Unlike other sectors, the Spanish Construction Sector has unique characteristics that make it particularly vulnerable to occupational accidents [1]. In order to solve this worrying situation, with unaffordable incidence rates for a modern and advanced economy, the Government of Spain and social agents (trade unions and construction firms) were in agreement with the enactment of Law 32/2006 [2] and its inclusion in the regulations on Occupational Risk-Prevention, to facilitate the management of subcontracting in construction works, with the aim of establishing an effective reference framework that would reduce incidence rates that devastated the Construction Sector