Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 90, § 16B

(a) For the purposes of this section, the term “school grounds” shall mean in, on or within 100 feet of the real property comprising a public or private accredited preschool, accredited Head Start facility, elementary, vocational or secondary school whether or not in session, and shall include any athletic field or facility and any playground used for school purposes or functions which are owned by a municipality or school district, regardless of proximity to a school building, as well as any parking lot appurtenant to such school, athletic field, facility or playground.

(b) No person shall cause, suffer, allow or permit the prolonged idling of a motor vehicle engine on school property in violation of registry of motor vehicles regulations relative thereto, adopted pursuant to subsection (c). An operator or owner of a motor vehicle who violates this section shall be subject to a civil assessment of $100 for the first violation and $500 for a second or subsequent violation. This subsection shall be enforced by law enforcement agencies.

(c) The registrar of motor vehicles, in consultation with the department of education, the department of environmental protection, the executive office of public safety and the executive office of health and human services, shall adopt regulations to implement this section. Such regulations shall include, but not be limited to, establishing the length of time an operator on school grounds may idle an engine before such idling becomes prolonged, and the limited circumstances under which the prolonged idling of an engine shall be permitted, including periods necessary to operate defrosting, heating or cooling equipment to ensure the health or safety of a driver or passengers or to operate auxiliary equipment and to undergo inspection or during maintenance. Such regulations shall prohibit an operator of a school bus from idling a school bus engine while waiting for children to board or exit a bus on school grounds and from starting a school bus engine for any unnecessary period of time in advance of leaving the school grounds, unless the registrar determines that a school bus engine must be fully engaged in order to operate safety devices or that such idling prohibition would otherwise compromise the safety of children boarding or exiting a bus. Such regulations shall further prescribe templates for “no idling” signage to be posted by schools.

(d) The registry of motor vehicles shall notify all individuals certified and endorsed to be school bus drivers of the provisions of this section and regulations adopted pursuant thereto during the annual certification process required by this chapter.