
156 Mich. App. 220 (1986)
401 N.W.2d 281
PLYMOUTH FIRE FIGHTERS ASSOCIATION, LOCAL 1811, IAFF, AFL-CIO
v.
CITY OF PLYMOUTH
Docket No. 88188.
Michigan Court of Appeals.
Decided September 11, 1986.
Sachs, Nunn, Kates, Kadushin, O'Hare, Helveston & Waldman, P.C. (by Alison L. Paton), for petitioner.
Cummings, McClorey, Davis & Acho, P.C. (by Ronald G. Acho and Eileen Husband), for respondent.
*222 Before: GRIBBS, P.J., and D.E. WALSH and BEASLEY, JJ.
PER CURIAM.
Respondent City of Plymouth appeals from a decision of the Michigan Employment Relations Commission which found that the city had committed an unfair labor practice when it unilaterally subcontracted to a private agency "first response" ambulance work formerly performed by members of petitioner Plymouth Fire Fighters Association.
Prior to MERC'S October 2, 1985, decision and order, the city restored "first response" ambulance work to the Plymouth Fire Department because of problems with the private agency. Petitioner, therefore, sought to have this appeal dismissed as moot. This Court refused. A question is not moot if the action complained of will continue to affect the complaining party adversely in some collateral way. Swinehart v Secretary of State, 27 Mich App 318, 320; 183 NW2d 397 (1970), lv den 384 Mich 801 (1971). The city continues to maintain that it has no duty to bargain in good faith over subcontracting of ambulance work, and the issue may well resurface, although in a different factual context. Accordingly, we address only those issues which are likely to recur.
Section 15 of the public employment relations act requires a public employer to bargain collectively with the representatives of its employees with respect to "wages, hours, and other terms and conditions of employment." MCL 423.215; MSA 17.455(15). Subjects included in this phrase are referred to as "mandatory subjects" of bargaining. Detroit Police Officers Ass'n v Detroit, 391 Mich 44, 54; 214 NW2d 803 (1974). Neither party may take unilateral action on a "mandatory subject" of bargaining absent an impasse in negotiations. *223 Central Michigan University Faculty Ass'n v Central Michigan University, 404 Mich 268, 277; 273 NW2d 21 (1978). An employer who does so has committed an unfair labor practice. MCL 423.210(1)(e); MSA 17.455(10)(1)(e), Local 1467, International Ass'n of Firefighters, AFL-CIO v City of Portage, 134 Mich App 466, 473; 352 NW2d 284 (1984). Since public employees are forbidden to strike under PERA, Michigan courts have adopted a more liberal approach than the federal courts in determining whether a particular subject is a mandatory subject of bargaining. West Ottawa Ed Ass'n v West Ottawa Bd of Ed, 126 Mich App 306, 315; 337 NW2d 533 (1983).
Commencing in 1969, the Plymouth Fire Department, which currently is composed of six fire fighters, performed first-response emergency medical work, although this was not explicitly mentioned in the collective bargaining agreement. In 1983, nearly sixty percent of Plymouth Fire Department's total runs were first-response emergency medical runs, providing emergency first aid and transportation to hospital. When the city subcontracted this work in 1984, it did not decrease the hours of any of the fire fighters. However, when sixty percent of a bargaining unit's work has been subcontracted to a nonunion party, the decision will inevitably have an impact on the unit's wages, hours, and terms of employment.
The city argues that this decision was within its "entrepreneurial control" as part of its responsibility to insure community safety. See e.g., Local 1277, Metropolitan Council No 23, AFSCME, AFL-CIO v City of Center Line, 414 Mich 642; 327 NW2d 822 (1982). That does not alter the fact that the decision will have a significant impact on the fire fighters' employment. A requirement to bargain in good faith before subcontracting will not *224 unduly restrict the city's ability to function and to establish policy. Cf., Centerline, supra, pp 660-661.
Moreover, this Court has held that, where an employer institutes a practice not expressed in the collective bargaining agreement, the practice may constitute a term of employment which is not subject to unilateral change. Mid-Michigan Ed Ass'n v St Charles Community Schools, 150 Mich App 763; 389 NW2d 482 (1986). Where a service comprised up to sixty percent of a bargaining unit's work for over thirteen years, the employer should not be able to alter this unilaterally.
The city argues that the union expressly waived its right to claim contractual rights not incorporated in the written contract by virtue of a contractual clause acknowledging that the contact covered "the entire understanding between the City and the Union." We disagree.
We find that the contractual clause upon which plaintiff relies is not sufficiently clear to constitute a waiver of the union's right to bargain over the transfer or classification of positions outside the bargaining unit. [Lansing Fire Fighters Union, Local 421, International Ass'n of Fire Fighters, AFL-CIO v City of Lansing, 133 Mich App 56, 66; 349 NW2d 253 (1984).]
A waiver must be clear and unmistakable. Id., Mid-Michigan v St Charles, supra.
The remaining issues on appeal pertain to the circumstances in which this subcontracting controversy first developed (e.g., whether the union requested or waived bargaining and whether the city acted in good faith or negotiated to impasse). As this same set or facts is not likely to recur when the legal issue again arises, we express no opinion on those issues.
Affirmed.
