In order to protect the contractor and the owner on account of any and all claims, damages, loss, litigation, expenses, counsel fees and compensation arising out of injuries (including death) sustained by, or alleged to have been sustained by, the servants, employees, or agents of the owner or the contractor, its subcontractors, or materialmen and from injuries (including death) sustained by, or alleged to have been sustained by the public, servants, employees, agents of the public, any or all persons on or near the work, or by any other person or property, real or personal, caused in whole or in part by the acts or omissions of the contractor, any subcontractor, materialman, or anyone directly or indirectly employed by them or any of them while engaged in the performance of this agreement, the contractor shall at all times maintain such public liability, property damage, contractor's contingent liability insurance and worker's compensation and employers' liability insurance as will protect the contractor and the owner from any and all of the above risks and from any and all claims under worker's compensation laws. Contractor shall file certified copies of all policies of insurance with the owner before commencing the work. The amount of the insurance to be provided by the contractor as provided in this agreement, together with the form of the policies and the companies in which the policies are issued, shall be subject to the approval of the owner and shall have insurance limits not less than the following: