Michigan § 257.79d - "Work zone" and "temporary traffic control device" defined.

(1) "Work zone" means a portion of a street or highway open to vehicular traffic and adjacent to a barrier, berm, lane, or shoulder of a street or highway within which construction, maintenance, public utility work, reconstruction, repair, resurfacing, or surveying is being conducted by 1 or more individuals and that meets any of the following:

(a) Is between both of the following:

(i) A sign notifying the beginning of work.

(ii) An "end road work" sign or, if no sign is posted, the last temporary traffic control device before the normal flow of traffic resumes.

(b) Is between a "begin work convoy" sign and an "end work convoy" sign.

(c) If a moving or stationary vehicle or equipment exhibiting a rotating beacon or strobe light is used, is between both of the following points:

(i) A point that is 150 feet behind the rear of the vehicle or equipment or that is the point from which the beacon or strobe light is first visible on the street or highway behind the vehicle or equipment, whichever is closer to the vehicle or equipment.

(ii) A point that is 150 feet in front of the front of the vehicle or equipment or that is the point from which the beacon or strobe light is first visible on the street or highway in front of the vehicle or equipment, whichever is closer to the vehicle or equipment.

(2) As used in this section, "temporary traffic control device" means a traffic control device that is installed for a limited time period during construction, maintenance, public utility work, reconstruction, repair, resurfacing, or surveying as described in subsection (1).