Code of Practice for Fire Safety of Industrial Buildings: Flour Mills

IS 13045: Scope & Key Specifications for Fire Safety in Flour Mills

• Scope:
  This code specifies minimum fire safety requirements for flour mills, including storage godowns, focusing on fire prevention, building layout, and firefighting arrangements.

• Illumination Requirements (Clause 11.1):

• Dust Bin/Hopper Safety (Clause 14.2):
  No openings allowed between adjacent bins/hoppers containing dust or dust-producing materials to prevent fire spread.

• Referenced IS Codes (Annex A):
  Includes IS 1642, 1644, 1646 (fire safety of buildings), IS 941 (blower & exhauster), IS 9537 (fire extinguisher), IS 3844 (internal hydrants), IS 13039 (external hydrants), etc.

Summary Diagram: Fire Safety Elements in Flour Mills

graph LR
A[Building Layout & Construction] --> B[Fire Prevention]
B --> C[Fire Fighting Equipment]
C --> D[Illumination Standards]
D --> E[Storage Safety - Dust Bins]
E --> F[Compliance with IS Codes]

Note: Always cross-check with statutory requirements (Factory Act, Petroleum Rules, etc.) alongside IS 13045.

IS 13045: Location and Site Planning - Key Specifications

• Minimum clear distance between factory buildings:
  90 m (Clause 3.2)

• Factory to railway sidings, yards, high tension lines:
  ≥ 300 m (Clause 3.3)

• Minimum distance between buildings or between building and open storage:
  6 m (Clause 6.1)

• Compound area:
  Should be sufficient to accommodate the mill block, godowns, and open storage (Clause 4.1).

Summary Table

Notes:

• These distances ensure fire safety, operational efficiency, and safe clearance from hazards.
• Site planning must consider adequate space for future expansion and safe material handling.

graph LR
A[Factory Building 1] ---|90 m| B[Factory Building 2]
A ---|≥300 m| C[Railway Sidings / HT Lines]
A ---|6 m| D[Open Storage]
B ---|6 m| D

This diagram illustrates minimum clearances for safe site layout.

IS 13045: Factory Compound & Accessibility Key Points

Compound Area & Spacing (Clauses 3.2, 4.1, 6.1)

• Compound area must be adequate for mills, godowns, and open storage.
• Minimum clear distance between factories:
  90 m (if near each other)
• Minimum distance between buildings or storage units within a factory:
  6 m

Illumination Requirements (Clause 11.1, Table 11)

Summary Diagram

graph TD
    A[Factory Compound] --> B[Mill Block]
    A --> C[Godowns]
    A --> D[Open Storage]

    B ---|90 m| E[Adjacent Factory]
    B ---|6 m| C
    C ---|6 m| D

    subgraph Illumination
        I1[Roller purifier, silks, packing floors: 150 Lux]
        I2[Wetting tables: 300 Lux]
        I3[Godowns, loading bays, packing, dispatch: 150 Lux]
        I4[Open compounds: 50 Lux]
    end

Use these spacing and illumination specs to ensure safety, accessibility, and fire-fighting effectiveness in factory layouts per IS 13045.

IS 13045: Building Construction and Separation - Key Points

1. Building Separation Distances (Clause 6.1)

• Maintain minimum 6 m distance between:
  • Two buildings
  • Building and open storage
  • Different types of open storage in a factory

2. Separation Walls (Clause 5.7)

• Buildings for storage of grains, flour, bread stuff, hazardous goods must be separated from mills or wheat cleaning areas by a separating wall to prevent contamination and fire spread.

3. Openings Between Adjacent Bins/Hoppers (Clause 14.2)

• No openings allowed between adjacent bins/hoppers containing dust or dust-producing materials to avoid dust migration and explosion hazards.

4. Doors and Windows (Clause 8.3)

• Specific provisions for doors and windows to ensure fire safety and containment (details in Clause 8.3).

Summary Table: Separation Requirements

flowchart LR
    A[Building 1] ---|6 m min| B[Building 2]
    A ---|6 m min| C[Open Storage]
    D[Grain Storage] ---|Separation Wall| E[Mill/Wheat Cleaning]
    F[Bin 1] -. No Openings .-> G[Bin 2]

This ensures safe separation to reduce fire, contamination, and explosion risks per IS 13045.

IS 13045: Key Specifications for Open Spaces and Waste Management

Open Spaces

• Minimum distance between buildings/storage:
  Maintain 6 m clearance between any two buildings, or between buildings and open storage, or between different types of open storage (Clause 6.1).

• Compound area:
  The factory compound must be large enough to accommodate the mill block, godowns, and open storages (Clause 4.1).

Waste Management

• Oily/greasy waste:
  No oily or greasy waste should be dumped openly in the compound to prevent fire hazards (Clause 6.2).

Illumination for Safety (Clause 11.1)

flowchart LR
    A[Factory Compound] --> B[Mill Block]
    A --> C[Godowns]
    A --> D[Open Storage]
    B ---|6 m gap| C
    C ---|6 m gap| D
    B ---|6 m gap| D

Summary: Maintain 6 m spacing for fire safety, avoid open oily waste dumping, and ensure adequate illumination per area for fire-fighting readiness.

IS 13045 – Exit Requirements Summary

• Exit Doorway Dimensions (Clause 7.4):

  • Minimum width: 100 cm (1.0 m)
  • Minimum height: 200 cm (2.0 m)

• Exit Staircase Landing (Clause 7.3):

  • Minimum size: 1.5 m × 1.5 m
  • Hydrant posts for wet riser system to be installed at landings (per IS 3844:1989)

• General Exit Compliance (Clause 7.1):

  • All exits and fire escapes must comply with IS 1644:1988 for fire safety design.

Key Points:

Additional Notes:

• Exits must follow IS 1644:1988 for detailed fire escape design, including number, location, and capacity.
• Proper maintenance and clear access to exits are critical for safety.

flowchart TD
    A[Building Floor] --> B[Exit Doorway]
    B --> C[Exit Staircase]
    C --> D[Landing (1.5m x 1.5m)]
    D --> E[Hydrant Post (Wet Riser)]
    E --> F[Exit to Safety]

This ensures safe and compliant egress routes in buildings per IS 13045.

IS 13045: Storage and Ventilation Key Points

Ventilation (Clause 8.5.1)

• Ventilator openings in corrugated iron sheet roofs:
  • Max size: 1.2 m × 0.3 m
  • At least one ventilator opening every alternate day
  • Protection: Expanded metal or wire netting with 12.5 mm apertures
• Fire safety: Individual ventilation ducts must have fire smoke dampers to stop air supply during fire.
• For mechanical ventilation, refer to IS 941:1985 (Blower and exhauster for fire fighting).

Storage (Clause 14.2)

• No openings between adjacent bins or hoppers containing dust or dust-producing materials to prevent cross contamination or dust spread.

Door and Window Specifications (Clause 8.3.1)

• Doors:
  • Max area: 6.25 m²
  • Close-fitting and protected against damage.
• Ventilators:
  • Located at least 3 m above ground
  • Protected by 6 mm wired glass in steel frames
• Fireman's windows:
  • 6 mm wired glass, steel frame, locked normally
  • Max spacing: 15 m apart, and 7 m from blind corners

Summary Table: Ventilator Opening Size

flowchart LR
    Roof --> Ventilator[Ventilator Opening]
    Ventilator --> Protection[12.5 mm mesh]
    Ventilator --> FireDamper[Fire Smoke Damper]
    Ventilator --> MechanicalVent[Mechanical Ventilation (IS 941)]

This ensures adequate ventilation with fire safety in storage buildings per IS 13045.

IS 13045: Machinery Installation and Operation - Key Points

Bearings (Clause 9.1)

• Use ball or roller bearings for all machinery and line shafts to ensure smooth operation and reduce frictional heat.

Dust Control (Clause 9.2 & 9.6)

• Machinery must be installed to prevent dust access/accumulation on moving parts.
• No dust/exhaust rooms inside the mill.
• Dust collection limited to rollers, purifiers, centrifugals.
• Use only automatic cyclone or whirl dust collectors made of strong metal.

Fire Safety (General Overview)

• Fires often caused by frictional heat from rollers and sparks from foreign materials.
• Key preventive measures:
  • Proper building layout and external staircases.
  • Avoid combustible building materials.
  • Maintain good housekeeping and reduce congestion.
  • Use adequate firefighting equipment.
  • Follow statutory rules like Indian Factory Act, Petroleum Rules, Gas Cylinder Rules.

Summary Table

flowchart TD
    A[Machinery Installation] --> B[Use ball/roller bearings]
    A --> C[Prevent dust accumulation]
    C --> D[Automatic cyclone/whirl dust collectors]
    A --> E[No dust rooms inside mill]
    A --> F[Fire safety measures]
    F --> G[Good housekeeping]
    F --> H[Non-combustible materials]
    F --> I[External staircases]
    F --> J[Firefighting equipment]

This concise guidance ensures machinery longevity, operational safety, and fire prevention in flour mills per IS 13045.

IS 13045: Electrical Installation Key Points

• General Installation:
  Follow IS 1646:1982 for electrical installation practices in textile mills.

• Wiring:
  Use steel conduits as per IS 1653:1972 or rigid non-metallic conduits as per IS 9537 (Part 3):1973 for all wiring.

• Switchgear:
  Must be dust-tight type when installed in mill houses (Clause 10.5) to prevent dust ingress, ensuring safety and reliability.

• Dust Control:
  No dust or exhaust rooms inside mills; only automatic cyclone or whirl dust collectors made of metal are allowed for dust collection (Clause 9.6).

Relevant IS Standards Summary

Typical Wiring Conduit Selection (per IS 1653 & IS 9537)

flowchart LR
    A[Electrical Installation] --> B[Wiring]
    B --> C[Steel Conduit (IS 1653)]
    B --> D[Non-metallic Conduit (IS 9537)]
    A --> E[Switchgear]
    E --> F[Dust-tight Type (Clause 10.5)]
    A --> G[Dust Control]
    G --> H[No dust rooms inside mills]
    G --> I[Automatic cyclone/whirl dust collectors]

For detailed design, consult the respective IS codes for conduit sizes, wiring methods, and switchgear specifications.

IS 13045 - Illumination Requirements for Industrial Buildings

Key Specifications (Clause 11.1, Table 11)

Additional Relevant Clauses:

• 10.3: All lighting fittings must be dust-tight.
• 10.4: Only electric light is permitted; no artificial light other than electric.
• 10.5: Switchgear must be dust-tight type.

Notes:

• Illumination (Lux): Measure of luminous flux per unit area; ensures visibility for fire fighting and operational safety.
• Limiting Glare Index: Controls glare to avoid visual discomfort, max 25 for critical areas.

Summary Diagram (Lighting Setup)

graph LR
A[Industrial Area] --> B[Lighting Fittings (Dust-tight)]
B --> C[Minimum Lux as per Area]
C --> D[Glare Control (Index ≤ 25)]
D --> E[Safe & Effective Illumination]

Use these values to design lighting systems ensuring safety and operational efficiency in mills per IS 13045.

IS 13045: Fire Fighting Arrangements for Flour Mills

Key Specifications:

• First-aid Fire Fighting Equipment:

  • As per IS 2190:1979.
  • Equipment must be placed near fire-prone areas (motors, switchboards, starters) or near exits/staircase landings.
  • Distribution such that no person travels more than 15 m to reach the nearest equipment.
  • Placement must not obstruct passage.

• Internal Hydrant System:

  • Conform to IS 3844:1989.

• External Hydrant System:

  • Conform to IS 13039:1991.

• Emergency Lighting:

  • As per Clause 11.2, emergency lighting must operate on failure of normal power supply.

Important Notes:

• Fire causes include frictional heat, sparks from foreign material, bad housekeeping, faulty electricals, building height, and combustible materials.
• Fire safety also involves building layout, external staircases, and storage arrangements.

Quick Reference Table for Fire Equipment Placement

flowchart LR
    A[Fire Prone Areas] --> B[First Aid Fire Equipment]
    C[Exits & Staircase Landings] --> B
    B -->|Max 15 m travel| D[Personnel Access]
    E[Power Failure] --> F[Emergency Lighting]

For detailed design, refer to IS 2190, IS 3844, and IS 13039 as indicated.

IS 13045: Housekeeping Key Points & Specifications

1. Horizontal Surfaces (Clause 5.8)

• Minimize horizontal surfaces to reduce dust accumulation.
• Inaccessible horizontal surfaces must be inclined steeply for cleaning.
• All surfaces (horizontal/flat) must be smooth to facilitate cleaning.

2. Fire Warning System (Clause 12.3)

• Warning system must be audible throughout factory and compound.
• Warning appliance location: conspicuous and painted red (IS 5:1978, Colour No. 536).

3. Cleaning Frequency & Method (Clause 13.1)

• Sweepings removed before nightfall.
• Rope alloys cleaned daily.
• Machinery, walls, floors, platforms cleaned at least weekly.
• Use vacuum or air blowers only after shutting down electrical equipment to avoid dust clouds.

4. Illumination Requirements for Fire Fighting (Clause 11.1)

Summary Diagram: Cleaning & Fire Safety Flow

flowchart TD
    A[Minimize Horizontal Surfaces] --> B[Incline Inaccessible Surfaces]
    B --> C[Smooth Surface Finish]
    C --> D[Weekly Cleaning of Machinery & Floors]
    D --> E[Daily Cleaning of Rope Alloys]
    E --> F[Remove Sweepings Before Nightfall]
    F --> G[Use Vacuum/Air Blowers After Shutdown]
    G --> H[Fire Warning System Installed]
    H --> I[Audible & Conspicuous Location]
    I --> J[Painted Red (IS 5:1978, No. 536)]
    J --> K[Maintain Illumination Levels for Fire Fighting]

This ensures dust control, safety, and compliance with IS 13045 housekeeping standards.

IS 13045 - Key Specifications for Flour Bins and Hoppers

• Material: Flour bins and hoppers inside mills must be non-combustible or fire-resistive (Clause 14.1).
• Openings: No openings are allowed between adjacent bins or hoppers containing dust or dust-producing materials to prevent dust spread and fire risk (Clause 14.2).
• Housekeeping: Avoid depositing oily or greasy waste openly in the compound to reduce fire hazards (Clause 13.6).

Summary Table (Clause 14.2)

Additional Fire Safety Measures (Referenced IS Codes)

• IS 1642:1989 - Fire safety materials and construction details
• IS 1644:1988 - Personal hazard materials
• IS 1646:1982 - Electrical installation safety in buildings

graph TD
    A[Flour Bins & Hoppers] --> B[Non-combustible Material]
    A --> C[No Openings Between Adjacent Bins]
    A --> D[No Oily Waste Deposited Nearby]
    B --> E[Fire Resistance Ensured]
    C --> F[Prevents Dust Spread]
    D --> G[Reduces Fire Hazard]

Note: For detailed design and fire safety installation, consult IS 1642, IS 1644, and IS 1646 as referenced in IS 13045 Annex A.