How many receptacle outlets are permitted on a 20A, 120V circuit in a commercial building?

In a commercial building, when determining the number of receptacle outlets that can be connected to a 20A, 120V circuit, the National Electrical Code (NEC) provides guidelines indicating that each receptacle is calculated based on the maximum load it can handle. According to NEC Article 210.21, for general-purpose branch circuits, each receptacle outlet is generally considered to draw a maximum load of 180 VA (volt-amperes).

The total capacity of a 20A circuit at 120V is:

20A x 120V = 2400 VA.

To find out how many receptacles can be installed, you divide the total circuit capacity by the load per receptacle:

2400 VA / 180 VA per receptacle = approximately 13.33.

Since only whole outlets can be installed, this leads to a maximum of 13 receptacle outlets on a 20A circuit.

Therefore, option B is the correct answer, as it accurately reflects the maximum number of receptacles that can be installed while adhering to NEC guidelines for a 20A, 120V circuit in a commercial setting.