Work Surface

NFPA 70-2023 introduced a new term to Article 100 to add clarity to a term that was introduced during the 2020 cycle in 210.52.  This new definition tells the user of the code that a work surface is a fixed, stationary, or portable surface typically intended for dry use and for tasks other than food preparation, personal lavation, or laundering. These are those applications that present an incidental risk of spillage of smaller quantities of beverages and other liquids.  The concern here is for those work surfaces that employ outlets mounted directly on or recessed in the surface.  There are two informational notes that are provided referencing UL 111, “Outline of Investigation for Multioutlet Assemblies”, and UL 962A, “Furniture Power Distribution Units”.  These standards, together with UL 498 have what are called “Spill Tests” and help establish the performance requirements for receptacles installed in these types of applications that are exposed to liquid spills.

The challenge is in the recognition of what is a work surface and what is a counter/countertop. 

More information can be found in 406.5(F), 406.5(G)(1), and 406.5(H).  These specific sections of the Code provide information on receptacles for work surfaces distinguished from receptacles for counters and countertops.

There is also a definition of “work surface” that can be found in UL 111, “Outline of Investigation for Multioutlet Assemblies”.  This definition tells us that a work surface is “A horizontal or nearly horizontal surface used to perform tasks. a) Normally dry use work area surface (example: office desk, table) b) Normally dry use work area located directly adjacent to a lavatory or other water source (example: kitchen sink countertop).

This standard defines a multioutlet assembly as “A surface, flush or freestanding assemblage consisting of a raceway and fittings or other enclosure provided with one or more receptacles for the purpose of supplying power to utilization equipment.

The importance of understanding the definition of a work surface is revealed when determining the placement of receptacles (210.52) and in determining the listing requirements for the devices used in these applications (406.5).

Section 32 of the UL 111 Outline of Investigation addresses the spill tests for these multioutlet assemblies that may be found in these applications.  This section is separated into the following tests:

32.1 General

32.2 Method I (Dry use work surface) which points to Section 6.3 titled “Work Surface and Counter top mounted multioutlet assemblies.”

32.3 Method II (Work area directly adjacent to a lavatory)

Method I tests for dry use work surface applications includes a test that requires a saline solution with a specific amount of table salt per liter of distilled water to be used in an acrylic cylinder of specific dimensions.  The dimensions of the cylinder are approximately 3 inches in diameter and 4 inches tall.  This is to be filled with 8 ounces of the saline solution which is then spilled in a specific manner on to the test subject.  

Method II tests for these work surface applications addresses when the work area is directly adjacent to a lavatory.  In this case the amount of saline solution is increased from 8 ounces to 64 fluid ounces and the acrylic cylinder is increase to 7 – ⅛ inches in diameter to 9-⅞ inches in height.  The spill test is conducted in the same manner as in Method I.

Pop-up assemblies listed to UL 498 must pass spill tests as well.  In the case of a UL 498 device, the container for the test is 7 – ⅛ inches in diameter to 9-⅞ inches in height and the amount of saline solution is 64 fluid ounces.