Once a salvor has agreed to render salvage assistance on Lloyd’s Open Form terms, what is he basically obliged to do under the contract?

To use his best endeavours to: 

(1) salve the vessel and/or her cargo, freight, bunkers, stores and any other property thereon and take them to the place either previously or later agreed (either place to be a place of safety), or if no such place is agreed, to a place of safety; and (2) while performing the salvage services, to prevent or minimise damage to the environment.