NEN 4400-1 is a national standard that sets requirements for temporary work businesses and contractors of work, that have their registered office in the Netherlands with respect to the payment of taxes and social insurance contributions and the legitimacy of employment in the Netherlands. The aim of the standard is to limit the risk of recovery and penalties for employers from the Dutch Tax and Customs Administration and other government agencies.

The SNA-quality assurance certification has been developed to limit risk for client and contractors. ersg is periodically checked on complying with the obligations arrived by the labor, which limits the risk for hirers and contractors.