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Knox Box Information and Requirements

The Nashville Fire Department requires the use of a rapid Entry Key Box System, or Knox Box, key box system. The Knox Box can securely store keys, access cards, key fobs, elevator keys, electrical shunt trips, or other vital information needed to assist emergency responders. This information is intended to outline the requirements for the proper type and installation of secure key boxes and padlocks.

Where We Require a Knox Box

A Knox Box is required on all commercial buildings and tenant spaces in Davidson County. When access to a building or area is necessary for life-saving or fire-fighting purposes or for access to fire protection equipment, a Knox Box will be required as designated by the Fire Marshal.

All occupancies and tenant spaces that have a fire sprinklers system, fire alarm system, special hazards, hazardous materials or high piled storage are required to have a Knox Box. The size of the key box shall be determined by the type of occupancy and hazards present.

Installation Location

Knox Boxes must be installed within three feet horizontally of the principle entrance door of the building or within three feet horizontally of another entrance to the building which is acceptable to the fire department. They need to be installed no less than 5.5 feet vertically from the threshold of the door and no more than seven feet vertically from the threshold of the door. However, the preference of the Fire Department is that Knox boxes be installed at the 5.5 foot level. Key boxes must be installed on the side of the building facing the street of address unless the Fire Department has approved another location.

In this diagram, a Knox Box may be installed anywhere in the gray shaded area only:

Knox Box installation drawing that shows area where a Knox Box can be installed around an entry door.

Access Controlled Gates

A Knox Padlock, Model 3770 for exterior applications, is required on all manual controlled gates, (pedestrian and vehicle), when the gates obstruct the fire lane and/or access to a building.


Tamper switches are permitted when desired by the owner.

For muti-tenant, multi-story and mid-size and larger commercial buildings, an appropriate size series will be required. Consideration should be given to the intended use of the building when selecting the key box.

How to Order a Knox Product

You may order directly from Knox at

When you order a Knox product, be sure to specify “Nashville Fire Department.”


If you have any questions about the installation of Knox Boxes, please email the Nashville Fire Department or call 615-862-5421.