29 CFR § 1.7 - Scope of consideration.
(a) In making a wage determination, the “area” from which wage data will be drawn will normally be the county unless sufficient current wage data (data on wages paid on current projects or, where necessary, projects under construction no more than 1 year prior to the beginning of the survey or the request for a wage determination, as appropriate) is unavailable to make a wage determination.
(b) If sufficient current wage data is not available from projects within the county to make a wage determination, wages paid on similar construction in surrounding counties may be considered.
(c) If sufficient current wage data is not available in surrounding counties, the Administrator may consider wage data from similar construction in comparable counties or groups of counties in the State, and, if necessary, overall statewide data.
(d) If sufficient current statewide wage data is not available, wages paid on projects completed more than 1 year prior to the beginning of the survey or the request for a wage determination, as appropriate, may be considered.
(e) The use of “helpers and apprentices” is permitted in accordance with part 5 of this subtitle.