Since October 1, 2019, the New York City Fire Department’s Rule 3 RCNY 608-01, entitled “Outdoor Stationary Storage Battery Systems” has been in effect and applied to projects throughout NYC.

FDNY Rule 3 RCNY 608-01 applies to the installation and utilization of Outdoor Stationary Storage Battery systems that use new energy storage technologies such as lithium-ion, nickel-cadmium and others. Existing and proposed systems must comply with the requirements of this rule.

So how does this rule affect new projects?

If a project calls for the installation of a storage battery system, whether for backup power or to help reduce peak demand for car chargers and other electronics, Rule 608-01 may apply.

One exemption is for outdoor stationary storage battery systems with an aggregate rated energy capacity of not more than 250 kWh that are a component of individual motor vehicle charging stations and used for the purpose of motor vehicle charging.

Even though the mentioned system may be exempt, best practice calls for owners and operators to review Rule 608-01 and implement safe practices that would meet compliance.

In order to install or specify a battery storage technology for a project, that technology must be approved by the FDNY for use within NYC. The purpose of this approval is to ensure that the battery system meets FDNY requirements for fire safety. An ongoing issue with the systems is “thermal run away” fires. These fires are difficult to put out and have the potential to re-ignite after the fact.

The FDNY requires various laboratory tests and certifications indicating that these fire risks are mitigated.

For manufacturers interested in applying for these certifications, the TM-2 form must be completed and submitted to the FDNY for review either by the manufacturer themselves or by a person authorized by said manufacturer.

For owners and developers, a TM-1 form must be completed to permit systems that require approval under 608-01. The following items may be required in order to be in compliance:

  • A permit, for systems that fall under the medium and large size requirements.
  • In order to receive FDNY approval for the installation of any system the following documentation is required;
  • any Department of Building applications filed involving the system,

-a department equipment approval for each unit,
-a site plan; and
-a commissioning/de-commissioning plan.

  • General Design and Installation requirements must be followed as subject to Table 2.
  • The FDNY classifies the system size based on the cumulative power rating for a facility rather than individual components to ensure adequate fire safety measures are being followed.  

If you have any questions regarding the FDNY rule 608-01 regarding your Stationary Storage Battery System or require assistance in achieving compliance with this new rule, please contact Walden’s design specialists that have experience with the Department of Building and FDNY permit requirements.

For more information you may visit the Fire Department’s website ( and the NYCRULES’ website (