New York District Council Number 9 of the International Brotherhood of Painters and Allied Trades, AFL-CIO (Union) petitions this court to review an order of the NLRB;1 the Board cross-petitions for enforcement.2 The Board’s order provides, in relevant part, that the Union cease and desist from enforcing, unilaterally and without notice to or consultation with the charging parties herein,3 any production quota against employees of the charging parties performing work on New York City Housing Authority projects.4 The order also requires the Union to, on request, bargain collectively in good faith with the charging parties prior to enforcement of any production quota.5 We deny the Union’s petition to review; we grant the Board’s petition for enforcement.
I.
On March 5, 1968, the Union unanimously adopted at a special meeting a resolution, effective April 1, 1968, stipulating that no journeyman member employed on New York City Housing Repaint work paint more than 10 rooms per week. According to the Union, the purpose of the rule is to relieve the pressure on painters to work quickly so as to reduce the number of violations of trade rules, increase the health and safety of union members, and improve the quality of their work. The Union sought to enforce the rule by requiring members to carry cards setting forth the rule and the penalties for violation, and by instructing Union stewards to submit daily reports on production.
Prior to the announcement of this resolution, journeymen painted on average 11.5 rooms per week. The then existing collective bargaining contract made no reference to production quotas, but it did provide that Union members would work a seven-hour day, five-day work week.
*785On March 13, after receiving protests from members about the 10-room rule, Louis Elkins, secretary of the Association, informed the Union that the rule was contrary to a long-established trade principle, and that it violated Article XXII of the existing trade agreement, which provided that neither party to the agreement shall make any rule conflicting with the terms of the agreement. Elkins requested that the Union rescind the rule or refrain from taking action to implement it.
In reply Frank Schonfeld, the Union’s secretary-treasurer, contended that the rule did not violate any term of the agreement, and therefore refused to accede to Elkins’ request. Schonfeld similarly rejected a later request by Elkins that the matter be submitted to the Joint Trade Board 6 for resolution and submission to arbitration if necessary. While Elkins threatened court action, no such action was taken, apparently in the belief that the issue would be settled in the forthcoming negotiations on the new trade agreement.
Negotiations relating to a new agreement commenced in June of 1968. On July 31, the date on which the existing agreement expired, the Union called a strike, which was to last until September 9, the date on which the new contract was executed. During negotiations both sides submitted demands with respect to production quotas.7 The Association abandoned its demand early in the negotiations, but consistently refused to accept the Union’s demand. Unable to reach an accord on this issue, the parties signed the new agreement adhering to the positions they held prior to negotiations — the Association believing that the rule violated the terms of the agreement, the Union believing that the rule did not and that it was a proper means of internal union management.
As did the old agreement, the new agreement provided for a seven-hour day, five-day work week, with journeymen to be paid by the hour.
After the strike ended, the Union intensified its efforts to enforce the 10-room rule. It threatened to fine those members who did not comply with the rule. Some members, at Union urging, stopped work after painting 10 rooms even though they had not yet worked the full 35 hour week. As a result of the Union’s efforts, average production fell below the 11.5 room average.
In response, some employers discharged painters who reduced their output in observance of the rule, or docked employees for time not worked when they left the job after having met the 10-room quota.
Finally, on December 27, 1968, the five Association members and several independents filed section 8(b) (3) charges against the Union with the Board. After extensive hearings, the Trial Examiner recommended dismissal of the complaint as time-barred. The Board, one member dissenting, disregarded this recommendation, holding that the complaint was not time-barred, and that the Union had committed an unfair labor practice.8
II. The Effect of the 10-Room Rule
It is important to the resolution of the legal issues in this case to understand *786the effect of the 10-room rule. First, under the trade agreement between the Association and the Union, journeymen painters are required to work five seven-hour days a week. Second, prior to the announcement of the 10-room rule, journeymen painted on average 11.5 rooms per week. Moreover, the evidence reviewed above gives rise to the inference that but for the Union’s enforcement of the 10-room rule, journeymen painters would continue to paint on average at least more than 10 rooms per week. It is thus apparent that effective enforcement of the 10-room rule would permit those painters who can paint more than 10 rooms per week to work less than 35 hours a week.
III. Whether This Complaint Is Time-Barred
The Union first announced the 10-room rule in March of 1968; the charges giving rise to this complaint were filed in December of 1968, more than six months later. Petitioner thus contends that the complaint is time-barred by section 10(b) of the Act.9 We disagree.
The substance of the unfair labor practice charged against the Union is that it promulgated and sought to enforce a rule that violates the terms of the collective bargaining agreement between the parties. The 10-room rule is “unfair” only by reference to the terms of the collective bargaining agreement with which it allegedly conflicts. Thus, regardless of whether the announcement of the 10-room rule in March of 1968 constituted an unfair labor practice under the old collective bargaining agreement, a distinct violation occurred in September of 1968 if the 10-room rule conflicts with the terms of the new collective bargaining agreement.10 In short, even had the parties “agreed” under the old agreement that journeymen would paint 10 and only 10 rooms per week, if the terms of the new agreement are inconsistent with the 10-room rule, then by enforcing the rule the Union committed an unfair labor practice in September of 1968. If the Union committed a distinct unfair labor practice in September, then the complaint is not time-barred.
IV. Whether Enforcement of the 10-Room Rule Constitutes An Unfair Labor Practice
Section 8(b) (3) of the Act provides that it is an unfair labor practice for a labor organization to refuse to bargain collectively with an employer.11 Section 8(d), in defining the nature of the collective bargaining obligation, provides that:
. . . where there is in effect a collective-bargaining contract covering employees in an industry affecting commerce, the duty to bargain collectively shall also mean that no party to such contract shall terminate or modify such contract, unless the party desiring such termination or modification—
(1) serves a written notice upon the other party to the contract of the proposed termination or modification sixty days prior to the expiration date thereof . . .;
(2) offers to meet and confer with the other party for the purpose of negotiating a new contract or a contract containing the proposed modifications;
(3) notifies the Federal Mediation and Conciliation Service within thirty *787days after such notice of the existence of a dispute, and simultaneously therewith notifies any State or Territorial agency established to mediate and conciliate disputes within the State or Territory where the dispute occurred, provided no agreement has been reached by that time; and
(4) continues in full force and effect, without resorting to strike or lock-out, all the terms and conditions of the existing contract for a period of sixty days after such notice is given or until the expiration date of such contract, whichever occurs later. . . 12
In our opinion the Union’s enforcement of the 10-room rule violates the term of the September 9th collective bargaining agreement that stipulates that the standard work week for journeymen painters shall consist of five seven-hour days.13 By enforcing the rule the Union is in substance modifying this term to stipulate that journeymen are not to work a five day, seven-hour per day work week, but are to work only so long as it takes them to paint 10 rooms. We therefore agree with the Board that before the Union can enforce this modification of the collective bargaining agreement, it must bargain collectively with the Association over the issue. This obligation includes, of course, compliance with the four clauses of section 8(d).
The dissenting board member and the petitioner place heavy reliance upon Scofield v. NLRB14 in support of their position. We believe that this reliance is misplaced. Scofield involved charges by union members that fines imposed by their union for violation of a production quota violated their section 7 rights and therefore constituted an unfair labor practice. In holding that the imposition of the fines as a means of enforcing the production quota did not constitute an unfair labor practice, the Court was careful to point out that the imposition of the fines in no way violated the terms of the collective bargaining agreement.15 In Scofield the production quota was at a level above the production level of the average efficient worker.
We are aware that the National Labor Relations Act does not grant to the Board or to the courts the power to impose substantive contract terms upon the parties to a collective bargaining agreement.16 But the Board and the *788courts clearly have the power pursuant to section 8(d) to compel the parties to a collective bargaining agreement to abide by the terms of their agreement, and to amend those terms only through the process of collective bargaining.17 If the Union wishes to define the work week of its members in terms of their output rather than in terms of hours, then it can insist on such a provision through the process of collective bargaining.
The petition for review is denied; the cross-petition for enforcement is granted.
. Pursuant to section 10(f) of the National Labor Relations Act (Act), 29 U.S.C. § 160(f) (1970). The trade agreement between the parties terminated on July 31, 1971. We do not know whether a new agreement has been negotiated, or whether the new agreement, if any, contains a provision dealing with production quotas. However, in view of the continuing character of the obligation imposed by the Board’s order, we will examine the merits regardless of whether the case is moot. See J. I. Case Co. v. NLRB, 321 U.S. 332, 334, 64 S.Ct. 576, 88 L.Ed. 762 (1944).
. Pursuant to section 10(e) of the Act, 29 U.S.C. § 160(e) (1970).
. The eight charging parties are painting and decorating contractors. Five of the eight belong to the Association of Master Painters and Decorators of the City of New York, Inc. (Association), which represents its members in bargaining with the Union. The historical bargaining practice has been for the Union and the Association to negotiate a contract and, thereafter, for the independents to enter into substantially identical agreements with tlie Union.
. Painters District Council (Westgate Painting & Decorating Corp.), 186 N.L. R.B. No. 140, 75 L.R.R.M. 1465, 1467 (1970).
. Id.
. A board established by the trade agreement between the Union and the Association to hear complaints against either based on violations of the agreement. The board is composed of three members from each party to the agreement.
. The Union demand was that “[t]he Union shall have the right to establish a maximum standard of production.” The Association demand was a proposal to amend Article XXII to read “[d]uring the life of this Trade Agreement neither party to it shall promulgate any rules establishing a standard of production, or continue in force, or make any rules or by-laws conflicting with its provisions.” Because the Union demand was not limited to New York Housing Authority' Re-paint work, it was broader than the 10-room rule.
. See Painters District Council (Westgate Painting & Decorating Corp.), 186 N.L. R.B. No. 140, 75 L.R.R.M. 1465 (1970).
. “ . . .no complaint shall issue based upon any unfair labor practice occurring more than six months prior to the filing of the charge with the Board . . . .” Act § 10(b), 29 U.S.C. § 160(b) (1970).
. See Local Lodge No. 1424, International Assn, of Machinists’ (Bryan Mfg. Co.) v. NLRB, 362 U.S. 411, 416-417, 80 S.Ct. 822, 4 L.Ed.2d 832 (1960); Cone Mills Corp. v. NLRB, 413 F.2d 445, 448-449 (4th Cir. 1969); International Union, United Automobile, Aerospace and Agricultural Implement Workers of America, AFL-OIO v. NLRB, 124 U.S.App.D.C. 215, 363 F.2d 702, 706-707 cert, denied, 385 U.S. 973, 87 S.Ct. 510, 17 L.Ed.2d 436 (1966).
. Act § 8(b) (3), 29 U.S.C. § 158(b) (3) (1970).
. Id. § 8(d), § 158(d).
. See Associated Home Builders of the Greater East Bay, Inc. v. NLRB, 352 F.2d 745 (9th Cir. 1965). In Associated an association of builders claimed that a union’s imposition of fines upon its members for exceeding a unilaterally imposed production quota violated the union members’ section 7 rights and was therefore a section 8(b) (1) (A) unfair labor practice. The production quota imposed was at a level lower than the average production of the union members. The court found it unnecessary to decide this issue because it considered that the union’s action probably constituted a section 8(b) (3) violation. It therefore remanded the case to the Board for further findings on the 8(b) (3) issue. On remand the Board adopted the Trial Examiner’s finding that the 8(b) (3) issue was moot because the parties had subsequently executed a collective bargaining agreement that prohibited the imposition of production quotas.
. 394 U.S. 423, 89 S.Ct. 1154, 22 L.Ed. 2d 385 (1969).
. “Nor does the union ceiling itself or compliance with it by union members violate the collective contract. The company and the union have agreed to an incentive pay scale, but they have also established a guaranteed minimum or machine rate considerably below the union ceiling and defined in the contract as the rate of production of an average, efficient worker. The contract therefore leaves in the hands of the employee the option of taking full advantage of his allowances, performing only as an average employee and not reaching even the ceiling rate.” 394 U.S. at 433, 89 S.Ct. at 1160.
. H. K. Porter Co. v. NLRB, 397 U.S. 99, 90 S.Ct. 821, 25 L.Ed.2d 146 (1970); Burns International Detective Agency, Inc. v. NLRB, 441 F.2d 911, 915-916 (2d Cir. 1971), cert, granted, 404 U.S. 822, 92 S.Ct. 99, 30 L.Ed.2d 49 (1971).
. We agree with the dissent that it is not a part of the Board’s function to police the enforcement of collective agreements. But as the Court said in C & C Plywood:
. . . in this case the Board has not construed a labor agreement to determine the extent of the contractual rights which were given the union by the employer. It has not imposed its own view of what the terms and conditions of the labor agreement should be. It has done no more than merely enforce a statutory right which Congress considered necessary to allow labor and management to get on with the process of reaching fair terms and conditions of employment — -“to provide a means by which agreement may be reached.” The Board’s interpretation went only so far as was necessary to determine that the union did not agree to give up these statutory safeguards. Thus, the Board, in necessarily construing a labor agreement to decide this unfair labor practice case, has not exceeded the jurisdiction laid out for it by Congress. NLRB v. C & C Plywood Corp., 385 U.S. 421, 428, 87 S.Ct. 559, 564, 17 L.Ed.2d 486 (1967). In C & C Plywood the Court held that the NLRB did have jurisdiction to issue a cease and desist order to an employer who neither by custom nor by the terms of the collective bargaining agreement had the power to unilaterally change the wage system. See NLRB v. Strong, 393 U.S. 357, 360-361, 89 S.Ct. 541, 21 L.Ed.2d 546 (1969); NLRB v. Great Dane Trailers, Inc., 388 U.S. 26, 30, 30 n. 7, 87 S.Ct. 1792, 18 L.Ed.2d 1027 (1967); id. at 37, 87 S.Ct. 1792 (dissenting opinion of Justice Harlan); Smith v. Evening News Ass’n, 371 U.S. 195, 197-198, 83 S.Ct. 267, 9 L.Ed.2d 246 (1962); United Aircraft Corp. v. Canel Lodge No. 700, International Assn, of Machinists’ and Aerospace Workers, AFL-CIO, 436 F.2d 1, 3-4 (2d Cir. 1970), cert, denied, 402 U.S. 908, 91 S.Ct. 1381, 28 L.Ed.2d 649 (1971); NLRB v. M & M Oldsmobile, Inc., 377 F.2d 712, 715-716 (2d Cir. 1967).