Opinion Letter

Re: Installation of Photovoltaic Systems (Solar Panels)

I write in response to your request that the Division of Occupational Safety ("DOS") confirm the job classifications, under the Massachusetts Prevailing Wage Law, for workers who perform certain tasks related to the installation of roof mounted photovoltaic systems on public works projects in Massachusetts. Your letter specifies that you are particularly interested in work performed between the dates of December 2007 and March of 2008.


The Massachusetts Prevailing Wage Law applies to the construction of public works by the commonwealth, or by a country, town, authority or district. G.L. c. 149 §§ 26 and 27. The term "construction" includes "additions and alternations of public works, including the repair and replacement of public works. See c. 149, § 27D. DOS sets prevailing wage rates established by "collective agreements or understandings in the private construction industry between organized labor and employers." c. 149 §26. DOS also looks to these agreements and understandings to determine the appropriate job classifications under the prevailing wage law. Following are the DOS job classifications of the tasks listed in your request:

  1. Construction of a Unirac ULA support structure for the photovoltaic modules: The Unirac ULA is an aluminum pipe support structure for photovoltaic modules that was constructed on the roof of the building in question.
  2. Attaching the supporting structure to the roof with bolts.
  3. Construction of a rail system with square tubing which is used to act as an angled base where the photovoltaic modules are installed.

As a preliminary matter, DOS takes this opportunity to clarify that the installation of photovoltaic modules or linking of the individual modules together to form photovoltaic arrays, including hardware is to be paid at the rate for an "Electrician" as provided on the wage sheet. This classification is established by reference to the following collective bargaining agreements: The Electrical Workers Union Local 103, IBEW Greater Boston and the Electrical Contractors Association of Greater Boston, Inc, dated September 1, 2006 to August 31, 2011; the International Brotherhood of Electrical Workers Local 7 and the National Electrical Contractors Association of Western Massachusetts Chapter, dated July 1, 2008 to June 30, 2011; and the Inside (Basic) Agreement between IBEW Local Union no. 96 and the Central Massachusetts Chapter NECA Inc., dated June 1, 2007 to May 31, 2010. As to your three specific inquiries, an examination of the applicable collective bargaining agreements and nature of the work confirms that the rate for "Electrician" applies to such work including the installation of mounting brackets and attachment of such brackets to the roof as these tasks are integral to the to the installation of the modules themselves. [1]

In addition, if portions of the roof structure are removed or re-roofed or flashing or other roofing material is required to be installed as part of the project, such work is to be paid at the rate for a "Roofer" as provided on the wage sheet. See DOS Opinion Letter PW-2008-02-04.03.08.

I hope this information is helpful. If you have any further questions, or additional information which you believe would affect the accuracy of the above determinations, please contact me at 617-626-6976.

Patricia A. DeAngelis
Acting Deputy Commissioner

[1] This determination is also consistent with the January 5, 2009 letter of the Division of Professional Licensure Board of State Examiners of Electricians to Michael P. Monahan [requiring that installation of photovoltaic modules, including hardware and mounting brackets, is required to be performed by licensed Journeymen Electricians or a properly supervised apprentice.]