“NEMA OS 4 provides the outlet box industry a much-needed and standardized set of metrics. It gives building designers assurance that boxes made to this standard will provide the design features needed to effectively seal air barrier penetrations in order to comply with building and green energy codes,” according to David Kendall, chair of the NEMA Outlet and Switch Box Section. “Our industry anticipates that these boxes will also reduce potentially undesirable effects from using unspecified sealing techniques.”
NEMA OS 4-2016 is the first industry standard dedicated to testing electrical outlet boxes for their performance in maximizing energy efficiency in building structures, according to the organization. It is available for $60US in hard copy and as an electronic download on the NEMA website.