Functional Requirements for Water Tender Type 'A' for Fire Brigade Use
1983 Edition

Overview and Scope of the Water Tender Specification

Scope:
This code defines the construction, equipment, and performance standards for Water Tender Type 'A' fire vehicles.

Principal Specifications (Clause 2.2):

Equipment Overview (Appendix A highlights):

• Hose clamps, bandages, straps as per IS 5612 Parts I & II
• Aluminium and wooden extension ladders
• Suction hoses, couplings, and nozzles conforming to IS 903 series
• Portable chemical extinguishers including dry powder and foam types
• Assorted ropes, lamps, and hand tools (axes, spades, crowbars, etc.)
• First aid kit, rubber gloves, asbestos gauntlets

Rounding Instructions:

Values for tests and analyses must follow IS 2-1960 rounding conventions, matching significant figures.

This section ensures adherence to IS 948 regarding design, performance, and equipment for fire brigade water tenders.

Water Tank Capacity and Chassis Criteria Summary per IS 948

1. Water Tank Volume (Clauses 4.2 & 2.1)

• Capacity range specified between 2,700 and 3,600 litres, depending on the chassis model.

2. Tank Fabrication and Mounting (Clause 4.2.1)

• Constructed from mild steel treated to resist corrosion.
• Thickness requirements:
  • Tank shell and baffles (excluding bottom): minimum 3 mm
  • Bottom plate: minimum 4 mm
• Baffle arrangement:
  • Minimum of 2 baffles for 2,700-litre tanks.
  • At least 3 baffles for tanks exceeding 2,700 litres.
  • Positioned to reduce water surge and allow personnel access for cleaning.
• Mounting:
  • Supported on at least three cross members to distribute load and accommodate chassis flex.
  • Secure attachment while allowing removal.

3. Chassis and Performance Parameters (Clause 2.2)

Diagram: Tank Installation and Baffle Layout

flowchart TB
    Tank[Water Tank] --> Baffles{Baffle Count}
    Baffles -->|2 for 2700L| TwoBaffles[Baffle 1 & 2]
    Baffles -->|3 for >2700L| ThreeBaffles[Baffle 1, 2 & 3]
    Tank --> Mounting[Mounted on ≥ 3 Cross Members]
    Mounting --> LoadDist[Load Distribution Across Axles]
    Tank -.-> Corrosion[Anti-Corrosion Mild Steel]

Portable Pump Requirements as per IS 948

Key Details (Clauses 4.3 & 2.2)

• Pump Capacity: 275 liters per minute portable pump complying with IS 942-1982.
• Installation Location: Preferably mounted behind the water tank.
• Mobility Features: Pump frame equipped with two quickly detachable solid-tyred wheels for ease of transport.

Vehicle Performance Requirements (Clause 2.2)

Additional Information

• Detachable wheels enhance pump portability.
• Vehicle braking must meet specified stopping distances.
• Lockers must feature automatic internal lighting and secure, spring-loaded flush doors; side lockers should not have bottom hinges.

flowchart LR
    Vehicle[Water Tender Vehicle] --> Pump[Portable Pump 275 LPM]
    Pump --> Location[Mounted behind tank]
    Pump --> Wheels[Two detachable solid-tyred wheels]
    Vehicle --> Specs[Vehicle Specifications]
    Specs --> GVW[Gross Vehicle Weight ≥ 8500 kg]
    Specs --> MaxSpeed[Max Speed 72 km/h]
    Specs --> Accel[Acceleration 0-50 km/h in ≤ 45s]
    Specs --> Gradient[Gradient Capability 1 in 4]
    Specs --> Braking[Brake distance ≤ 15 m at 48 km/h]

Crew Compartment and Seating Requirements from IS 948

• Capacity and Access (Clause 4.4.1):

  • Enclosed space to accommodate 6 personnel including driver and crew leader.
  • Equipped with two outward-opening doors on each side, hinged at the front.
  • Doors must have catch locks and flush-type handles for secure closure.

• Storage Lockers (Clause 4.4.3):

  • Lockers designed to secure firefighting equipment (except certain specified items).
  • Minimum locker opening height is 600 mm.

Summary Table: Crew Compartment

Diagram: Door and Locker Arrangement

graph LR
    Compartment[Driver & Crew Compartment]
    Compartment --> Doors[Two Doors on Each Side]
    Doors --> Hinges[Outward Hinged, Front Hung]
    Doors --> Locks[Catch Locks & Flush Handles]
    Compartment --> Lockers[Equipment Lockers]
    Lockers --> Height[Minimum 600 mm Opening Height]

Design and Features of Equipment Lockers per IS 948

Dimensions and Construction (Clauses 4.4.2, 4.4.3)

• Locker openings must be no less than 600 mm in height.
• Constructed entirely from metal with adequate rigidity.
• Use of pressed metal sections recommended for strength and lightweight.
• Lockers reinforced to maintain shape and durability.

Door and Lighting Features (Clause 4.4.4)

• Lockers equipped with internal automatic lighting controlled via a meter switch in the cab.
• Doors fitted with flush-fitting spring-loaded locks to prevent inadvertent opening.
• Side locker doors must not be hinged at the bottom to avoid accidental release.

Equipment Storage

• Lockers must securely accommodate all equipment listed in Appendix A, excluding specific items (SI Nos. 1, 2, 26, 44).

Summary Table: Locker Specifications

flowchart LR
    EquipList[Appendix A Equipment] --> Lockers[Lockers]
    Lockers --> Exclusions[Exclude SI Nos. 1, 2, 26, 44]
    Lockers --> Size[≥ 600 mm Opening Height]
    Lockers --> Construction[All-Metal, Reinforced]
    Lockers --> Doors[Spring-Loaded Flush Locks]
    Lockers --> Lighting[Internal Auto Lighting]

Electrical System Specifications under IS 948

Circuitry and Protection (Clause 4.1.2)

• Essential circuits protected by individual fuses.
• Fuses centralized in a common fuse box located inside the driver's cabin.
• Fuse box must include storage for spare fuses.
• Wiring should utilize single-pole wiring for simplicity and safety.

Required Electrical Accessories (Clause 6.2.1)

Notes on Wiring and Fusing

• Fuse ratings must suit circuit loads.
• Single-pole wiring preferred for ease of maintenance.

flowchart LR
    Circuits[Electrical Circuits] --> FuseBox[Fuse Box in Driver's Cab]
    FuseBox --> Fuses[Individual + Spare Fuses]
    Circuits --> Wiring[Single-Pole Wiring]
    Circuits --> Accessories[Electrical Accessories]
    Accessories --> FireBell[Fire Bell]
    Accessories --> Lamps[Head & Fog Lamps]
    Accessories --> Signals[Reversing & Amber Blinkers]
    Accessories --> SirenAndLights[Siren, Search, Spot, Inspection Lights]
    Accessories --> TailAndReflectors[Tail Lamps & Reflectors]
    Accessories --> PA[Public Address System]

Key Vehicle Dimension and Performance Criteria for Water Tender Type 'A' (IS 948)

Notes:

• Water tank capacity increased to 3,600 litres with higher payload diesel chassis.
• Acceleration requirement modified to reflect diesel engine constraints.

Acceleration Calculation:

• Acceleration (a) = Δv / Δt = (50 km/h × 1000/3600 m/s) ÷ 45 s ≈ 0.31 m/s²

graph LR
    Start[Vehicle at Rest] --> Accelerate[Accelerate to 50 km/h in 45s]
    Accelerate --> Cruise[Maintain Max Speed 72 km/h]
    Cruise --> Brake[Brake to Stop within 15m at 48 km/h]
    Brake --> Hold[Hold Position on 1 in 4 Gradient Using Handbrake]

Accessories and Additional Equipment per IS 948 Clause 6.2

Essential Accessories:

• Fire Bell:

  • Diameter: 250 mm
  • Mounted externally, hand-operated, controllable from inside driving cabin.

• Lighting:

  • Two head lamps
  • Two fog lamps
  • Reversing light positioned for driver assistance
  • Amber blinker lights mounted on top of cab
  • Trafficators (illuminated instrument indicators)
  • Two combined stop and tail lamps
  • Rear reflectors for enhanced visibility

• Additional Equipment:

  • Windshield wipers
  • Maintenance tools (excluding chassis tool kit)
  • Battery powered siren
  • Search light with adjustable beam, detachable with tripod and ≥30 m cable
  • Spot light mounted on rear side of cab
  • Inspection lamp with protected plug and control socket
  • Cabin, instrument panel, and locker lighting
  • Optional battery-operated public address system with microphone and external speaker

Important Notes:

• All accessories must comply with height clearance requirements mandated by transport authorities.
• Test results should be rounded as per IS 2-1960.

flowchart LR
    FireBell[Fire Bell (250 mm)] --> Lighting[Lighting Suite]
    Lighting --> HeadLamps[Head Lamps (2)]
    Lighting --> FogLamps[Fog Lamps (2)]
    Lighting --> Reversing[Reversing Light]
    Lighting --> AmberBlinkers[Amber Blinkers]
    Lighting --> Trafficators[Trafficators]
    Lighting --> TailLamps[Tail Lamps (2)]
    Lighting --> Reflectors[Rear Reflectors]
    FireBell --> OtherEquip[Other Equipment]
    OtherEquip --> Wipers[Windshield Wipers]
    OtherEquip --> Tools[Maintenance Tools]
    OtherEquip --> Siren[Siren]
    OtherEquip --> SearchLight[Search Light + Tripod + 30m Cable]
    OtherEquip --> SpotLight[Spot Light]
    OtherEquip --> InspectionLamp[Inspection Lamp]
    OtherEquip --> CabinLights[Cabin & Panel Lighting]
    OtherEquip --> PA[Public Address System]

Workmanship and Finishing Requirements per IS 948

• General Quality (Clause 5.1):

  • All components must demonstrate excellent craftsmanship and possess a smooth, refined finish to ensure durability and aesthetic appeal.

• Corrosion Protection (Clause 3.2):

  • Materials exposed to water or atmosphere must be corrosion-resistant (e.g., stainless steel, aluminum) or treated (galvanized, painted).

• Stability (Clause 4.4.8):

  • The fully loaded vehicle must remain stable when tilted up to 30° from horizontal (excluding crew weight).

Summary Table

Recommendations:

• Employ welding or fastening methods that eliminate sharp or rough edges.
• Apply protective coatings uniformly.
• Maintain dimensional precision for parts fitting and assembly.

flowchart LR
    MaterialChoice[Select Material] --> CorrosionCheck{Is it Corrosion Resistant?}
    CorrosionCheck -->|Yes| UseAsIs[Use Material]
    CorrosionCheck -->|No| TreatSurface[Apply Protective Treatment]
    UseAsIs & TreatSurface --> Quality[Ensure Good Workmanship]
    Quality --> Finish[Smooth, Streamlined Finish]
    Finish --> FinalInspect[Conduct Final Inspection]

Compliance with Legal and Regulatory Standards as per IS 948

1. Vehicle Performance and Dimensions (Clause 2.2):

   • Gross Vehicle Mass: Minimum 8,500 kg including crew, water, and equipment.
   • Maximum Speed (fully loaded): 72 km/h on flat terrain.
   • Acceleration: 0 to 50 km/h within 45 seconds when fully loaded.
   • Gradient Capability: Ability to start and move on a 1:4 slope.
   • Braking:
     • Foot brake must stop the vehicle within 15 m from 48 km/h on dry level surface.
     • Hand brake must hold the vehicle on a 1:4 gradient while in neutral gear.
   • Dimensions:

     Parameter	Maximum/Minimum Limit
     Wheelbase	≤ 4.30 m
     Turning Circle Diameter	≤ 20 m
     Ground Clearance	≥ 23 cm
     Overall Width	≤ 2.50 m

2. Markings and Equipment (Clause 22.5 & Appendix A):

   • Hose fittings, clamps, bandages, and straps per relevant IS codes (IS 5612 Parts I & II).
   • Fire hoses, nozzles, and suction heads compliant with IS 903 and IS 1904.
   • Essential tools including hydraulic jacks (7.5 tonnes capacity), fire hooks, gloves (IS 4770), axes (IS 703), pick axes (IS 273), crowbars (IS 704), etc.
   • Safety and operation devices such as lamps, dry powder and foam extinguishers (IS 2171, IS 933), and ropes (IS 1084).

3. Statutory Compliance:

   • All equipment and vehicle dimensions must conform to Transport Authority height clearance regulations.
   • Test values and results must be rounded as per IS 2-1960.

Summary Table: Critical Vehicle Specifications