§ 402. Application. The rules and procedures for display and use of the flag set forth in this article shall govern the display of the flag on all public buildings within the state and shall supersede any contrary rule or custom of state or local agencies governing display provided, however, a school district may promulgate its own regulations to allow the flag to be flown at half-staff to commemorate the death of a present or former board member, present employee, teacher, student, clerk or custodian.