Recommendations for preventive measures against hazards at workplaces, Part 4: Timber structures
1994 Edition

Summary of Scope in IS 13416 Part 4 (1994)

Scope Highlights:

• Addresses occupational safety specifically related to timber handling, fabrication, and construction of timber frameworks.
• Excludes safety considerations in masonry and concrete operations.
• Emphasizes protective gear, handling techniques, and preventive actions during timber construction.

Important Safety Provisions:

• Protective Equipment: Provision of helmets, protective clothing, safety footwear in proportion to workforce (Clause 7.2).
• Truss Handling: Tilt cautiously to prevent excessive bending and reversal stresses in upper chords.
• Framing: Temporary bracing to shield compression components until full assembly.
• Sling Attachment: Position to avoid embedding damage in laminated wood.
• Scaffolds and Ladders: Adhere to IS 3696 (Parts 1 & 2) safety guidelines.
• Training: Ensure carpenters receive instruction on hazard awareness and safety methods.

Referenced Indian Standards (Annex A):

Practical Advice for Pitched Roof Tasks (Clause 5.3):

• Employ a bamboo or eucalyptus pole (70-100 mm diameter) securely fastened parallel to the eaves as a work base.

flowchart TD
    A[Workplace Safety] --> B[Protective Gear]
    A --> C[Timber Handling Practices]
    C --> D[Truss Handling]
    C --> E[Temporary Bracing]
    C --> F[Sling Positioning]
    A --> G[Training & Awareness]
    A --> H[Scaffold and Ladder Safety]

Synopsis: This part concentrates on safety in timber construction by emphasizing appropriate PPE, handling techniques, bracing, and training, supported by related IS standards.

Key Points on Timber Handling Safety (Clause 3)

• Handling timber involves risks during cutting, assembling, erecting, and transport.
• Avoid sudden impacts on slender timber to prevent fractures at weak spots like knots.
• Bundle smaller timber pieces for safer transport.
• Heavy or large timber should be moved using mechanical aids such as carts, trolleys, or trucks.
• Utilize strong ropes, wires, poles, or rods to assist in controlling timber movements.
• When loading or unloading on inclined surfaces:
  • Take care to prevent timber from falling.
  • Provide clear warning signals to personnel working below.

Safety Measures Table:

Additional Information:

• Fire safety aspects are covered in IS 13416 Part 5.
• These guidelines recommend approved practices but allow alternatives upon authorization.

flowchart LR
    A[Timber Processing] --> B[Safe Handling]
    B --> C{Timber Size}
    C -->|Slender| D[Avoid Sudden Force]
    C -->|Small| E[Bundle for Carrying]
    C -->|Large| F[Use Mechanical Aids]
    F --> G[Employ Ropes & Poles]
    G --> H[Safe Loading/Unloading]
    H --> I[Issue Warning Signals]

Note: The clause focuses on procedural safety; no explicit formulas are provided.

Tool Safety Guidelines (Clause 4.2 and 3.2.1)

• Tools such as drills, chisels, hammers, nails, and bolts must not be placed carelessly on elevated platforms.
• Maintain a minimum distance of 500 mm from platform edges for all tools and tool containers to prevent falling hazards.
• Fragile materials should never serve as supports or ladders for workers at height.
• Use secure tool belts, lanyards, or designated storage to prevent accidental dropping.
• Regular inspections of tools and storage setups are necessary.

Tool Safety Distance Summary:

flowchart LR
    A[Tools on Elevated Platforms] --> B{Distance from Edge}
    B -- < 500 mm --> C[Unsafe: Risk of Falling]
    B --  500 mm --> D[Safe Zone]
    A --> E[Use of Tool Belts and Lanyards]
    E --> D

Note: Refer also to IS 13416 Part 5 for related fire safety requirements.

Guidelines for Elevated Timber Work (Clauses 4.2, 5.3, 6)

• Tool Placement: Keep all tools, toolboxes, nails, and bolts at least 500 mm away from the edges of working platforms to avoid falls.
• Roof Work Support: Use a strong bamboo or eucalyptus pole (70–100 mm diameter) fixed parallel to the eaves and tied securely from the ridge to provide a safe working base without obstructing roofing.
• General Safety: Follow approved safety protocols for handling, fixing, and supporting timber elements such as beams, columns, and trusses.
• Additional Reference: Fire safety during elevated timber work is covered in IS 13416 Part 5.

Safety Summary Table:

flowchart LR
    A[Platform Edge] -->|>= 500 mm| B[Safe Tool Zone]
    C[Pitched Roof] --> D[Support Pole Setup]
    D --> E[Worker Support]
    E --> F[Roof Covering Placement]

Adhering strictly to these measures helps prevent accidents and injuries during work at height.

Safety Requirements for Timber Component Fabrication and Assembly (Clause 1.1, 5.3)

• Covers all phases including timber processing, jointing of beams, columns, trusses, and purlins, and structure erection with roof covering.
• For pitched roofs, a strong bamboo or eucalyptus pole (70–100 mm diameter) should be tied along the eaves as a working platform.
• Enforce institutional safety measures, including:
  • Adequate supervision and training.
  • Use of suitable personal protective gear.
  • Adoption of approved fabrication and handling methods.
• Fire hazard precautions are referenced in IS 13416 Part 5.

Support Pole Specifications:

flowchart LR
    A[Timber Processing] --> B[Component Jointing]
    B --> C[Erection Procedures]
    C --> D[Roof Covering Installation]
    D --> E[Use of Pole Support]
    E --> F[Ensured Worker Safety & Roof Placement]

Note: Any variations require prior approval from the relevant authorities.

Warning Signal Protocols (Clause 7.1)

• Mandates installation of clear warning signs and notices near work zones to highlight hazards.
• Includes:
  • Visual Indicators: Written notices specifying risks and safety instructions.
  • Audible Alerts: Verbal warnings by supervisors or experienced workers to ensure attention.
• Signals must be visible, frequent, and comprehensible to effectively prevent accidents.
• No specific calculation or tabular data included in the standard for signals.

Recommended Practices:

flowchart LR
    A[Hazardous Area] --> B[Visual Warning Signs]
    A --> C[Verbal/Audible Alerts]
    B & C --> D[Worker Awareness]
    D --> E[Accident Prevention]

Summary: The standard requires prominent, understandable warning signals combining sight and sound to safeguard workers.

IS 13416 Part 4 cites various Indian Standards vital for ensuring safety in timber handling and construction. While the full list in Annex A is not shown here, commonly referenced codes include:

• IS 456: Plain and Reinforced Concrete Practice
• IS 800: Steel Construction Code
• IS 875: Design Loads (Dead, Live, Wind, Seismic)
• IS 1905: Structural Use of Unseasoned Timber
• IS 2878: Structural Timber Code

Key Points:

• The scope excludes masonry and concrete safety.
• Focuses primarily on timber-related safety.

Advice:

Consult Annex A of IS 13416 Part 4 for the full list of applicable Indian Standards required for compliance.

flowchart LR
    A[IS 13416 Part 4] --> B[Timber Handling Safety]
    A --> C[Annex A: Referenced IS Codes]
    C --> D[IS 456 - Concrete]
    C --> E[IS 800 - Steel]
    C --> F[IS 875 - Load Codes]
    C --> G[IS 1905 - Unseasoned Timber]
    C --> H[IS 2878 - Structural Timber]

For detailed formulations and data, consult the individual standards.

Details of the Committee Responsible for IS 13416 Part 4 (Annex B)

The Safety in Construction Sectional Committee, CED 45, comprises specialists from various government bodies, industry, research, and safety organizations:

• Alternate members are nominated for most representatives.
• This diverse committee ensures multi-disciplinary expertise for the standard's development.

graph TD
    A[Committee Composition] --> B[Chairman: Maj Gen S.N. Bouri]
    A --> C[Members from Govt, Industry, Research]
    C --> D[Ministries, CPWD, Railways, Power, Steel]
    C --> E[Research Institutes & Safety Councils]
    C --> F[Alternate Members]

This structure guarantees comprehensive input and oversight in the formulation of safety standards.