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.

Fire Compartmentation Survey

Fire Compartmentation Survey 

Passive Fire Protection refers to the built-in safety measures designed to slow the spread of fire and smoke without requiring any action or trigger to operate. These systems are always on, quietly embedded into the structure of buildings, vehicles, and industrial equipment.

Passive fire protection is essential for building and managing different structures as part of fire safety. In environments where machinery are often used for long periods, electrical panels stay hot, and combustible materials are never far off. This makes electrical hazards like overloaded circuits or faulty wiring pose a significant ignition risk. In these settings, the real question isn’t if a fire will occur, but when—and when it does, seconds matter. For industries like construction, mining, logistics, and manufacturing, passive fire protection systems are often the first and only line of defense between a manageable incident and a full-blown shutdown.

Implementing passive fire protection methods help do the following:               

·        Contain the blaze at its source

·        Maintain safe evacuation paths

·        Preserve structural integrity during extreme heat

·        Protect critical infrastructure like server rooms or control panels

·        Give emergency responders valuable time to intervene

Across global markets, there are clear frameworks outlining fire-resistant design and maintenance standards. Some of which are the following:

·        NFPA 221 – US standard for High Challenge Fire Walls

• The Factories Act, 1948
• State Fire Safety Regulations (issued by State Fire Services)

·        BS EN 1366 – UK and EU guideline for Fire Resistance Tests for Building Services

·        AS 1530 – Australian methods for Fire Tests on Building Materials

·        ISO 834 – International Standard Fire Resistance Tests

·        The Fire Safety Order 2005 – UK law mandating fire risk assessment and mitigation

Fire Safety Laws in India Mandate Comprehensive Prevention Measures Across Sectors with Strict Compliance Requirements

Yes, compartmentation is a legal requirement in India to prevent the spread of fire, as mandated by the National Building Code (NBC), which specifies adherence to compartmentalization technology in building design for enhanced fire safety. Building codes, such as those found in Part 4 (Fire Safety) of the NBC, require the use of fire-resistant materials and construction techniques to divide buildings into compartments that can contain a fire.

Here are the four principles associated with implementing and ensuring effective passive fire protection:

1.   Containment: Fires grow by finding fuel and oxygen. Containment limits their reach by cutting off those resources using fire-rated barriers that resist penetration.

2.   Compartmentalization: Buildings and facilities are divided into zones, separated by fire-resistant materials. If one compartment catches fire, others remain protected for a designated time (e.g., 60 or 120 minutes).

3.   Structural Fire Resistance: Passive systems protect critical supports like steel beams or cable trays from rapid failure, allowing structures to stay upright longer under intense heat.

4.   Smoke and Toxic Gas Control: Passive fire protection doesn’t just focus on flames, as smoke, especially in enclosed or underground areas, is often the deadliest threat. Seals, dampers, and airtight closures prevent toxic fumes from traveling quickly through buildings.

The objective of fire compartmentation is to prevent the spread of smoke, gases, and flames. By subdividing the building with fire resisting construction, escape routes and high-risk or high-value areas are protected to ensure the safety of occupants and prevent extensive losses. 

Our teams will visually inspect all areas of the identified compartment lines within your building to assess their likely performance in the event of a fire. Defects in compartmentation lines can take numerous forms and require expert identification.

A suitable and sufficient fire risk assessment will typically involve a review of existing fire compartmentation measures through a sampling approach (walls, floors, voids, and shafts predominantly). 

Sampling can indicate the presence of significant issues, such as locating or confirming the presence of fire dampers, or establishing if existing measures meet the requirements of current guidance or other specific business resilience objectives.

Common defects include: simple penetrations, such as pipework entering or exiting a compartment with gaps, or inappropriate firestopping, allowing smoke or fire to potentially pass from one compartment to another. Other defects include: cabling, voids, ducts or linear gaps where compartment lines do not fully encapsulate the compartment. These defects are either latent, from the original build, or imposed from subsequent works (such as M&E events). Both are reiterating the need for regular inspection.

SSA INTEGRATE offer four distinct survey types

Indicative

SSA INTEGRATE will undertake all elements of the "standard" compartmentation survey, but only to selected floors or areas of a building. This will give you the same detail of electronic reporting within your chosen areas, from which our specialists will extrapolate results to enable indicative results to be presented for review.

Standard

Our standard survey is classed as "invasive". This means we will review all areas of the building, along with inspecting some harder to reach areas, such as roof voids, above suspended ceilings, and through inspection hatches in solid ceilings.

Enhanced

This option provides all the benefits of the "standard" survey, but includes additional indicative destructive works, including a percentage of identified areas for further investigation. In most cases, this will include 10% of soil vent pipes and 5% of behind architraves. Our teams will make good on all works, with follow-up attention by your chosen decorator.

Destructive

All elements of the "non-intrusive" survey, together with a pre-defined scope of intrusive works that are defined as a greater requirement than the enhanced survey option. The Fire Compartmentation Inspection Report Electronically recording all deficiencies. along with photographic evidence, the report will highlight the following:

A unique identifying number for each defect

Location

Room type

Required fire rating

Penetrating service type

Seal type required

Date and surveyor details

Due to full Compartmentation Surveys only being required for large, complex buildings, a Compartmentation Sample Survey could be more suitable for your organisation.  

·        Based on a minimum of 10 buildings. 

·        Surveys sample areas of each building (including samples of doors), to provide a general overview of compartment defects that are representative of all buildings.

·        Includes recommended actions.

·        Provides a risk rating for the buildings based on survey findings.

·        Significantly quicker and more cost-effective than a full Compartmentation Survey. 

FAQ:

What is a Fire Compartmentation Survey?  

Fire Compartmentation involves dividing a room, space, or storey of a building into fire-resistant compartments. This is achieved through the implementation and maintenance of fire-resisting floors and walls. Any openings or penetrations in the floors or walls, such as doors, windows, or service penetrations, must be installed and maintained to ensure the wall or floor remains fully sealed. A Compartmentation Survey assesses the condition of these elements of construction in providing fire-resisting compartmentation and identifies any subsequent defects.

When is a Fire Compartmentation Survey needed?  

Currently, there is no legal requirement specifying how often a Fire Compartmentation Survey should be conducted. Compartmentation should be reviewed as part of a regular Fire Risk Assessment (FRA) review process. If issues with compartmentation are raised in the FRA, particularly in hard-to-access areas, then a Compartmentation Survey is crucial to provide a comprehensive assessment. Compartmentation Surveys are also essential when serious defects are identified in either the common parts or inside the flats, as these cannot be accurately investigated during the FRA. 

What does a Fire Compartmentation Survey involve?  

Our Compartmentation Survey options are based on your needs and tailored to each of your buildings. As we don’t undertake remedial works following the Compartmentation Survey, you can be confident that our advice is impartial and reliable to avoid any unnecessary costs. Each survey is meticulously designed to assess various aspects, helping you select the most suitable choice for your organisation.

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.

Upcoming changes in NBC 2016 Part 4 ANNEX E (Clauses 5.1.4 & 6) E-4

Upcoming changes in NBC 2016 Part 4 ANNEX E (Clauses 5.1.4 & 6) E-4 

As on date 16-09-2025, latest version of NBC 2025 still not released. This post is tentative / draft only. Latest version of NBC 2025 is applicable for existing buildings when they are altered (see clause 5.1.4 and 6) or in the opinion of the authority constitute a hazard to the safety of the adjacent property or to the occupants of the building itself or are unsafe. Below Writeups is proposed only.

ANNEX E indicate ADDITIONAL REQUIREMENTS FOR HIGH RISE BUILDINGS

E-1 GENERAL (No Changes in upcoming NBC 2025)

E-2 EGRESS AND EVACUATION STRATEGY (No Changes in upcoming NBC 2025)

E-3 FIRE SAFETY REQUIREMENTS FOR LIFTS (No Changes in upcoming NBC 2025)

E-4 HORIZONTAL EXITS AND REFUGE AREA (Changes in upcoming NBC 2025)

E-5 ELECTRICAL SERVICES (No Changes in upcoming NBC 2025)

E-6 FIRE PROTECTION (Changes in upcoming NBC 2025)

E-7 FIRE AND LIFE SAFETY AUDIT (Changes in upcoming NBC 2025)

E-8 HELIPAD (No Changes in upcoming NBC 2025)

High rise buildings (15 m and above in height) shall receive special attention with respect to fire and life safety particularly with regard to planning, design, execution, maintenance and training so that the intended provisions of this Code are well implemented.

Horizontal Exit

Horizontal exits are a type of exit that protect occupants from the effects of fire without requiring vertical travel, such as within a stairwell. In some cases, they don’t even require occupants to exit a building.

So, its A way of passage from one building to an area of refuge in another building on approximately the same level, or a way of passage through or around a fire barrier to an area of refuge on approximately the same level in the same building that affords safety from fire and smoke originating from the area of incidence and areas communicating therewith.

Looking more closely at above definition, it is clear that there are two different types of horizontal exits. The first provides safety in another adjacent (often attached) building, while the second type provides safety in the same building, on the same level, using a fire barrier. So there is minimal elevation change and a fire barrier provides the separation between the area where the fire is and the area of safety. The construction of the horizontal exit must meet fairly specific design criteria.

Typically, horizontal exits are permitted provided other types of exits are also available. For compartments utilizing horizontal exits, at least half of the number of exits and half of the egress capacity required from that compartment must be provided by other types of exits. In the example below, two exits are required from each area and the horizontal exit and exit stairs are sized to accommodate the same number of people.

Areas A and C meet the requirement for at least half the required exits to be a component other than a horizontal exit. They each have a stair. Additionally, since they are sized the same, at least half the capacity also comes from a component other than a horizontal exit. Area B, on the other hand, does not meet that requirement, since the only exits available are the door in horizontal exit 1 and the door in horizontal exit 2. Therefore, a stair would need to be added so that occupants in area B have access to at least one exit that is not a horizontal exit. Then, the requirement for at least half the required number of exits and egress capacity would come from an exit other than a horizontal exit. The second horizontal exit would be permitted to remain, since it isn’t required—it would be seen more as a convenience door.

In order for a horizontal exit to be credited as an exit, there must be a path continuously available that leads from each side of the exit to stairways or other means of egress that lead outside of the building. If either side of the horizontal exit is occupied, the door leaves used in connection with the horizontal exit must be unlocked from the egress side.

Where a horizontal exit is used, the floor area on either side of the horizontal exit must be sufficient to hold the occupants of both floor areas. There must be at least 3 ft² (0.28 m²) clear floor area per person. In the example below, the horizontal exit is in the middle of the floor. Each side has 67 occupants. This results in a total occupant load of 134. This means that each side of the horizontal exit must have 402 ft² (122.5 m²) of clear floor area for the accumulation of occupants.

67 occupants + 67 occupants = 134 occupants
134 occupants x 3 ft²  = 402 ft²
134 occupants x 0.28 m² = 37.52 m²

The horizontal exit is required to be a fire barrier with a minimum 2-hour fire resistance rating, unless otherwise permitted for bridges serving as horizontal exits. The barrier must be continuous to the finished ground level. The image below shows this concept. 

The barrier does not need to extend below the lowest level that provides discharge to the exterior if the stories below do not have a horizontal exit and are separated from the level above by a minimum 2-hour fire resistance–rated construction. The image below details this concept. The basement level is separated from the remainder of the building by 2-hour fire resistance–rated construction and does not have a horizontal exit.

Similarly, the fire barrier serving as a horizontal exit is not required on other stories provided 1) the stories not containing the fire barrier are separated from the story with the horizontal exit by construction having a minimum fire resistance rating at least equal to that of the horizontal exit fire barrier; 2) vertical openings between the story with the horizontal exit and the open fire area story are enclosed with construction having a fire resistance rating at least equal to that of the horizontal exit fire barrier; and 3) all required exits other than horizontal exits discharge directly to the outside unless the building is protected throughout by an automatic sprinkler system. 
The image below shows this concept. The 2-hour fire resistance–rated fire barrier serving as a horizontal exit is only provided on the top floor. The level of exit discharge and the top floor are separated by 2-hour fire resistance–rated construction. Additionally, the exit stair enclosures are enclosed with 2-hour fire resistance–rated construction even though they only connect three stories.

Typically, doors in the horizontal exit must be swinging type doors that have a minimum 90-minute fire protection rating. In some situations, horizontal sliding doors may be permitted. Fire door assemblies in horizontal exits must be self-closing or automatic closing. For other than approved existing door assemblies, cross-corridor door assemblies in horizontal exits must be automatic-closing doors. Self-closing doors are not an option, which prevents the dangerous, but common, practice of wedging doors open.

The door leaf must swing in the direction of egress travel. For other than sleeping room areas in detention and correctional occupancies, where the horizontal exit serves as an exit for areas on either side of the fire barrier, and the opening is protected by a pair of swinging door leaves, the door leaves must open in opposite directions. There must be an exit sign on either side of the horizontal barrier identifying which door leaf swings in the direction of egress travel from that side. Instead of providing door leaves that swing in the opposite direction, door assemblies may be of any other approved arrangement, provided that the door leaves always swing with any possible egress travel.

A minimum 2-hour fire resistance–rated barrier is still required for bridges that serve as horizontal exits between buildings. The barrier must extend vertically from the ground to a point 10 ft (3,050 mm) above the bridge or to the roofline, whichever is lower. It also must extend horizontally at least 10 ft (3,050 mm) beyond either side of the bridge. For other than approved existing bridges, all openings in the fire barrier must be protected either with fire door assemblies or by a fixed fire window assembly that has a ¾-hour fire protection rating. This helps limit the risk of the bridge being exposed to fire conditions occurring inside the building. 

Bridges must be at least as wide as the door opening to which it leads, and new bridges must be a minimum of 44 in. (1,120 mm) wide.

Upcoming draft NBC part 4 annex E-4 HORIZONTAL EXITS says

E-4.1 Horizontal Exit

A horizontal exit shall be through a fire door of 120min rating in a fire resistant wall. Horizontal exit require separation with the adjoining compartment through 120min fire barrier. The adjoining compartment of the horizontal exit should allow unlocked and ease of egress and exits for the occupants using defend in place strategy.

Requirements of horizontal exits are as under:

a) Width of horizontal exit doorway shall be suitable to meet the occupant load factor for egress.

b) Doors in horizontal exits shall be openable at all times from both sides.

c) All doors shall swing in the direction of exit travel. For horizontal exits, if a double leaf door is used, the right hand door leaf shall swing in the direction of exit travel.

REFUGE AREA

The capacity, in inches, of means of egress stairways shall be calculated by multiplying the occupant load served by such stairways by a means of egress capacity factor of 0.3 inch (7.6 mm) per occupant. Where stairways serve more than one story, only the occupant load of each story considered individually shall be used in calculating the required capacity of the stairways serving that story.

An area of refuge is defined as “either (1) a story in a building where the building is protected throughout by an approved, supervised automatic sprinkler system and has not less than two accessible rooms or spaces separated from each other by smoke-resisting partitions; or (2) a space located in a path of travel leading to a public way that is protected from the effects of fire, either by means of separation from other spaces in the same building or by virtue of location, thereby permitting a delay in egress travel from any level.”

Purpose and Function

·        Temporary Shelter:

Provides a safe haven for people to wait for help when they cannot use elevators or stairwells during an emergency. 

·        Life Safety:

Helps prevent loss of life by providing a secure area away from immediate danger, such as smoke and flames. 

·        Crowd Control:

Prevents overcrowding in escape routes like stairwells, ensuring their functionality for emergency services. 

·        Ventilation and Smoke Control:

Designed to allow airflow, preventing smoke from accumulating and keeping the air breathable. 

Key Characteristics

·        Location: Typically found in high-rise buildings, often at intervals of every 7 floors or 24 meters of height. 

·        Accessibility: Easily accessible from the floors they serve via an accessible means of egress. 

·        Construction: Built with fire-resistant materials. 

·        Ventilation: Open to the outside air on at least one side, often protected by railings, and not locked windows. 

·        Non-Commercial Use: Prohibited from any commercial or residential activity. 

·        Communication: May include communication systems like intercoms or emergency call buttons.

Additionally, two-way communication ( standalone Fire Telephone System to communicate emergency command centre) systems are required in areas of refuge. The exact location of the systems will depend on what is being used as an area of refuge. The system itself, though, needs to allow for communication between the elevator landing and either the fire command center or a central control point that has been approved by the authority having jurisdiction (AHJ). Directions outlining how to use it, how to request help using the system, and written identification of the location all need to be posted next to the two-way communication system. One key component of determining what can be considered an area of refuge is whether or not the building is protected throughout with an automatic, supervised sprinkler system.

Upcoming draft NBC part 4 annex E-4 REFUGE AREA says

E-4.2 Refuge Space/Area

a) Refuge spaces and areas are provided for occupants staging requirements and also enabling assisted evacuation.

The aspect of staging and refuge requirements shall be planned in the building for people with disabilities and ailments, including specific assistance required for certain section of occupants based on their age and other challenges for self-evacuation.

b) Refuge area shall be achieved by adequate planning and consideration of space provided in the lift lobby of fire fighting shaft, enabling the staging for such occupants and further assisted evacuation through fireman lift in the fire fighting shaft. This shall enable these occupants to be assisted evacuated by the lift and further to be brought to exit discharge through the well-planned evacuation strategy through exit passageway on the ground or level of exit discharge. Provision for such staging of the occupants shall be minimum 12m² or 5% of calculated occupants of the floor (served by that firefighting shaft) with a refuge area space of 0.45m² per person in the fire fighting shaft Lift lobby, whichever is higher.

c) Alternatively, refuge area shall be provided in buildings of height more than 24 m. Refuge area provided shall be planned to accommodate the occupants of two consecutive floors (this shall consider occupants of the floor where refuge is provided and occupants of floor above) by considering area of 0.3m² per person for the calculated number of occupants and shall include additionally to accommodate one wheelchair space of an area of 0.9 m2 for every 200 occupants, portion thereof, based on the occupant load served by the area of refuge or a minimum of 15m², whichever is higher, shall be provided as under:

1) The refuge area shall be provided on the periphery of the floor and open to air at least on one side protected with suitable railings.

2) Refuge area(s) shall be provided at/or immediately above 24m and thereafter at every 15m or so. The above refuge area requirement for D-6 occupancy requirement shall however be in accordance with 6.4.2.2.

3) A prominent sign bearing the words 'REFUGE AREA' shall be installed at the entry of the refuge area, having height of letters of minimum 75mm, and also containing information about the location of refuge areas on the floors above and below this floor. The same signage shall also be conspicuously located within the refuge area.

4) Each refuge area shall be ventilated and provided with first aid box, fire extinguishers, public address speaker, fire man talk back, and adequate emergency lighting as well as drinking water facility.

5) Refuge areas shall be approachable from the space they serve by an accessible means of egress.

6) Refuge areas shall connect to firefighting shaft (comprising fireman's lift, lobby and staircase) without having the occupants requiring to return to the building spaces through which travel to the area of refuge occurred.

7) The refuge area shall always be kept clear. No storage of combustible products and materials, electrical and mechanical equipment, etc shall be allowed in such areas.

8) Refuge area shall be provided with adequate drainage facility to maintain efficient storm water disposal.

9) Entire refuge area shall be provided with sprinklers.

10) Where there is a difference in level between connected areas for horizontal exits, ramps of slope not steeper than 1 in 12 shall be provided (and steps should be avoided).

NOTE — Refuge area provided in excess of the requirements shall be counted towards FAR

High rise apartment buildings with apartments having balcony, need not be provided with refuge area; however, apartment buildings without balcony shall provide refuge spaces or area as given above. When refuge areas are preferred over refuge spaces in apartment buildings of height above 60m while having balconies shall be provided at 60m and thereafter at every 30m. The refuge area shall be an area equivalent to 0.3m² per person for accommodating occupants of two consecutive floors, where occupant load shall be derived on basis of 12.5m² of gross floor area and additionally 0.9m² for accommodating wheel chair requirement or shall be 15m², whichever is higher.

Any doors providing access to the area of refuge must have a sign. The area of refuge sign must read “AREA OF REFUGE,” display the international symbol of accessibility, have a nonglare finish, and have letters that contrast with the background. The sign(s) must be illuminated. Tactile signage is also required at each location. Additional signs are required wherever necessary to clearly indicate the direction of travel to an area refuge and at every exit not providing an accessible means of egress. The image below is an example of an area of refuge sign; however, tactile signage would also be required.

Another key aspect of an area of refuge is the presence of wheelchair spaces. Each area of refuge needs to have one wheelchair space that measures 30 inches x 48 inches (760 mm x 1220 mm) for every 200 occupants the area of refuge serves. The wheelchair spaces are not permitted to infringe on the required width of the means of egress for the occupant load served and must never reduce the width to less than 36 inches (915 mm). Each wheelchair space must be accessible without having to pass through more than one adjacent wheelchair space.

Reference:-
CED 46(26992) WC - Draft Code for Comments Only.
NBC 2016 Part 4.
NFPA 101 2024 clause 7.2.4 for more information

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.