(1) That the printing firms shall file, with the city clerk, a sworn statement to the effect that employes, in the employ of the firm or firms which are to produce the printing, are receiving the prevailing wage rate, and are working under conditions prevalent in the locality in which the work is produced.

(2) That whenever a collective bargaining agreement is in effect between an employer and employes who are represented by a responsible organization which is in no way influenced or controlled by the management, the agreement and its provisions shall be considered as conditions prevalent in said locality and shall be the minimum requirements for being adjudged a responsible bidder under this act.

(3) That in case any dispute arises as to what is the prevailing rate of wages for work applicable to the contract, which cannot be adjudged by the head of the department requiring the printing, the matter shall be referred to the city council and its decision by a majority vote thereon shall be conclusive.

(4) The words “prevailing wage rate,” as used in this act, shall be construed to mean at least the minimum wages which are received by employes of any printing firm or firms, in second class counties, as a result of collective bargaining agreements negotiated by an employer or employers with a responsible organization representing the employes. If the wage rates, so arrived at, vary in any district in such county, then any printing firm which pays wages at least equal to those provided for in any of such agreements, shall, for the purposes of this act, be deemed to be paying the prevailing wage rate.