NFPA 855 Changes in the 2026 Edition

NFPA 855 Changes in the 2026 Edition 

As the renewable energy sector continues to grow, so does the importance of ensuring the safety of energy storage systems (ESS). The newly released 2026 edition of NFPA 855: Standard for the Installation of Stationary Energy Storage Systems brings several critical updates that will affect how we manage risk, design systems, and plan for emergencies. Here’s what every H&S professional needs to know.

Since its first edition in 2020, NFPA 855 has become the benchmark for safely deploying batteries in homes, businesses, and utility-scale projects. It’s still a young, standalone standard, but each edition has brought meaningful refinements, and 2026 is no exception.

2023 Edition

In the 2023 edition, initiation was limited to air-aspirating smoke detection or radiant-energy detection. In the first draft of the 2026 edition, the committee clarified the intent: “There is a need to correlate the detection technologies with NFPA 72. Specifying ‘air-aspirating’ as the method of smoke detection was inappropriate; other forms of smoke detection can be utilized based on the conditions present at the location.”

Under the earlier edition, if only a portion of an existing facility were newly designated to store lithium-ion batteries, then, even if the building already had detection and notification systems, an additional radiant-energy or air-aspirating detector would have been required. The 2026 edition changes that approach by aligning with the National Fire Alarm and Signaling Code (NFPA 72) and allowing the use of other suitable smoke-detection technologies. However, it’s important to note that the IFC 2024 still uses the 2023 edition of NFPA 855 language. As many jurisdictions are only now adopting the 2024 I-Codes, be aware of local amendments that may update 2023 wording to reflect the 2026 edition.

Also, UL Standard 2684, Video and Thermal Image Detectors for Fire Alarm Systems, was most recently revised in August 2025. While many products are still in the process of obtaining listings, expect more off-the-shelf solutions to be listed to UL 2684 as the market catches up.

·        2023 edition, section 14.3.2.1.2 – “The rooms or spaces shall be provided with a fire alarm system activated by an air-aspirating smoke detector system or a radiant-energy detection system with occupant notification installed in accordance with NFPA 72.”

·        2026 edition, section 14.3.2.1.2 – “The rooms or spaces shall be provided with a fire alarm system activated by a smoke detector system, a thermal image fire detection system, or a radiant-energy detection system with occupant notification installed in accordance with NFPA 72.”

New & Emerging Technologies More Explicitly Covered

The first step when using NFPA 855 is to review the scope. The standard applies only to certain kilowatt-hour (kWh) ratings by battery technology. Where energy ratings are small (which limits energy density), code requirements might not apply. For example, a small server room in a business-occupancy building or a battery backup for a small carbon-dioxide (CO₂) skid might be <20 kWh for lithium-ion chemistry and <70 kWh for valve-regulated lead-acid (VRLA) batteries.

The 2023 edition Table 1.3 subdivides battery technologies and capacitor energy storage systems. However, the 2026 edition does not segregate them; instead, it lists more battery chemistries in simple alphabetical order, with the threshold for other battery technologies at the bottom. Keep in mind, the values mentioned in Table 1.3, is the nameplate capacity or maximum stored energy, not the usable capacity. Chapter 1 & tech-specific tables in Chapter 9 have been updated. 

NFPA 855: 2023 Edition	NFPA 855: 2026 Edition
Focus on established chemistries; Conservative threshold for “other.”	The code names new chemistries explicitly; other listed chemistry thresholds remain the same.
Included Lead-acid, Ni-Cad, Ni-MH & Ni-Zn, Lithium-ion, Sodium nickel chloride, flow batteries, flywheel ESS, and electrochemical double-layer capacitors.	Added Hybrid supercapacitors, Iron-air, aqueous, Lithium metal, Ni-Fe, Nickel-hydrogen, Sodium sulfur, Zinc-air, aqueous, Zinc bromide, and Zinc manganese dioxide (Zn-MnO2).

Although the 2024 edition of the International Fire Code (IFC 2024) adopts many thresholds from NFPA 855 (2023), facilities using a listed chemistry that exceeds the old “other battery technologies” threshold, but remains below the listed chemistries under the 2026 edition, may have flexibility when working with the Authority Having Jurisdiction (AHJ). Remember: early communication with the AHJ is crucial.

Clearer Definitions

The 2026 edition expands Chapter 3 definitions to reduce ambiguity, defining commonly used terms, including Fire Risk Assessment and Registered Design Professional.

The 2026 edition also updated the Qualified Person to list knowledge and training related to specific energy storage systems:

·        2023 edition: “Qualified Person – One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved.”

·        2026 edition: “Qualified Person – One who has skills, knowledge, and training related to the construction and operation of energy storage systems and electrical equipment and installations and has received safety training to recognize, avoid, and mitigate the hazards”

This matters because the code clarifies the qualifications for individuals performing consulting operations and risk assessments.

Annex G in the 2026 version follows with: “The risk assessment design process should be directed by a registered design professional experienced in fire protection engineering and in energy storage risk assessment and plant operation of the type of, or similar to the plant under consideration.” The 2023 edition referred to “parties” rather than a registered design professional (PE).

Hazard Mitigation Analysis (HMA): From Optional to Required

Chapter 4 in the 2026 version introduces significant changes, now making Hazard Mitigation Analysis the default. Chapter 9 removed the “Maximum Stored Energy” table.

One of the most significant changes in NFPA 855 (2026) is its approach to HMA—a formal safety risk assessment for an energy storage installation.

NFPA 855: 2023 Edition	NFPA 855: 2026 Edition
Code only required an HMA in some instances.	HMA is the default requirement for virtually all ESS installations under the scope of the code, unless modified in later chapters.

For example, per Section 9.3.2, an HMA is not required for lead-acid and aqueous nickel-based battery ESS. This reflects that traditional lead-acid and nickel-cadmium systems, whose risks are better characterized, with a long history with these chemistries, may not always require an HMA by default.

Previously (in the 2020/2023 editions), facility owners only had to conduct an HMA if their project triggered specific criteria. For example, if owners wanted to install more energy storage than the maximum allowed in Chapter 9, they could do so after the approval and performance of an HMA. If the project in question stayed under those limits (and above the threshold quantities in Chapter 1 for the given battery chemistry), no HMA was necessary. In practice, this meant modest-sized installations often avoided a hazard mitigation analysis under the old rules.

Improved Emergency Response Planning and Training

In the 2023 edition, the code called for emergency planning and training in Section 4.3. The plan details multiple requirements, for example, first-responder information, system layout, shutdown procedures, and responsible contacts. The new edition adds when and how to establish this plan and coordinate with the AHJ.

A new Section 4.3.3 covers the ERP (Emergency response plan) and training. The code lists the minimum requirements for the plan explicitly. The response plan should address minimum, mitigation, preparedness, response, and recovery. The new edition also requires the emergency operations plan to be reviewed annually, with a refresher training conducted annually, and emergency responders notified of the training dates and locations.

Fire Control & Suppression

Sprinkler requirements under NFPA 13 (or equivalent) remain in place. In the 2023 edition, Section 4.9.3 focused on “alternate fire protection systems,” with applicability based on fire and explosion testing. The new 2026 edition reframes this as “automatic fire control;” the “alternate” label is removed, and NFPA 13 is now included within a broader section on automatic fire control and suppression standards.

Emergency Power Supply Systems

A new Section 4.10 addresses Emergency Power Supply Systems (EPSS) and Stored Emergency Power Supply Systems (SEPSS):

·        Critical safety systems that rely on power must be provided with reliable EPSS or SEPSS power in accordance with NFPA 110 or NFPA 111.

Per Section 4.10.22, the design for the EPSS should be available to the Fire Protection Engineer (FPE) of record and the AHJ for review and approval.

Stricter Fire Testing Requirements: UL 9540A + Large-Scale Fire Tests

A notable change in NFPA 855 (2026) is the strengthening of fire and explosion testing for ESS. In light of recent battery fires, the code ensures system testing under realistic worst-case conditions, not just lab-scale scenarios. NFPA 855 (2026) now explicitly requires large-scale fire testing (LSFT) in conjunction with Underwriters Laboratories (UL) 9540A testing, demonstrating that systems can withstand and contain severe thermal runaway events.

UL9540A is the Test Method for Battery Energy Storage Systems (BESS), which is a protocol for testing ESS, initiates thermal runaway at the cell, module, unit, and installation levels of an ESS product, and collects the resulting data to help evaluate the fire and explosion hazards. However, as currently written, if a product passes at a given level, the test concludes and does not have to proceed to the next level. The argument against stopping the test is that the data collected may not present a realistic fire scenario, and therefore cannot truly be considered “large-scale”.

UL 9540A (a UL test method) forces thermal runaway at the cell, then module, unit, and installation levels, collecting data at each stage. However, UL 9540A can conclude early if a level passes (e.g., no module propagation), meaning some large systems would have never been tested as a whole. The 2026 edition addresses this gap.

The old Section 9.1.5 (Fire and Explosion Testing) has been moved to a new Section 9.2. Now, per Section 9.2.1.2:

·        Where cell thermal runaway releases flammable gases during a cell- or module-level test, an additional unit-level test should be conducted involving intentional ignition of vent gases to assess fire/deflagration hazards; and

·        The large-scale fire testing required should be conducted or witnessed and reported by an approved testing laboratory, which will characterize the gas composition and demonstrate that a fire involving one ESS unit will not propagate to an adjacent unit.

Technology-Specific Requirements and Thermal Runaway Propagation Prevention (TRPP) Systems

NFPA 855 (2026) expands the technology-specific requirements in Chapter 9 to include the new chemistries. Also, Section 9.7.6.6 now addresses Thermal Runaway Propagation Prevention (TRPP) systems. Compliance with ASME B31.1 or ASME B31.3 (as applicable) should be documented as part of the UL 9540 listing. These systems are an active, automatic system for ESS that detects precursors to cell thermal runaway (e.g., off-gas or abnormal temperature) and actuates a targeted suppression/cooling medium to absorb heat and stop propagation to adjacent cells, modules, or racks. Passive features (barriers, spacing, enclosures) are complementary but do not, by themselves, constitute TRPP.

Storage of Lithium Metal or Lithium-Ion Batteries

While Chapter 14 (storage of Li-ion or Lithium-Metal batteries) did not change significantly, there are notable updates.

The fire detection section has been reworded to allow for a smoke detector system, a thermal-image fire detection system, or a radiant-energy detection system (previously: air-aspirating smoke detection or radiant-energy detection only). Additionally, outdoor storage language is aligned to include thermal-image detection along with radiant-energy detection.

NFPA 855: 2023 Edition	NFPA 855: 2026 Edition
Required to provide fire detection in the battery storage areas using either air-aspirating or radiant-energy technologies. Didn’t explicitly mention thermal-imaging detection, even though the basic working principle in this technology comes under radiant-energy-based.	Section is reworded to initiation using “smoke detection.” Explicit use of “air-aspirating” is removed. Explicitly adds “Thermal image fire detection”. A new section provides an exception for the temporary storage of batteries at SoC 50% or less at the installation locations.

2026 Edition

A new section, 14.1.3, allows batteries, modules, and ESS temporarily staged or stored at an installation site to not comply with Chapter 14 when the state of charge (SOC) ≤ 50% and subject to other conditions.

Frequently Asked Questions (FAQ)

A.   What is NFPA 855?

NFPA 855 is the standard for the installation of stationary energy storage systems (ESS). It establishes safety requirements for the deployment of batteries in homes, businesses, and utility-scale projects.

B.   What are the biggest changes in the 2026 edition of NFPA 855?

The 2026 edition expands the scope to cover more battery chemistries, makes Hazard Mitigation Analysis (HMA) the default, strengthens professional qualifications, requires stricter fire testing, and adds new guidelines for emergency planning, EPSS/SEPSS, TRPP systems, and lithium battery storage.

C.   How can companies prepare for compliance with NFPA 855 (2026)?

Companies should plan for a required HMA, coordinate early with the AHJ. This ensures that detection, suppression, and testing meet the new code language. Involvement of a licensed PE is crucial to compliance.

D.   How do TRPP systems improve safety?

The code now addresses Thermal Runaway Propagation Prevention (TRPP) systems and requirements. They are an active system that prevents a failure in one cell or module from spreading to others. This reduces the chance of large-scale fires.

E.   Do I always need to perform a Hazard Mitigation Analysis under NFPA 855 (2026)?

Yes, a Hazard Mitigation Analysis (HMA) is now the default requirement for most ESS installations. Limited exceptions exist for lead-acid and aqueous nickel-based systems, whose risks are already well understood.

F.    How does the 2026 edition impact lithium-ion battery storage?

It broadens acceptable fire detection methods, allowing broader smoke detection and thermal imaging in addition to radiant-energy detection. It also provides flexibility for temporary storage when the state of charge is ≤50% under specific conditions.

G.   How will the changes to NFPA 855 affect project timelines and costs?

Most projects will now need to budget for a formal HMA, expanded testing, and annual emergency response training. While this adds requirements, it supports smoother approvals with AHJs and safer long-term operation.

H.   Who qualifies to perform risk assessments under NFPA 855 (2026)?

Risk assessments must be led by a registered design professional, typically a licensed PE with fire protection and ESS experience. This change clarifies that general consultants or “parties” no longer meet the requirement.

I.    What do the new testing requirements mean for manufacturers?

Manufacturers must now provide both UL 9540A and large-scale fire test results. These tests confirm systems can withstand thermal runaway and prevent fire propagation to adjacent units.

J.    What are the current installation codes and standard requirements for ESS in the US related to fire and explosion testing?

The 2023 edition of NFPA 855 and the 2024 edition of the International Fire Code require fire and explosion testing to be conducted in certain situations. Both editions reference that such testing shall be conducted on a representative ESS in accordance with UL 9540A, the Standard for Test Method for Evaluating Thermal Runaway Fire Propagation in Battery Energy Storage Systems.

K.   What fire and explosion test method will the 2026 edition of NFPA 855 specify?

UL Solutions experts, fire officials and industry stakeholders are actively drafting stricter fire and explosion testing protocols in the upcoming 2026 edition of NFPA 855. The current draft specifies that fire testing must be conducted in accordance with UL 9540A and, in certain instances, incorporate large-scale fire testing.

L.    Will UL 9540A address large-scale fire testing after the release of the 2026 edition of NFPA 855?

UL 9540A will evolve during the coming months to address large-scale fire testing criteria in NFPA 855.  A dedicated task group within the UL 9540A Technical Committee has been diligently working the last year on development of a test method to address the increased demand for robust fire and explosion testing scenarios.

M.  Can test methods other than UL 9540A be used for ESS large scale fire and explosion testing?

The current and next edition of NFPA 855 specify that UL 9540A is the required test method for ESS installation. In certain instances, ESS installations may require additional large-scale testing. Organizations may turn to alternative test methods for large-scale testing. However, these test methods are not widely accepted and should be considered on a case-by-case basis. 

N.   Where can UL Solutions conduct large-scale fire testing?

UL Solutions offers large-scale fire testing out of several facilities in the US, China and Korea.

Large batteries present unique safety considerations, because they contain high levels of energy. We remain committed to helping battery innovators enhance energy storage capacity with services to support greater safety, performance and reliability.

 

O.   What are the updates to the latest edition in pointwise of UL 9540A published on March 12, 2025?

The latest edition of UL 9540A covers key improvements that serve to streamline testing and drive towards consistency among test labs when conducting this test program.  Primary changes consist of the following:

    I.        Adding definition for thermal runaway propagation and clarify the criteria for establishing cell to cell propagation.

  II.        Specifying thermocouple locations  and adding option for a continuous thermal ramp for the Cell Level Test.

III.        Updating Module Level Performance Criteria to include a temperature limit for the module casing.

 IV.        Replacing the NFPA 286 fire test room with an instrumented wall for the Unit Level Test for residential BESS.

   V.        Requiring the inclusion of test summaries from previous level tests in Module, Unit, and Installation Level Test reports.

 VI.        Introducing test methods for high-temperature, lead acid, and nickel cadmium batteries, and refine the test method for flow batteries.

VII.        Enhancing unit level testing protocols for Rooftop and Open Garage installations.

VIII.        Permitting the Use of Gardon heat flux gauges for the Unit and Installation Level Tests.

 IX.        Implementing the use of flame ionization detection to measure total hydrocarbons as well as hydrogen measurements for the Unit and Installation Level Tests.

About Author:

Dr. Arindam Bhadra is a Fire safety consultant  & ISO Auditor based in Kolkata, India, with over 20 years of experience in Fire safety systems. He’s currently founding director of the Sprinkler Fire Safety Awareness and Welfare Foundation & SSA Integrate. He working on Fire Safety awareness, training, consultancy & Audit in same field. Dr. Arindam Bhadra is popularly known as "Fire ka Doctor" because of his expertise in fire safety, prevention, and awareness, helping people and organizations stay safe from fire hazards. He is Member of NFPA, Conformity Assessment Society (CAS), FSAI, Institution of Safety Engineers (India) etc. He is certified fire Inspector and certified Fire Protection professional.

NBC - LIFE SAFETY REQUIREMENTS FOR DATA CENTRES

NBC - LIFE SAFETY REQUIREMENTS FOR DATA CENTRES

There are no specific annex in NBC 2016 Part 4 Fire & Life Safety regarding life safety requirements for Data Centres. In upcoming NBC 2025 (currently in Draft & BIS now accept valid comments from professionals) add new annex named ANNEX G (Clause 6). This Article just recommendation to BIS can include in upcoming NBC 2025, Writeups have copy from Draft NBC 2025. In NBC 2016 ANNEX G (Clause 6) indicates Commercial Kitchens. 

G-1 GENERAL

Data centres are classified under Group E Business occupancy and in particular as E-6 sub-occupancy considering its primary use, scale, and presence of process equipment. A comprehensive fire risk assessment should be conducted at the planning stage and periodically during operation. Assessments must include ignition sources, fire load, electrical risks, HVAC systems, etc. For guidance on the facilities and infrastructure of datacentres, refer the following good practices.

G-2 BUILDING DESIGN AND CONSTRUCTION

G-2.1 The fire resistance rating for the structural and non-structural elements shall be based on guidelines as per approved and accepted standards. The fire rating shall be validated and certified with a view to meeting the requirements of Table 1 above. In the absence of any validated/certified rating, guidance may be obtained from the information available in Annex C.

G-2.2 An anti-static floor system is highly recommended to prevent electrostatic discharge and support cable management. The data centre must be completely isolated from dust, water, vibration, and humidity. All external openings should be sealed, and no water sources or pipelines should be routed through or above the data centre, UPS room, or communications room to eliminate risks of leakage or moisture intrusion. However, any location of chillers at higher heights be opted considering the operational efficiency, the same should be adequately considered in the structural design; authorities may consider exempting the increased building height in such a case. Such floors shall have no other occupancy else considered in the calculation of floor area ratio and height.

G-2.3 Server rooms, battery banks, fuel storage, and other high-risk areas should be physically separated using fire-rated assemblies. Cable trays and ducts openings for cable trays and ducts should be sealed with materials having fire resistance rating of the compartment.

G-2.4 The number of basements should be kept as minimum and it shall not be more than 2. The basement(s) shall be within the building line and their total area shall not exceed the area of ground floor. Basement must not use for electronic garbage.

Basement-Specific Considerations

·        Moisture Control:  A primary concern for basements is the potential for water or moisture leakage from other parts of the building. 

·        Plumbing Isolation: Keep plumbing, except for fire suppression and HVAC systems, away from the data center space to minimize leak risks. 

·        Sealed Enclosure:  Data centers should ideally be "room-in-a-room" to ensure none of their walls form the external building facade, preventing air and moisture leakage. 

·        Air Filtration:  Use appropriate filters, such as MERV 8 or higher, to trap contaminants, preventing them from entering the sensitive electronic environment. 

G-2.5 The parking requirement shall be arrived at considering the requirement for administrative building (at 1 ECS per 100 m2). The parking requirement for the data centre/utility building shall be based on the actual required number and area (of trucks) for which additional considerations of loading and unloading spaces for services. Rack Placement consideration emphasize the hot-aisle, cold-aisle configuration for rack placement, where racks are arranged in alternating rows with their fronts (air inlets) facing the cold aisles and their backs (air exhausts) facing the hot aisles. This strategy, detailed in publications like the "Thermal Guidelines for Data Processing Environments," prevents the mixing of cold and hot air, ensuring efficient cooling by directing chilled air into the front of the racks and the warm exhaust air from the back of the racks back to the cooling units.  

Requirements for Fire Truck Movement:

·        Minimum Approach Width:  A clear, unobstructed path of at least 4.5 meters must be maintained for the fire tender's movement around the building. 

·        Height Clearance:  The height clearance for the approach path must be a minimum of 5 meters to allow for the passage of the fire truck. 

·        Turning Radius:  A minimum turning radius of 9 meters is required for fire tenders weighing up to 45 tonnes to facilitate their movement on site. 

·        Open Spaces:  The approach to the building must have a width of not less than 6 meters on all sides, in addition to the required turning radius. 

·        Remote Access: Buildings require at least two means of access to the site, positioned remotely from each other, to ensure fire units can move freely and effectively. 

Note: If above criteria not fulfil then consideration for the fire truck and its movement shall be ensured in consultation with the local Fire Authority.

G-2.6 Lifts when planned to consider respectively for administrative building (as passenger lift as per Part 8/Sec 5A of the Code) and for the datacentre building (as special goods lifts and special service lifts, for which OEMs should be consulted considering the size, speed and weight of payload; and any required special requirement.

G-2.7 Heights of stories should be arrived at based on the size of racks opted and the associated services (like cooling/ducting) and the same is effectively addressed in the structural design. The total height of the datacentre building shall be arrived based on the FAR (which shall not exceed 5.0 and only Type 1 construction, see also Table of Part 3 ‘Development Control & Promotion Rules and General Building Requirements’ of the Code). Ground coverage shall not exceed 60 percent considering the peculiar requirements and the essential nature of these buildings which are required in the society in the current times.

G-2.8 Environmental Guidelines

·        Temperature: Recommends maintaining equipment within specific temperature ranges to ensure reliable and efficient operation. 18°C to 27°C (64°F to 81°F) for most common data center classes.

·        Humidity: Maintain relative humidity levels within an acceptable range, typically between 20% and 80% relative humidity. Low humidity can cause ESD, while high humidity leads to condensation and corrosion. 

·        Rate of Change: Control the rate of change for both temperature and humidity to prevent rapid shifts that can damage equipment. 

·        Prevent ESD: Low humidity can cause electrostatic discharge (ESD), which can damage or destroy sensitive electronic components. 

·        High-Density Cooling: For high-density IT equipment, consider advanced cooling solutions like direct liquid cooling in dedicated areas with independent controls. 

G-3 FIRE DETECTION SYSTEMS

G-3.1 Air Sampling is use of very early smoke detection apparatus (VESDA) in server areas. This system called Aspirating System. It provides extremely sensitive, pre-emptive fire detection by continuously drawing air samples through a network of pipes to a central laser-based detector that identifies microscopic smoke particles before a fire escalates. Pipe network design as per OEMs instructions. These systems, which require multiple alert and alarm thresholds, are characterized by very tight coverage limits, typically 200 square feet per detector.  Aspirating system can integrate with building management systems, fire alarm control panels, and suppression systems for comprehensive fire safety. Advanced aspirating models use sophisticated techniques, like CMOS imaging and multi-directional laser scattering, to accurately distinguish smoke from dust and other pollutants, significantly reducing false alarms.  As with any tool, proper maintenance is important. Set up a schedule, or use a fire prevention expert to assist you, to regularly calibrate your equipment, check for proper airflow patterns, and ensure the aspirating systems remains in proper working order.

G-3.2 For other requirements on fire detection and alarm system 4.9 be referred.

G-4 FIRE SUPPRESSION SYSTEMS

G-4.1 The fire suppression system in data centres shall be designed to ensure both operational continuity and protection of sensitive equipment. The preferred suppression technologies clean agent extinguishers (such as Inergen, HFC-236fa and HFC-227ea based system or equivalent) should be available throughout data hall areas. Aerosol extinguishing systems can be use a cutting-edge approach to fire suppression. These systems shall be effective in suppressing fires without leaving any residue, making them safe for electronic and electrical installations. Clean agent systems are essentially discharge nozzles connected to a pressurized tank that releases the contents of the tank upon system activation. The system can be activated by electronic means, such as smoke detectors, or by mechanical means, such as fusible links. Tube based suppression system at Rack level is also cutting-edge approach to fire suppression. Fire Suppression system design as per OEMs guideline. As with any tool, proper maintenance is important. Set up a schedule, or use a fire prevention expert to assist you, to regularly calibrate your equipment, check for proper patterns, and ensure the Fire Suppression systems remains in proper working order.

G-4.2 All critical areas within the data centre, including server rooms, network rooms, UPS and battery areas, and under-floor and overhead spaces, must be covered comprehensively by the fire suppression system.

G-4.3 The suppression agents should be ozone-friendly and compliant with international environmental norms. The recharge process must be easy, with minimal downtime, and the equipment should be easy to test periodically.

G-4.4 As an alternative to clean agents, special automatic fire sprinkler systems can be installed. These systems are referred to as “pre-action sprinkler systems.” Pre-action sprinkler systems are interlocked with electronic detectors, such as smoke or heat detectors, and activate only when the electronic detection system actuates. As an additional layer of protection from accidental activation, a single sprinkler head and an electronic detector need to activate before water fills the normally dry piping that protects sensitive rooms. When the system is not active, its piping is dry, and no damage would occur if a sprinkler head accidentally or inadvertently discharged (because the electronic detection system also must actuate to fill the sprinkler system with water). This type of sprinkler system is referred to as a double-interlock pre-action sprinkler system.

G-4.5 An early warning fire detection and suppression system shall be integrated with the fire alarm and Building Management System (BMS) for real-time monitoring and response. The system shall be engineered to offer reliable and quick suppression to minimize damage and downtime.

G-5 ELECTRICAL AND HVAC FIRE SAFETY (see also Part 8/Sec 2 and Part 8/Sec 3 of the Code)

G-5.1 UPS, transformer, and generator rooms should be separated with fire-rated partitions/doors and have independent suppression systems. Should the need arise, the generators can be placed one over the other/stacked (upto 5 numbers) parallel to the data centre building, but adequate fire safety should be ensured for which OEM’s advice and specialist literature should be referred. Height of datacentre shall be the upper limit for height of DG sets, if stacked. Integrate smoke detectors into the system to provide early warning of fire hazards, such as from short circuits or overheating components. 

G-5.2 Wherever batteries are provided, the same shall be segregated by 120 min fire rated construction. Ventilation to the room shall be provided as per manufacturer’s instructions. Ventilation system must provide a minimum of 1 cubic foot per minute per battery cell and operate based on hydrogen concentration.

Battery room,  generally requires a hydrogen gas detection system to mitigate explosive risks from lead-acid batteries. The system should include hydrogen sensors located high in the room where the gas accumulates, smoke detectors for early fire detection, and an integrated system to activate alarms, ventilation, and potentially trigger a safe shutdown of the charging system if hydrogen levels exceed a safe threshold, such as 1% by volume. Mount hydrogen sensors near the ceiling, as hydrogen gas is lighter than air and rises and accumulates at the highest points of the room. When hydrogen concentration reaches a preset level (e.g., 1% by volume), an audible and visual alarm should be activated to alert personnel. Integrate smoke detectors into the system to provide early warning of fire hazards, such as from short circuits or overheating components.

G-5.3 Air conditioning and ventilating systems shall be so installed and maintained as to minimize the danger of spread of fire, smoke or fumes from one floor to other or from outside to any occupied building or structure. Additionally, air inlets must be installed near the floor, while exhaust outlets must be placed at the high point of the room, to exploit hydrogen's low density and upward movement, maximizing ventilation efficiency. (hydrogen is lighter than air and diffuses upwards very rapidly)

G-5.4 Supply air ducts, fresh air and return air ducts/ passages must include fire dampers and smoke detectors (see 3.4.8.4).

G-5.5 Insufficient power capacity design for a data centre can result in various issues such as system downtime, data loss, Increased cost, reduced performance, regulatory non-compliance. Ensuring a robust power capacity design is crucial for the reliable and efficient operation of data centres.

G-6 MEANS OF EGRESS

G-6.1 Exit Access

Exits for shall be provided on each floor or compartment in accordance with 4.4.2. All exits should be unobstructed, illuminated, and clearly marked.

G-6.2 Staircases and Corridors

Staircases must be enclosed, fire-rated, and positively pressurized to prevent smoke ingress. Staircases shall be of minimum 1.5 m in width, and 2 numbers of it will be required in the datacentre building. Staircase for administrative building shall be arrived at using clause 4; in any case, minimum 2 staircases are required.

G-6.3 Emergency Lighting and Signage

Emergency lighting consistent with emergency system for the building shall be provided. Addressable emergency exit lighting system is recommended, adaptive type exit signages can also be used.

G-7 MEP, FIRE FIGHTING, AND SEISMIC SUPPORT REQUIREMENT

G-7.1 Earthquakes can cause downtime, data loss, service disruptions, fire, etc. Seismic bracing is essential to secure MEP equipment and systems, safeguarding them against the threats posed by earthquakes.

G-7.2 Non-structural measures focus on protecting operational components. These include seismic-rated mounting systems for equipment racks, secure cable pathways, MEP and fire fighting services to avoid disconnections, and reinforced architectural features like ceilings and raised floors. These elements must meet seismic standards to ensure systems stay operational during and after an earthquake.

G-7.3 Seismic analysis/calculations should be carried out based on Part 6 ‘Structural Design, Section 1 Loads, Forces and Effects’ of the Code and IS 16700. Each nonstructural component’s seismic interactions with all other connected components and with the supporting structure shall be accounted for in the design. The component shall accommodate drifts, deflections, and relative displacements determined in accordance with the applicable seismic requirements of standards.

G-7.4 Each straight pipe/duct/cable containment run with two or more supports requires a minimum of two transverse braces (perpendicular to the run) and one longitudinal brace (parallel to the run).

G-7.5 Wire rope angular bracing should be seismic certified/tested by third party accredited lab as per method of testing for rating seismic and wind restraints. Rigid angular bracing and modular support system should be analyzed for both tensile and compressive loads for strength and serviceability for the maximum length of element being used in worst case condition as per load combination as mentioned in standards.

G-7.6 Calculate static and dynamic loading due to wind forces required to select/design vibration isolators, bases and seismic and wind restraints for outdoor and roof top equipment’s/services. The calculation of wind load shall be as per Part 6/Sec 1 of the Code. Worst case between seismic loads and wind loads shall be considered for supporting and vibration isolation.

G-8 SECURITY

G-8.1 It is recommended that all doors shall be access controlled measures to restrict entry to authorized personnel only, preventing unauthorized access and protecting sensitive data and infrastructure. This is achieved through a layered security approach including physical security for building entry, electronic systems like proximity card readers or biometric authentication for server rooms, and even integrated software for remote monitoring and control.

Key Elements of Data Center Door Access Control

• Layered Security: Access control is implemented in multiple layers, starting from the building's main entrance and progressing to more secure areas like server rooms.
• Racks level Security: Access to each individual server rack within a data center will be individually secured and controlled, not just the overall data center facility. This implies that, in addition to physical entry to the building and data center floor, each specific rack needs separate authorization for access, typically using systems like keycard readers, biometrics, or PIN codes, to prevent unauthorized individuals from directly interacting with or tampering with the servers and equipment housed within the racks.
• Authentication Methods: Common methods include proximity cards, key fobs, smart cards, and biometric scanners (fingerprint or face scans). 
• Multi-Factor Authentication: Some areas may require a combination of authentication methods, such as both a card and a biometric scan, to grant access. 
• Monitoring and Alarms: Systems record every access instance, and alarms are triggered if doors are forced open or held open for too long, initiating an incident response. 
• Remote Control and Surveillance: Advanced solutions allow administrators to remotely monitor door status (locked/unlocked) and integrate real-time surveillance feeds into a central Data Center Infrastructure Management (DCIM) system.
• Integration with CCTV & Alarm Systems: Centralizing security management through the integration of third-party solutions like CCTV into the Command Centre platform enhances both visibility and response.
  
  For example, when access to a restricted area is denied, a critical alarm is triggered. Operators can utilize the Command Centre viewer to monitor the alarm and associated CCTV footage. Notifications can then be sent to the cardholder via email, text, or app alerts, guiding the appropriate response. This system streamlines the management of access denial alarms, consolidating all necessary information into a single interface, and facilitating seamless coordination between different security measures, enhancing overall protection.
• Visitor Management: Visitors are issued temporary photo badges and must be escorted by authorized personnel, with their access rights being logged and revoked upon departure or as per automatic time defined. 
• Mantraps: Some highly secure areas, like server rooms, utilize mantraps—two interlocked doors that prevent more than one person from passing through at a time—to serve as a final layer of defense. 
• Lights-Out Data Centers: In some advanced facilities, access is minimized, with remote management and automation systems handling operations, further reducing the need for physical entry and enhancing security. 

G-8.2 In line with safety requirements, access shall be open for the fire affected area.

G-9 OPTIONAL PERFORMANCE INDICATORS

For guidance on the performance indicators of datacentres, the following good practices may be referred.

Reference:
CED 46(26992) WC - Draft Code for Comments Only.
NBC 2016 Part 4.
NFPA Portal

About Author:

Dr. Arindam Bhadra is a Fire safety consultant  & ISO Auditor based in Kolkata, India, with over 20 years of experience in Fire safety systems. He’s currently founding director of the Sprinkler Fire Safety Awareness and Welfare Foundation & SSA Integrate. He working on Fire Safety awareness, training, consultancy & Audit in same field. Dr. Arindam Bhadra is popularly known as "Fire ka Doctor" because of his expertise in fire safety, prevention, and awareness, helping people and organizations stay safe from fire hazards. He is Member of FSAI, NFPA, Conformity Assessment Society (CAS) etc. He is certified fire Inspector and certified Fire Protection professional.