Me. Rev. Stat. tit. 20-A, § 4015

When constructing a new elementary or secondary school or renovating an existing elementary or secondary school, a school administrative unit shall ensure that the school is equipped with interlocking door controller technology. The State shall provide funds to a school administrative unit to implement this section. For purposes of this section, "interlocking door controller technology" means an area in between 2 doors separating the interior of a school from the exterior and where both doors cannot be opened at the same time.