406.9(B)(1) Receptacles of 15 and 20 Amperes in a Wet Location.
Code Change Summary: Revised code language recognizes other receptacle enclosures besides outlet box hoods.
NEC 406.9(B)(1) is all about specific receptacles installed in wet locations and making sure they stay dry. As well, they need to be covered in a way that the enclosure remains weatherproof whether or not the attachment plug cap is inserted. It’s quite common to see outdoor vending machines and other cord-and plug-connected equipment plugged in permanently to a receptacle exposed to rain. Using the right enclosure ensures that water doesn’t track down the cord and find its way into the receptacle.
There are many types of enclosures designed for wet locations that can keep a receptacle dry. One is an outlet box hood. Power pedestals used for RV parks and temporary construction power are another. Listed power outlets are quite common (see image).
The revised text in the 2017 NEC® makes it clear that only the outlet box hood is required to be identified as “extra-duty”. Being listed as “extra-duty” ensures that the cover is built well enough to actually stay on. Installing an outlet box hood doesn’t do much good if it’s so fragile that it breaks off after the first use.
Other listed enclosures (like in the image) that also serve to keep a receptacle dry are not required to be identified as “extra-duty”.
The revisions made to informational note 1 provide supporting language.
Below is a preview of the NEC®. See the actual NEC® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2017 NEC® edition of NFPA 70.
2014 Code Language:
406.9(B)(1) Receptacles of 15 and 20 Amperes in a Wet Location.
Receptacles of 15 and 20 amperes installed in a wet location shall have an enclosure that is weatherproof whether or not the attachment plug cap is inserted. An outlet box hood installed for this purpose shall be listed and shall be identified as “extra duty.” All 15- and 20-ampere, 125- and 250-volt nonlocking-type receptacles shall be listed weather-resistant type.
2017 Code Language:
406.9(B)(1) Receptacles of 15 and 20 Amperes in a Wet Location.
Receptacles of 15 and 20 amperes, 125 and 250 volts installed in a wet location shall have an enclosure that is weatherproof whether or not the attachment plug cap is inserted. An outlet box hood installed for this purpose shall be listed and shall be identified as “extra-duty.” Other listed products, enclosures, or assemblies providing weatherproof protection that do not utilize an outlet box hood need not be marked “extra duty.”
Informational Note No. 1: Requirements for extra-duty outlet box hoods are found in ANSI/UL 514D–2013, Cover Plates for Flush-Mounted Wiring Devices. “Extra duty” identification and requirements are not applicable to listed receptacles, faceplates, outlet boxes, enclosures, or assemblies that are identified as either being suitable for wet locations or rated as one of the outdoor enclosure–type numbers of Table 110.28 that does not utilize an outlet box hood.
Exception: 15- and 20-ampere, 125- through 250-volt receptacles installed in a wet location and subject to routine high-pressure spray washing shall be permitted to have an enclosure that is weatherproof when the attachment plug is removed.
All 15- and 20-ampere, 125- and 250-volt nonlocking-type receptacles shall be listed and so identified as the weather-resistant type.
Informational Note No. 2: The configuration of weather-resistant receptacles covered by this requirement are identified as 5-15, 5-20, 6-15, and 6-20 in ANSI/NEMA WD 6–2012, Wiring Devices — Dimensional Specifications.