SECTION 1.  Chapter 85 of the General Laws, as appearing in the 2010 Official Edition, is hereby amended by inserting, after section 21A, the following section:- Section 21B.  Notwithstanding any general or special law to the contrary, a city may establish by ordinance, on public ways under the care and custody of the city, a senior citizen safety zone, which may be an area adjacent to a facility which may be publicly or privately owned and used as senior citizen housing, a hospital, nursing home or assisted living facility, a community center, of which senior activities are conducted on a regular basis, or a congregate elderly facility approved as a planned unit development by the city.

In a senior citizen safety zone, the city may, by ordinance under the direction of the traffic engineer, take necessary action to enforce posted vehicular speed by installing signals or appropriate signs indicating the doubling of speeding fines in the designated zone. The traffic engineer may adopt and amend rules and regulations to carry out this section.

The city shall notify the state traffic engineer upon the establishment of a senior citizen safety zone. The city shall notify the state traffic engineer of any reduction of speed on a functionally-classified local roadway.

This section shall not apply to any state highway, numbered route or functionally-classified arterial.