Depot > Planning and Design Standards – Resilient E-bus Ecosystem

1. Fleet

2. Depot

3. Charging Infrastructure

4. Operating Environment

Planning and Design Standards

This section presents the planning and recommendation framework for safe, resilient, and efficient e-bus depot and terminal development. It addresses key risk dimensions electrical, thermal, water, cyber, structural, and occupational safety and applies to both greenfield and brownfield depots. Emphasis is placed on preventive planning, robust engineering design, standard operating procedures, and workforce preparedness to ensure safety, asset protection, and service continuity. The recommendations respond to the rapid scale-up of e-bus adoption by public bus agency and the parallel need to both retrofit existing depots and develop new depot facilities, which are categorised as brownfield and greenfield depots, respectively.

QnA

Q1. A State Transport Undertaking (STU) is planning a new greenfield e-bus depot expected to expand from 60 to 120 buses over the next 5 years. During site selection, which action best supports electrical safety and service continuity in the pre-disaster phase?

Selecting a low-cost site far from the grid and relying on diesel generators Prioritising proximity to an existing high-voltage grid with spare capacity Installing overhead HT lines across the depot to save trenching costs Planning a single power feed to reduce capital expenditure

Q2. During operations, an e-bus depot manager notices rising temperatures near charging bays during peak summer months. Which pre-disaster planning measure would most effectively reduce the risk of thermal runaway and fire spread?

Increasing charging speed to reduce dwell time Parking all buses in a single large open bay Compartmentalising e-bus parking with fire barriers and quarantine zones Relocating administrative offices away from the depot

Q3. An STU is inducting drivers transitioning from ICE buses to e-buses. Which training focus is most critical from a pre-disaster safety perspective?

Maximising acceleration to maintain schedules Understanding regenerative braking and safe energy-efficient driving Avoiding use of emergency shutdown systems Reducing PPE usage to improve driving comfort

Q4. While procuring charging infrastructure and planning a brownfield depot conversion, an STU wants to minimise technology obsolescence and safety risks. Which requirement should be included in OEM contracts?

One-time hardware installation with no future upgrades Vendor-agnostic systems with no software controls Periodic software and hardware updates with long-term vendor support Manual charging systems only to reduce cyber risk

ELECTRICAL SAFETY

Planning Recommendations

Effective implementation of electrical safety requires targeted mitigation actions by relevant stakeholder, as outlined in the following table to support enforcement and ensure compliance.

S.No.

Activities

Responsibility

Prioritise Grid Proximity

Avoid Overhead Lines

Safely Locate Transformer and Substations

Provide Power Redundancy

Establish safe boundaries to minimise risk of electrical injuries

Prioritise Grid Proximity: For both brownfield and greenfield e-bus depot / terminals, prioritise the site near an existing high-voltage infrastructure / grids, that has adequate capacity to cater to the requirement of existing fleet as well future expansions and upgrades of the e-bus depot/ terminal.
Avoid Overhead Lines: During site selection, ensure that no high-tension towers or overhead cables pass over or through the depot/ terminal premises to minimise safety risks.
Safely Locate Transformer and Substations: Locate the transformer and the substations in designated safe area in compliance with applicable regulations. Layout should account for transformer’s capacity, safety clearance, cable trenching routes and contingency provisioning (e.g. dual feed).
Provide Power Redundancy: Create redundancy by way of providing duplicate or separate electricity cables to ensure at least half of the fleet remaining operational during disruptions.
Establish safe boundaries to minimise risk of electrical injuries: Clearly defined safety boundaries shall be established around electrical equipment (such as Compact Sub Station, Switchgear, Ring Main Unit, Transformer, charger power cabinets, etc) to physically and procedurally separate personnel from electrical hazards during both normal operation and maintenance. To address these risks, NFPA 70E and IEEE 1584 define three critical electrical safety boundaries as follows:
- Restricted Approach Boundary: Allows only qualified personnel with insulated tools and PPE. This boundary may be clearly demarcated using red floor markings or painted zones.

- Limited Approach Boundary: Prevents unqualified personnel from entering zones near energized parts. This boundary may be clearly demarcated using orange floor marking.
- Arc-Flash Boundary: Defines the distance at which arc-flash energy can cause second-degree burns, requiring full arc-rated PPE. This boundary may be clearly demarcated using yellow or dashed line floor markings or painted zones.

Recommended Standards

The following standards shall be incorporated in the planning and design of e-bus depot and terminal by the Civil and Electrical Engineering team of the public bus transport agencies, with involvement of OEMs wherever they are part of the e-bus depot planning and design process.

High voltage and fire safety systems should include battery isolation units, high-tension earthing grids, temperature and smoke detection sensors designed in accordance with NBC 2016 and IEC 60364.

Design layout is recommended to:

Clearly segregate High-Voltage (HV) and Low-Voltage (LV) panels

Ensure unobstructed access paths to isolation switches and control panels

Utilize fire-retardant cable trays and armoured High Voltage cables for fire and arc flash safety

All depot/ terminal switchgear and control panels are recommended to:

Use arc-rated switchgear with internal arc containment as per IEEE 1584 guidelines

Have IP54 or higher-rated enclosures for indoor panels to ensure dust and moisture protection

Include type-tested LT/HT panels with interlocks for operator safety & Visual indicators for circuit status (ON/OFF/Trip)
Clearly label Circuit identification; Hazard signage (e.g., “Danger – 415V” or “Arc Flash Risk”)

Standard Recommendation

All Electrical Infrastructure in E-Bus Depot/ Terminal must comply:

Code of practice for Earthing: IS3043
Electrical Installation in building: IS732/IEC 60634
Guide for Performing Arc Flash Hazard Calculations: IEEE 1584
IP 54+ Protection: For all indoor electrical panels/switchgear

THERMAL SAFETY

Planning Recommendations

Successful thermal safety implementation depends on targeted mitigation measures by relevant stakeholders, as detailed in the table below to enable effective enforcement and compliance.

S.No.

Activities

Responsibility

Compartmentalise E-Bus Parking

Fire Risk Zoning in depots

Early Detection, Suppression & Firewater Management:

Provide For Battery Storage

Use Fire Retardants Materials

Limit Toxic Materials

Maintain Repair zone Cleanliness

Ensure adequate and safe ventilation

Restrict Repair zone Access

10.

Control Dust Levels

11.

Provide Shading

12.

Application of Cool Roof Treatment

Compartmentalise E-Bus Parking: Provide compartmentalisation for parking of e-buses along with fire-barriers or fire-safe curtains and designated quarantines zones to effectively mitigate fire risks and minimise disruption in operations.
Fire Risk Zoning in depots: All depots while planning or in the existing construction shall be reclassified into fire risk zones to minimise safety risks.
- High-risk zones: charging bays, substations, transformers
- Moderate-risk zones: workshops, maintenance bays
- Low risk / safe occupancy zones: offices, control rooms, staff facilities
Early Detection, Suppression & Firewater Management: The early detection system (Heat, smoke) is only present in admin building. The early detection and suppression system can be further improved using following measures:
- Thermal Imaging: Infrared & thermal imaging helps in detecting hotspots & anomalies in battery temperature.
- Arc Fault Detection Device: Detect dangerous electrical arcs caused by loose connections or damaged cables, and electrical fires.
- Surge Protection Devices (SPD): SPDs protect chargers and electrical systems from voltage spikes due to lightning, grid fluctuations, or switching surges. They prevent damage to sensitive power electronics, reduce downtime, and improve overall system reliability.
- Firewater drainage shall be reviewed to ensure: No backflow into electrical rooms and no pooling near chargers or substations
Provide Battery Storage: A dedicated and secure space, preferably segregated from parked e-buses, staff areas, and other core depot facilities, should be provided for battery storage, given the significant fire, explosion, and chemical hazards associated with batteries.
Use Fire Retardants Materials: Use materials with a fire-retardant coating wherever deemed necessary.
Limit Toxic Materials: Limit the amount of toxic and hot gases generating materials in an e-bus depots/ terminals.
Maintain Repair Zone Cleanliness: Maintain high voltage power battery repair sites clean, dry, spark free and free of greases, stains and metal debris. Avoid locating the repair zones near vehicle cleaning area and use movable partition if necessary.
Ensure adequate and safe ventilation: Ensure adequate ventilation (indoor) or open-air setting (outdoor), with clear signage prohibiting fire, water and high-voltage hazards.
Restrict Repair zone Access: Allow access to authorized repair personnel only.
Control Dust Levels: Apply dust control treatment on floors or other surfaces to extend equipment life and reduce arc flash risk.
Provide Shading: Use shading (trees or canopy structure) to mitigate the heat stress and maintain microclimate.
Application of Cool Roof Treatment: Apply cool roof treatments or shading devices to minimise direct solar heat exposure of the depot roof and reduce overall heat buildup.

Recommended Standards

The following standards shall be incorporated in the planning and design of e-bus depot and terminal by the Civil and Electrical Engineering team of the public bus transport agencies, with involvement of OEMs wherever they are part of the e-bus depot planning and design process.

E-bus parking areas be compartmentalized with fire protect barriers to reduce the risk of fire spread. For example, in a depot with 100 e-buses, the parking layout be divided into four zones compartments each accommodating 25 e-buses. The layout may be customised to meet local circumstances and safety issues.
A minimum 4m gap is advisable between compartments to allow access for fire trucks during emergencies.
Install high-pressure water mist system as a firefighting system at e-bus depot/ terminal to help reduce the intensity of thermal radiation from flames to the surroundings17.
Fire risk mitigation design is recommended to account for ventilation effects, as they impact suppression zones, water storage volumes, and potential delay in fire control that may increase losses.
Install infrared and thermal imaging technologies that are effective in detecting battery hotspots and temperature anomalies. When integrated with building automation systems, they enable real-time monitoring and early detection of potential fire risks.
The most significant risk related to working with e-buses is “arc flash” and “thermal runaway” which underlines the clear need to design out some risks and create standard operating procedures (SOPs).
Establish guidelines on fire safety and evacuation along with clearly defined emergency routes, and designated refuge areas within depots/ terminal premises.

Standard Recommendation

Fire Safety Guidelines: NBC 2016: Part IV for fire protection and relevant local byelaws, ISI codes such as IS15105:2002, IS:5312. IS:908 and IS:2190. IS:5290,
Fire Detection and Alarm System: IS 2189:2008 for the design and installation of FDAS and NFPA 72 (International Code) on fire alarm and signalling.
Installation of Sprinkler System: NFPA 13 (International Code)
CEN and Standards Australia governing the design, installation, and maintenance of water mist fire protection system.

WATER PROTECTION

Planning Recommendations

Ensuring water protection requires clearly defined mitigation actions by responsible stakeholders, as outlined in the table below to facilitate enforcement and ensure compliance.

S.No.

Activities

Responsibility

Avoid Sensitive Land Use

Access Flood Hazards

Mitigating Low-Lying Risk

Design Surface Drainage

Implement Detention Measures

Provide Emergency Dewatering System

Build Flood-Resilient Structure

Avoid Sensitive Land Use: Avoid depot site location in close proximity to residential areas and other non-conforming land uses for depot activities.
Access Flood Hazards: Conduct hydrological studies based on a 1 in 100 years return period or assess flood hazards.
Mitigating Low-Lying Risk: If the yard level of a depot/ terminal is lower than the surrounding roads or land, it faces a high risk of flooding which may pose significant risk due to presence of electrical infrastructure. Following measures are recommended to avoid such vulnerabilities:
- If the brownfield depot/ terminal is in low- lying as above or located in flood prone areas, then raise the depot/ terminal ground level to at least the flood safety heights.
- For greenfield e-bus depot/ terminal, select the site above historical flood levels, avoid locating the depot site in low-lying or floodplain zones.
Design Surface Drainage: Conduct a detailed contour survey to design proper grading and slope for surface drainage. Ensure that the location of any new depot/ terminal is not near a steep hill or in a flood prone area. Provision of waterproofing membranes, and underground drainage systems to prevent water accumulation are also recommended.
Implement Detention Measures: Construct micro-detention reservoirs, rainwater harvesting pits and install porous pavements to prevent water coming inside the depot.
Provide Emergency Dewatering System: Depots/ terminal advised to be equipped with water pumps and sandbags to prevent water accumulation and enable quick drainage.
Build Flood-Resilient Structure: Design and construct flood-resilient battery storage areas, charging bays, and electrical rooms based on regional flood maps and hydrological assessment.

Recommended Standards

Maintain the plinth level of the depot/ terminal and charging infrastructure at least 0.5 to 1.0 meters above the highest recorded flood level (HFL). Alternatively, charging infrastructure may be installed on moveable platforms that can be adjustable as required.

Storm water and drainage:
- Provide stormwater drains or RCC open channels along driveways.
- Include grated trench drains at vehicle entry/exit points.
- Ensure optimal drainage, of minimum 1%-2% for hardscapes (bus driveways) to natural drainage points.

Incorporate emergency evacuation lanes and designated flood-safe parking zones within the of e-bus depot/ terminal design. In case of emergency, Asset evacuation SoP is to be activated upon early warning alerts from IMD or local authorities.

Install flood resilience measures such as pumps, rainwater harvesting structure, underground drainage pipes to drain out excess runoff in the depot area.

Install moisture sensors, water alarms, and water level indicators near critical electrical and mechanical zones.

Equip depots with sump pumps, water diversion channels, and emergency diesel pump systems to rapidly drain water from electrical areas.
Store maintenance equipment, PPEs, and battery tools in elevated waterproof storage units.

Standard Recommendation

Integrate auto cut-off systems to isolate power in case of water intrusion: AIS-138 Part 2, Clause 7.0.

CYBER SECURITY

Planning Recommendations

Effective implementation of cyber security requires targeted mitigation actions by relevant stakeholder, as outlined in the following table to support enforcement and ensure compliance.

S.No.

Activities

Responsibility

Develop Cybersecurity Protocols

Secure Grid Communication

Train Depot Personnel

Restrict Zone Access

Update Software Regularly

Implement Backup Systems

Enforce Access Controls

Maintain Security Scanning

Develop Cybersecurity Protocols: Establish depot/ terminal specific cybersecurity protocols.
Secure Grid Communication: Use Open Automated demand response (OpenADR) with encrypted communication for grid interaction.
Train Depot Personnel: Train depot/ terminal personnel on cyber hygiene, cyber security and incident response.
Restrict Zone Access: Restrict access to critical zones within the depot/ terminal.
Update Software Regularly: Ensure all software systems are updated at defined intervals.
Implement Backup Systems: Implement robust backup systems for critical depot/ terminal operations to ensure continuity during cyber incidents or system failure.
Enforce Access Controls: Maintain strong password and multifactor authentication for important depot/ terminal access.
Maintain Security Scanning: Maintain latest scanning software with preset scanning frequency for stored data and pre-entry scanning of all incoming data.

STRUCTURAL SAFETY

Planning Recommendations

Successful implementation of structural safety requires targeted mitigation actions by relevant stakeholder, as outlined in the following table to support enforcement and ensure compliance.

S.No.

Activities

Responsibility

Designated Earthquake Zones

Seismic Wind Design

Anchor Against Debris

Provide Reinforced Shelters

Enhance Pedestrian Safety within E-Bus Depot

Designated Earthquake Zones: While planning the site, earmark designated open area as an earthquake-safe zone, allowing staff and crew to evacuate safely in the event of high seismic activity. Provide and clearly mark earthquake safe spaces inside all buildings of the depot/ terminal to enable safe positioning of staff in the event of evacuation time being too short.
Seismic Wind Design: Design depots/ terminal and charging stations to withstand high wind speeds and minor seismic activity.
Anchor Against Debris: Use wind-anchored enclosures and protective systems to resist flying debris during high-wind or storm events.
Provide Reinforced Shelters: Provide indoor bus storage or shelters with reinforced canopies and anchor systems.
Enhance Pedestrian Safety within E-Bus Depot: As e-buses generate significantly lower noise levels than ICE vehicles, provide clearly marked pedestrian zones within the e-bus depot with all-weather visibility, physically separated from driving lanes, high-voltage zones, and areas requiring personal protective equipment, to reduce collision risks.

Recommended Standards

The following standards shall be incorporated in the planning and design of e-bus depot and terminal by the Civil and Electrical Engineering team of the public bus transport agencies, with involvement of OEMs wherever they are part of the e-bus depot planning and design process.

Leverage existing building bye laws and recommended practices on earthquake and cyclone resistance while designing greenfield depots/ terminals for e-buses, ensuring better preparedness and sustainability.
Bus parking and movement:
- Design bus parking with elevated hardstands and reverse-slope-free entries.
- Use reflective markings and signage to guide buses during low visibility.
- Charger Layout: Charger pedestals may follow the design standard (1 m × 1 m, 450-600 mm height) with at least 1 m clearance on all sides. Maintain 1.5–2 m distance from walls, and 1.0–1.5 m between adjacent chargers. Refer to the illustrations for visual guidance on these dimensions.
- Minimum space width for parking a 2.6 m wide bus be 3.6 m and that for charging an e-bus may be 4.6mtrs.
- A 45-degree parking layout with over 12m turning radius allows easy manoeuvring for standard sized buses.
- Maintain a minimum clearance of 2 meters space between the bus and the charging infrastructure while parking an e-bus for charging.
Install floor-level stopping guides to help drivers align accurately to designated space and to prevent collision between e-buses and charging infrastructure.
Implement real-time CCTV surveillance within the depot/ terminal and at other key locations.
Restrict entry via biometric access, ID badging, and automated gates during high-risk periods.
Install guided parking systems and protective infrastructure in high-risk parking zones.
Use color-coded curbing for safe navigation.
Reduce speed limits within depot premises may be introduced using geofencing and onboard speed limiters.

COMMON SAFETY MEASURES

Effective implementation of common safety measures requires targeted mitigation actions by relevant stakeholder, as outlined in the following table to support enforcement and ensure compliance.

S.No.

Activities

Responsibility

Optimise Depot Layout

Entry-Exit to the depot

Account for additional infrastructure space

Plan Compact Infrastructure

Conduct Risk Assessment

Ensure Route Proximity

Zone Depot Areas

Accessible Shutdown Buttons

Provide Quarantine Space

10.

Allocate Charging Space

11.

Prevent Obsolescence Risks

12.

Approval and Sanctions Required

13.

Plug Based / Pantograph Charging System at Depot

14.

Manpower Safety Protection

15.

Occupational Safety

16.

E-bus washing area

17.

Repair and Maintenance area

18.

Quarantine area for Damaged buses / Equipment

19.

Battery Storage rooms

20.

Safety Procedures at Maintenance area

21.

Waste and Battery Management

Planning Recommendations

Optimise Depot Layout: Create depot/ terminal layout plan to facilitate friction-free bus movements during entry-exit for parking of e-buses, workshops for repairs and the charging infrastructure for charging preventing congestion during peak hours.
Entry-Exit to the depot:
- Plan sperate entry and exit gates to aid unidirectional movement of buses that can streamline the movement.
- Locate entry-exit gates in a manner that minimises traffic disturbance outside the depot.
- Install outdoor day/night CCTV cameras with IP 65 protection, along with perimeter access controls, and adequate lighting systems to enhance physical security and ensure uninterrupted operations, especially in depots with 24×7 fleet movements.
Account for additional infrastructure space: E-bus depot requires more space to accommodate additional infrastructure such as cabling, chargers, and transformer.Provide additional depot space or reduce the capacity of the depot whileconverting an existing ICE buses depot to e-buses depot.
Plan Compact Infrastructure: In space-constrained depots, efficient layout planning besides compact infrastructure provision are essential to minimize impacts, though fleet size reduction or relocation of part of the fleet will still be necessary.
Conduct Risk Assessment: Undertake a detailed risk assessment for both brownfield and greenfield depots to identify and mitigate site-specific operational and safety risks.
Ensure Route Proximity: For greenfield e-bus depot, ensure proximity to bus routes and access via well paved roads with a minimum 15m right of way at entrance and exists, as per the MoHUA guidelines “Manual for planning, design & implementation of city bus depot, 2020”, to reduce long term maintenance issues.
Zone Depot Areas: Divide the depot into functional zones (such as high-risk zones, safe parking zones, and maintenance zones) to enable targeted disaster risk management and operational control.
Accessible Shutdown Buttons: Locate all the emergency shutdown button at accessible locations.
Provide Quarantine Space: Plan for provision of segregated space to park / quarantine e-buses involved in collisions and or in thermal runaways. Provide at least 2-4 meters space between quarantined buses and preferably with intervening fire screens.
Allocate Charging Space: Provide for adequate space for charging station based on the number of chargers planned, including required clearances between buses and charging infrastructure. Additional space should also be allocated for power supply substations and transformers, with provision for future scalability to accommodate additional chargers or system upgrades as the fleet expands.
Prevent Obsolescence Risks: To safeguard against technological obsolescence, depot management and technology controller are advised to update of software and relevant hardware periodically and maintaining vendor agreement for continued support.

Approval and Sanctions Required:

Approval and sanctions required for both brownfield depot and greenfield depot are as follows:

Strengthen Approval Process: The current e-bus depot approval process is followed for conventional bus depot norms and lacks EV-specific safety measures, hazard risks, and disaster resilience considerations. Obtain necessary additional approvals from agencies such as the Fire Fighting Department, DISCOMs, Disaster Management Authorities, Explosives Department and Electrical Inspectorates to address fire safety, chemical spillage and explosions from traction batteries, high-voltage electricity related risks, hazard zoning, and emergency preparedness etc. Integrating these clearances will ensure safer, more resilient depot operations.
Ensure Regulatory Compliance: All required clearances should comply with applicable electrical regulations including the National Electrical Code (NEC) and International Electrochemical Commission (IEC) standards, as well as relevant fire safety codes, such as those issued by National Fire Protection Association (NFPA) and European Standard (EN) 50620 for EV infrastructure or any other relevant and accepted codes by the authority.
Mandate Design Audit: In addition to the above approvals when converting a brownfield depot into an e-bus depot or constructing a new green field facility, the layout is recommended to undergo a third-party design audit overseen by the Civil & Infrastructure department of the STU/ ULB during construction of the depot/ terminal.
Conduct Safety Audits: A designated safety officer is advised to ensure annual third-party safety audits of the e-bus depot or terminal to verify continued compliance, identify emerging risks, and strengthen overall safety performance.

Plug Based / Pantograph Charging System at Depot

Canopy charging system (plug-in or pantograph): Built into overhead roofs are space efficient, minimises civil works and are suitable for flood prone areas as well.
Automated Overhead Charging: The charging Infrastructure is installed at a height and the charging takes place automatically. Thus, a revised parking bay to maximise the existing surface for the buses.

Manpower Safety Protection

Authorised Trained Technicians: Only trained and certified technicians can perform maintenance on high-voltage components.
Buddy System Requirement: Workers should never work alone on or near high-voltage systems. A colleague with equal or greater training should be present.
Mandatory PPE Usage: All personnel are required to use appropriate PPE specifically rated for the high-voltage levels present.
- Insulated gloves: Use rubber gloves with the correct voltage rating.
- Face shield: Protect against arc flash hazards.
- Safety helmet: For head protection.
- Electrical safety shoes: Rated for electrical hazards.
- Flame-resistant (FR) clothing: Minimises burn injuries.

Non-conductive barriers: Use rubber insulation mats and other insulated barriers to protect against electrical contact.
Decommissioning Procedure: Before any maintenance or service work begins, a strict decommissioning procedure to be followed from preventing serious injuries or death.
- Isolate the vehicle:Ensure the e-bus is not connected to the charging cable.
- Turn off ignition:Switch off the vehicle’s ignition.
- Perform lockout/tagout:Implement lockout/tagout procedures to prevent accidental re-energization.
- Disconnect auxiliary battery:Disconnect the 12V or 24V auxiliary battery and insulate the terminals.
- Remove the service plug:Use the manual service disconnect, often a plug or switch, to break the circuit within the main HV battery pack.
- Discharge the system:Wait for the time specified by the manufacturer (often 10 minutes) for the system to safely discharge. The vehicle’s internal systems may automatically discharge to a safe voltage level below 60V DC.
- Verify zero voltage:Before touching any HV components, use a rated voltage detector to confirm that the system is at zero potential (0V). Test the detector on a known live source first to ensure it is working correctly.
- Ground the work area:For additional protection against accidental re-energising, grounds should be placed on both sides of the work area.

Occupational Safety

Defined Responsibility for Safety Protocols: Fix responsibility for adhering to safety protocols, during operations, maintenance, cleaning of buses and the charging process using charging infrastructure, on the depot/ terminal staff, charging infrastructure staff and the bus crew.
Emergency power isolation: In the event of electrical hazards or loss of control, the immediately isolated and shut off of power source is recommended. Install emergency shutdown mechanisms at high-risk areas, such as near transformers and inspection or repair stations.
Inclusive emergency alerting: It is essential to ensure that all depot staff, including individuals with disabilities, are promptly alerted during emergencies. To enhance accessibility, install various alerting systems such as non-auditory alarms like flashing beacons, which provide visual or sensory alerts for persons with disabilities.
Heatwave worker protection: During heatwaves provide shaded rest zones, hydration stations and regular breaks, along with installing industrial fans or evaporative coolers in workspace.
Occupational safety standards: Additionally, follow British Standards, OHSAS 18001:2007 (Occupational Health and Safety Assessment Standard) as reference standards to ensure overall health and safety of depot staff.

E-Bus maintenance:

E-bus washing area:
- Avoid using direct water spray, hoses or pressure washes on electrical compartments and components. Clean connector points with a dry cloth to remove dirt.
- Develop SOP for e-bus washing to guide staff on safe practices and minimise human error or accidental exposure to electrical components.
- Physical barriers, designated pathways, or clearly marked zones between washing and charging areas in an e-bus depot help prevent water or cleaning agent from damaging the charging equipment or creating safety hazards.
- Ensure that high voltage components of e-buses are provided with ingress protection degree IP 65 or higher.
Repair and Maintenance area:
- Equip engineering bays with smaller or lower-power charging points to maintain vehicle battery levels during repair and maintenance activities.
- Ensure that all charging infrastructure is serviced and maintained only by certified electricians who are trained and qualified to handle high-voltage equipment.
Quarantine area for Damaged buses / Equipment:
- In case of a damaged e-bus or electric vehicle supply equipment (EVSE), a physically separated room or enclosed area with firewalls be provided. This segregation is essential to minimize the risk of battery fires or thermal runaway incidents.
- In case of scarce spaces, install firewalls or other features between the damaged buses.
Battery Storage rooms:
- The battery storage room is recommended to have humidity control, temperature control and adequately ventilated and the whole building is required to be fire resistant proof and should have a structural isolation is needed.
- Equip battery storage spaces in the depot with fire suppression systems, and train staff to respond to fire emergencies and to adhere to battery-specific safety protocols.
- Provide storage space for new battery packs depending upon frequency of replacement of retired battery packs and the cycle time to acquire new batteries e.g. a stock of 4-5 battery packs per 40 e-buses be retained in the depot and an additional space for storge of unserviceable battery packs or retired battery packs be assessed and additional space to be provided for in design of depot.
- The OEM to undertake disposal of EV batteries. The OEM/ Operator to immediately evacuate damaged batteries from premises and retired batteries shall be collected within a week.
- The space is advised to be adequately ventilated, with batteries stored away from moisture and excessive heat, and in compliance with the design standards specified by the battery supplier.
- As per “Manual for Planning, Design and Implementation of City Bus Depots” notified by MoHUA, 15-30 air changes per hour are required for a high fume area such as battery room to prevent the room from overheating.
- A Category E fire alarm system be installed to address electrical fire risks common in industrial and commercial settings. This requires specialized detection and suppression systems, such as linear heat sensing cables, smoke detectors, fire detection and suppression systems (FDSS) and other specialised detection and suppression system for electrical hazards.
Safety Procedures at Maintenance area:
- All electrical and battery – related maintenance be carried out by specialised, trained and certified staff.
- Staff performing electrical maintenance activities is required to wear appropriate PPE, including insulating gloves and protective screens.
- Train engineering teams on the safe handling and isolation of high-voltage systems. Develop and implement a clear SOP for safety procedures, including emergency response protocols.
- Re-train drivers to adapt to e-buses, focussing on safety and energy efficient driving techniques particularly related to acceleration and braking. As part of the highlight the fact that regenerative braking reduces brake pad wear and improves energy efficiency.
Waste and Battery Management:
- Designation of battery recycling zones and secure storage for spent lithium-ion batteries as per the updated CPCB guidelines.
- Systems for wastewater reuse such as Effluent Treatment Plant (ETP) for bus washing and other activities, along with solid waste segregation and Sewage Treatment Plant (STP) should be integrated into depot operations.

REFERENCE E-BUS DEPOT LAYOUT

Based on the planning and design recommendations outlined above, a reference e-bus depot layout has been developed to demonstrate the practical application of safety, resilience, and operational principles. The conceptual layout is designed to accommodate a fleet of 100 e-buses on approximately 5.5 acres of land, along with around 25 charging stations, and incorporates dedicated isolation zones for damaged e-buses and fire-safe areas for the storage, repair, and handling of battery packs (new, repairable, and repaired). The depot design promotes compartmentalised parking preferably in clusters of 24–25 buses with adequate separation (approximately 4–5 metres) and fire screens between compartments to limit fire spread and ensure operational continuity. A unidirectional internal circulation pattern is proposed to minimise conflict points and reduce accident risks. While non-e-bus-specific facilities follow conventional depot design standards, additional space and safety provisions are incorporated for e-bus-specific requirements, including charging zones, handling of damaged vehicles, end-of-life battery storage and disposal, and opportunity charging at terminals. Overall, the reference layout emphasises climate-resilient, structurally robust, and scalable civil infrastructure, providing a safe, efficient, and future-ready template to support the long-term sustainability and reliability of electric bus ecosystem services.

The following planning and design standards shall be incorporated in the planning and design of e-bus depot by the Civil and Electrical Engineering team of the public bus agencies, with involvement of OEMs wherever they are part of the e-bus depot planning and design process.

This comprehensive conceptual design layout ensures operational efficiency, safety, and resilience, enabling smooth functioning of the EBES. In particular, a well-planned internal bus‑circulation layout, with appropriately located activities and facilities, reduces manoeuvring time and enhances operational efficiency, while simultaneously ensuring compliance with fire, electrical, and overall operational safety standards.