Massachusetts Workers Compensation Insurance Affidavit — Building Plumbing Electrical Contractors is a form that is used to prove that a contractor has provided workers’ compensation insurance to their employees. This document is required by the Massachusetts Department of Industrial Accidents in order to protect workers in the state. This affidavit will provide proof of the contractor’s insurance coverage and will include details such as the name of the company, the amount of coverage, and the date of expiration. There are two types of Massachusetts Workers Compensation Insurance Affidavit — Building Plumbing Electrical Contractors: an initial affidavit and a renewal affidavit. The initial affidavit must be completed at the start of the contract, while the renewal affidavit must be completed annually. Both affidavits must be signed and notarized in order to be valid.