Regular meetings of the commission shall be held at least once every month at such time and place as the commission shall prescribe. Special meetings of the commission shall be held upon mailed notice, or actual notice otherwise given, to each commission member upon call of the chairman or any two commission members, at such time and in such place within the district as such notice may specify, or at such other time and place with or without notice as all commission members may expressly approve. All regular and special meetings of the commission shall be open to the public, but the public shall not be entitled to any notice other than provided in this section. Unless a meeting is called for the purpose of a public hearing, members of the public shall have no right to be heard or otherwise participate in the proceedings of the meeting, except to the extent the chairman may in specific instances grant. All commission records shall be public records.