Firefighting vehicles and equipment - symbols for operator controls and other display
2006 Edition

Overview of IS 15682 Scope and Symbol Classification

Scope (Clause 2.1):
Specifies geometric shapes and symbols for the following categories:

• Frame, Engine, and Chassis
• Electrical Circuits
• Tanks and Piping
• Pressure Vessels
• Aerial Appliances
• Other Miscellaneous Symbols

Representative Tables of Symbols

Sample Symbols for Frame, Engine, and Chassis (Clause 3.1)

Notes:

• Symbols visually represent operational states or components for clarity.
• Used for standardizing diagrams and controls on firefighting apparatus.
• Detailed symbol illustrations and instructions are given in respective clauses.

flowchart TD
    A[Scope] --> B[Frame, Engine & Chassis]
    A --> C[Tanks & Piping]
    A --> D[Electrical Circuits]
    A --> E[Pressure Vessels]
    A --> F[Aerial Appliances]
    A --> G[Miscellaneous]

    B --> B1[Engine Start/Stop]
    B --> B2[Rotational Speed (N_min)]
    B --> B3[Jacking Systems]
    B --> B4[Axle Locking Mechanism]

    C --> C1[Water Tank Fill/Drain]
    C --> C2[Foam Concentrate Fill/Drain]

IS 15682: Essential Requirements for Symbols and Designations

This standard defines graphical symbols for various firefighting system components:

Tank and Piping Symbols (Clause 3.5)

Fire Pump Symbols (Clause 3.4)

Miscellaneous Symbols (Clause 3.8)

Important Notes:

• Focus lies on symbol assignments rather than numerical formulas.
• For structural and hydraulic calculations, refer to IS codes such as IS 456, IS 800, and other hydraulic design standards.

IS 15682: Standardized Symbols for Firefighting Vehicle Controls and Displays

Key Highlights:

• Consistent Symbol Scale (Clause 2.4): All graphical symbols must maintain uniform relative scaling consistent with the drawing scale, ensuring clarity.

• Symbol Categories (Clause 3): Symbols cover controls including:

  • Water pump operations
  • Foam system valves
  • Ladder controls
  • Sirens and lighting
  • Other firefighting equipment interfaces

Example Symbol Usage:

Best Practices:

• Employ standard symbols to avoid ambiguity during emergencies.
• Ensure symbols are legible and uniformly sized across drawings.
• Refer to annexures in IS 15682 for precise symbol designs.

flowchart LR
    A[Firefighting Vehicle] --> B[Operator Controls]
    B --> C{Control Types}
    C --> D[Water Pump]
    C --> E[Foam System]
    C --> F[Ladder]
    C --> G[Siren & Lights]

For detailed symbol shapes and dimensions, consult the complete IS 15682 standard.

IS 15682 - Frame, Engine, and Chassis Symbols (Clause 3.1)

This section specifies symbolic indicators for frame, engine, and chassis related controls and components:

Notes:

• Rotational speed (N_min) is a critical engine/chassis parameter.
• Symbols for engine start/stop, jacking, and axle locking help in schematic standardization.
• Continuous adjustments may be either rotational or linear.

Engineering Context:

• Frame design must withstand dynamic stresses.
• Monitoring engine rotational speed ensures operational safety.
• Jacks and axle locks provide stability during operations or maintenance.

For detailed structural formulas, consult IS 800 (steel) or IS 456 (concrete) codes.

graph LR
  EngineStart --> EngineStop
  EngineStart --> RotationalSpeed[N_min]
  RotationalSpeed --> AuxiliaryCooler
  JackingSystems --> VehicleStabilized
  VehicleStabilized --> HouseJacks[Î]
  HouseJacks --> AxleLockOn
  HouseJacks --> AxleLockOff

This diagram illustrates the relationships among key symbols.

IS 15682 - Electrical Circuit Symbols (Clause 3.2 and 3.8)

Electrical Circuit Designations (Clause 3.2, Table 3.2)

Miscellaneous Electrical Symbols (Clause 3.8, Table 3.8)

Summary:

• Symbols provide a unified visual language for electrical and warning devices.
• Standardization aids in quick identification and operation under emergency conditions.

IS 15682: Firefighting Expellant Symbols (Clause 3.3)

Expellant Types and their Symbols (Table 3.3)

Additional Details:

• Water serves as the primary extinguishing agent.
• Foam concentrate and premix solutions are used for foam-based suppression.
• Powder is commonly employed in dry chemical systems.

Typical Foam Solution Preparation Formula:

[ Q_f = C \times Q_w ] Where:

• (Q_f): Foam concentrate flow rate
• (C): Foam concentration ratio (e.g., 0.03 for 3%)
• (Q_w): Water flow rate

Flow Overview:

flowchart LR
    Water -->|Mixed with| Foam_Concentrate
    Foam_Concentrate --> Pre_mix_Solution
    Pre_mix_Solution -->|Delivered to| Firefighting_System
    Powder -->|Direct Discharge| Firefighting_System

Refer to IS 15682 Tables 3.4, 3.5, and 3.6 for detailed fire pump, tank, piping, and pressure vessel symbols.

IS 15682 - Fire Pump Symbols and Details (Clause 3.4)

Fire Pump Types (Table 3.4)

Fire Pump Components

Tank and Piping Symbols (Clause 3.5)

Refer to previous section for tank filling, draining, and outlet symbols.

Design Considerations:

Symbols ensure standardized depiction of fire pump operations and connectivity.

IS 15682 - Tank and Piping Symbols (Clause 3.5)

Key Symbol Designations

Engineering Formulas:

• Tank volume for cylindrical tanks: [ V = \pi r^2 h ]

• Pressure loss in pipes (Darcy-Weisbach): [ \Delta P = f \frac{L}{D} \frac{\rho v^2}{2} ]

• Filling time: [ t = \frac{V}{Q} ]

• Pressure vessel design to follow IS 2825 with safety considerations.

Notes:

• Fire pump connections and level indicators are critical for operations.

IS 15682 - Pressure Vessel Symbolization (Clause 3.6)

Symbol Assignments (Table 3.6)

Design Considerations:

• Design pressure, temperature, and material per IS standards.
• Shell thickness calculation for cylindrical vessels: [ t = \frac{P \times D}{2 \times \sigma \times \eta + P} ]
• Corrosion allowance and joint efficiency are included.
• Safety valves and drain provisions are mandatory.

graph LR
A[Pressure Vessel] --> B[Inlet / Pressurizing Vessel]
A --> C[Outlet]
A --> D[Drain]
A --> E[Decompression Valve]
A --> F[Pressure Regulation Valve]
A --> G[Purging Valve]

Refer IS 2825 for detailed pressure vessel design.

IS 15682 - Aerial Appliance Symbols and Controls (Clause 3.7)

Categories Covered:

• Cage load capacity indicator
• Turntable ladder controls:
  • Rotate clockwise/anticlockwise
  • Extend/retract ladder
  • Elevate/depress ladder
  • Ladder alignment
• Hydraulic platform controls:
  • Rotate clockwise/anticlockwise
  • Extend/retract boom
  • Elevate/depress boom
• Cage rotation controls:
  • Rotate clockwise/anticlockwise

Symbol Usage:

• Each function corresponds to a specific graphical symbol as per Clause 3.7.
• Symbols enable operators to quickly identify and operate controls safely.

Design Notes:

• Cage load capacity must comply with safety standards.
• Control movements should be smooth and reliable.
• Symbols must be ergonomically displayed and conform to IS 15682.

Summary Table

graph TD
    A[Control Panel] --> B(Rotate Ladder CW/ACW)
    A --> C(Extend Ladder)
    A --> D(Elevate/Depress Ladder)
    A --> E(Align Ladder)
    B --> F[Turntable Mechanism]
    C --> G[Extension Mechanism]
    D --> H[Elevation Mechanism]
    E --> I[Alignment Mechanism]

Refer to Clause 3.7 for complete graphical representations.

IS 15682 - Miscellaneous Components and Symbols (Clause 3.8)

This section specifies designations and symbols for various auxiliary and mechanical components primarily related to non-electrical circuits.

Notes:

• Symbol definitions are primarily for schematic clarity.
• Only a few symbols like deflector positions are explicitly given.
• These aid in standardizing control diagrams and equipment labeling.

flowchart LR
    A[Non-electrical Circuit] --> B{Open / Closed}
    B --> C[Open]
    B --> D[Closed]
    E[Winch Controls]

Use in conjunction with other clauses for comprehensive schematics.

IS 15682: Guidelines on Legend and Symbol Scaling (Clauses 2.3 & 2.4)

Legend Requirements (Clause 2.3):

• All symbols must be clearly defined in an accompanying legend.
• The legend should be straightforward and unambiguous.

Symbol Scale Requirements (Clause 2.4):

• Symbols on any drawing must maintain the same relative scale.
• Symbol sizes should correspond proportionally to the drawing scale to ensure readability.

Sample Symbol Table

Practical Advice:

• For a drawing at 1:100 scale, a 10 mm symbol should be 20 mm at 1:50 scale.
• Maintain uniform symbol proportions throughout the document.

flowchart LR
    A[Drawing Scale] --> B[Determine Symbol Size]
    B --> C{Is Relative Scale Consistent?}
    C -->|Yes| D[Apply Uniform Scaling]
    C -->|No| E[Adjust Symbols]
    D --> F[Add Clear Legend]

Summary:

• Always define symbols clearly.
• Ensure consistent sizing relative to scale.
• Utilize IS 15682 tables for reference.

IS 15682: Recommendations for Symbol Use and Application

The standard supports the consistent design and operation of firefighting equipment through standardized symbols.

Key Tables Include:

Miscellaneous Controls (Clause 3.8)

Tank and Piping (Clause 3.5)

Aerial Appliances (Clause 3.7)

Frame, Engine, and Chassis (Clause 3.1)

Usage Suggestions:

• Employ standardized symbols for clear communication in design and operation.
• Ensure symbols are used consistently across documentation and equipment interfaces.