in that contractor's public liability policy:

“In the event of any accident involving personal injury or property damage or both to anyone on the premises as a result of the use, operation and delivery of the article about which the contract is drawn, that a ‘hold harmless’ agreement be given by the vendor or concessionaire to the authority and the Division of Housing indemnifying them against any and all claims as a result thereof including products.”