Appeal 35026

OFC 1207.8.3 – Electrical Energy Storage Systems - Clearance to exposure

1207.8.3 Clearance to exposures.
ESS located outdoors shall be separated by a minimum of 10 feet (3048 mm) from the following exposures:
Lot lines.
Public ways.
Buildings.
Stored combustible materials.
Hazardous materials.
High-piled stock.
Other exposure hazards.
Exceptions:
Clearances are permitted to be reduced to 3 feet (914 mm) where a 1-hour free-standing fire barrier suitable for exterior use and extending 5 feet (1524 mm) above and 5 feet (1524 mm) beyond the physical boundary of the ESS installation is provided to protect the exposure.
Clearances to buildings are permitted to be reduced to 3 feet (914 mm) where noncombustible exterior walls with no openings or combustible overhangs are provided on the wall adjacent to the ESS and the fire-resistance rating of the exterior wall is a minimum of 2 hours.
Clearances to buildings are permitted to be reduced to 3 feet (914 mm) where a weatherproof enclosure constructed of noncombustible materials is provided over the ESS, and it has been demonstrated that a fire within the enclosure will not ignite combustible materials outside the enclosure based on large-scale fire testing complying with Section 1207.1.5.

This project is requesting approval to allow a reduction in clearance requirements for the installation of (6) ESS units for the Albina One Apartments. This community is situated in the heart of Lower Albina and the urban site constraints require reduced clearances to other exposure hazards.

Location of (6) ESS units is proposed to be on the north side of the property on a fenced concrete pad beyond the exterior building wall.
There is greater than 10’ separation from the property line and approximately 5’ from the exterior building wall.
The location of the batteries is in an area that is not accessible to the residents, remote from window openings and protected by 8’ tall fences on the north, east and west sides.
The building wall to the south of the ESS units has one door opening that allows access to an electrical room. The electrical room is secured and only accessible by authorized personnel.
The project has specified SolArk ESS units with integrated fire safety system composed of the following:
• Heat, smoke, & CO gas detectors
• BMU, Battery Module, and Cabinet Emergency Ventilation
• Alarm Indicators
• Aerosol Fire Suppression

We are seeking to reduce clearances from other exposure hazards based on the use of an integrated fire safety system that reduces risk of spreading flames to surrounding objects. See provided documentation of “L3 HVR-60 Fire Safety System Overview” that includes UL 9540A testing that is designed to meet stringent fire safety and building code requirements for battery energy storage systems. Please note that neither aerosol device was installed for the UL 9540A testing of the HVR. The positive test results occurred despite their absence, as the point of the test was to show the integrated cabinet level fire deflagration protection was adequate.
There are (2) aerosol systems: battery module aerosol and cabinet level aerosol. Each battery module has an aerosol fire suppressant that releases when encountering excessive heat. By locating the suppression system directly inside the battery next to the cells, the system is able suppress fires where it’s most needed.

The construction of the site has been prepared with a fire rated exterior wall at the building, non-combustible metal fencing and concrete pad. Together with a built in fire suppression system within batteries we believe it will satisfy the intent of the exception and provide an adequate level of protection.