Section 8A. The governor shall appoint a board of trustees for each of the following state hospitals: Medfield, Taunton, Westborough and Worcester. A majority of the members of each such board of trustees shall be consumers and their guardians or family members. Said board shall visit and familiarize itself with its state hospital, and may from time to time make suggestions to the department as to improvements therein, especially such as will make the administration thereof more effective, economical and humane. Said board shall serve without compensation, but each member shall be reimbursed by the commonwealth for all expenses incurred in the performance of his duties.