W-27 Supervision of Stationary Energy Storage Systems (ESS) in Group R-3 Occupancies (citywide)


The W-27 Certificate of Fitness is required for supervision of Stationary Energy Storage Systems installed in the Group R-3 occupancies (e.g. one- or two-family houses). The material will present information for accepted standards, requirements and procedures for the design, installation, operation, inspection, maintenance, and decommissioning of home energy storage systems.

This Certificate of Fitness is valid only for the specific person to whom it is issued and can be used anywhere within New York City.

  • New Application Fees: $25
  • Renewal Fees: $10
  • Application Reviewed Within: 1-2 Days
  • Renewal Cycle: 2 Year

Before You Submit Your Application

You must pass a written exam to get a B-28 Certificate of Fitness. All applicants should review the Notice of Exam and Study Materials.

How to Apply for the W-27 Certificate of Fitness

You can apply the W-27 COF online.

Quick Reference Guide for online application (PDF)

Applicants who need to take the exam must submit or upload following documents:


Applicants need to take and pass the exam at:

9 MetroTech Center
Brooklyn, NY 11201

How to renew the W-27 Certificate of Fitness

The W-27 COF can be renewed online. The W-27 COF holder must complete the following renewal affidavit. This affidavit must be uploaded as the “Supporting Document (in the Step 3) while submitting the W-27 online renewal.

For More Information

For questions, call 311 and ask for the FDNY Customer Service Center or send an email to FDNY.BusinessSupport@fdny.nyc.gov

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