Emergency Generator and Above Ground Fuel Tank Installations

Community Planning and Development Services Department
Inspection Services Division

General installation requirements

Adopted code standards regulating the installation of generators and associated above ground fuel storage tanks located at commercial and industrial properties.

Generators/tanks must comply with NFPA 110, NFPA 30, NFPA 37, NFPA 54, NFPA, NFPA 101, NFPA 55, NFPA 58, NFPA 70, and 2000 International Fire Code. 2000 International Mechanical Code, UL 142 and/or UL 2085. The above list of codes is intended to serve as a guide in determining code requirements. Installation requirements will differ depending on the fuel source used, and the quantity of fuel stored on-site.

Emergency Generator Permitting Requirements and Exterior Installations

New foundation/slab located on the exterior of a building

Completed Building Permit application.
2 Copies of architectural/structural drawings.
2 copies of a site plan showing the location of the generator on the site. Site plan must be drawn to scale. (Engineers scale) The site plan must indicate all principle structures on the property. Indicate any exterior doors and/or operational windows and air exhaust/intake vents.
Completed Mechanical permit application. Application must include the size of the fuel storage tank if applicable.
Completed Electrical permit application.
Information on the generator and fuel tank. This information should include information on the fuel tank listing (such as UL 142 or UL 2085 etc.) quantity of fuel stored, type of fuel e.g.: gasoline or diesel, venting locations, fuel fill information, manufactures cut sheets etc. Information on specific safety features such as overfill protection must also be included.

Installation on existing foundation/slab

Completed Mechanical and Electrical Permit applications. If the generator is being installed on an existing an existing slab/foundation, a structural evaluation report must be submitted. A Maryland State Professional Engineer or Architect must prepare this report. Report may be waived if substantial information on the existing slab/foundation construction is provided.
2 copies of the site plan indicating the location of the generator on the site. Site plan must be drawn to scale. (Engineers scale) Site plan must indicate all principle structures on the property. Indicate any exterior doors and/or operational windows.
Completed Mechanical permit application.
Completed Electrical permit application.
Information on the generator/fuel tank. This information should include information on the fuel tank listing (such as UL 142 or UL 2085 Etc.) Quantities of fuel stored, type of fuel e.g., gasoline, diesel, venting locations, fuel fill information, overfill protection, secondary containment, manufactures cut sheets etc.
Photos of the surrounding area can be very helpful.

TAKE NOTE: All exterior generator or fuel tank installations require approval from the City Planning Division. All applications for permits are subject to requirements set forth in the City Zoning Ordinance. It is advisable to speak to a City Planner prior to submittal for permits. City Planners may require screening around the installation. To contact the City Planning Division call 240-314- 8200.

In addition to City of Rockville requirements, all above ground fuel tank installations must be registered with Montgomery County Department of Fire and Rescue Services, Division of Emergency Management. 240-777-2300

Code questions may be directed to the Inspection Services Division Plans Review Staff by calling 240-314-8240.

Emergency Generator and Above Ground Fuel Tank Installations (.pdf)

Revised 05/19/2004