Code of practice for safety during additional construction and alteration to existing buildings

IS 13430: Scope Summary & Key Specifications

Scope:
IS 13430 prescribes safety requirements during additional construction and alteration of existing buildings to minimize accidents and injuries to workers and the public.

Key Points:

• Applicability: Safety during various construction operations and alterations.
• Safety Measures: Includes scaffolds, ladders, excavation, electrical work, hoisting machines.
• Related IS Codes:
  • IS 3696 (Part 1 & 2): Safety code for scaffolds and ladders.
  • IS 3764: Excavation work safety.
  • IS 4081: Safety for blasting and drilling.

Important Specifications:

Reference for Scaffold Safety (IS 3696):

Guard Rail Height ≥ 90 cm  
Scaffold Stability: Fixed to prevent swaying  
Use safety harness if height > 3.5 m

flowchart TD
    A[Additional Construction & Alteration] --> B[Safety Measures]
    B --> C[Scaffolds & Ladders]
    B --> D[Excavation Safety]
    B --> E[Electrical Safety]
    B --> F[Hoisting Machines]
    C --> G[Guard Rail ≥ 90 cm]
    C --> H[Secure Fixing]

Note: Always refer to the latest version of IS 13430 and related standards for detailed safety protocols.

IS 13430: General Safety Requirements - Key Points

This code addresses safety during additional construction and alteration of existing buildings, emphasizing accident risk minimization.

Key Safety Specifications:

• Safe Access (Clause 5.3):

  • Provide safe means of access to all working platforms.
  • Use ladders conforming to IS 3696 (Part 2):1991 (Safety code for ladders).
  • Ladders must be securely fixed.

• Electrical Safety (Clause 9.7.5):

  • Workers on energized electrical installations must use insulating mats, gloves, sleeves, and insulated tools.
  • Remove conductive items like rings, watches, keys.

Related IS Codes for Safety:

Summary Table: Ladder Safety (per IS 3696 Part 2)

flowchart TD
    A[Safe Access Required] --> B[Use IS 3696 Compliant Ladders]
    B --> C[Secure Fixing of Ladders]
    A --> D[Safe Working Platforms]
    E[Electrical Work] --> F[Use Insulating Mats & Gloves]
    F --> G[Remove Conductive Items]

Note: Always refer to the latest edition and amendments of IS 13430 and related codes for detailed safety procedures.

IS 13430: Excavation and Trenching - Key Specifications & Safety Measures

Key Clauses & Specifications:

• Trench Depth & Ladders (Clause 3.5):

  • Trenches ≥ 1.2 m deep must have at least one ladder per 30 m length.
  • Ladder extends from trench bottom to 90 cm above ground.

• Trench Side Stability:

  • Trenches ≥ 1.5 m deep must have:
    • Stepped back sides with a suitable slope, or
    • Timber bracing/shoring to prevent collapse.

• Excavated Material Placement:

  • Place excavated soil at least 1.5 m away from trench edge or half the trench depth, whichever is greater.

• Excavation Method:

  • Cut from top to bottom only.
  • No undermining or undercutting allowed.

• Safety Fencing & Lighting (Clause 3.1):

  • Trenches/foundation pits must be fenced and marked with caution signs and red lights at night.

• Shoring and Strutting (Clause 3.6):

  • Must closely follow excavation progress to ensure safety.

Additional Safety Notes:

• Avoid damage to adjoining structures.
• Protective measures must be taken to prevent accidents.
• Follow related IS codes for scaffolds (IS 3696) and excavation safety (IS 3764).

Typical Slope Recommendations for Trench Sides (Based on Soil Type):

flowchart TD
    A[Start Excavation] --> B{Depth ≥ 1.2 m?}
    B -- Yes --> C[Provide ladder every 30 m]
    C --> D{Depth ≥ 1.5 m?}
    D -- Yes --> E[Step back sides or provide shoring]
    D -- No --> F[Proceed with excavation

Key Specifications and Formulas for Scaffold and Ladders (IS 13430 referencing IS 3696 & IS 3764):

Scaffold (Clause 4.2)

• Guard Rail Height: Minimum 90 cm above platform/floor for scaffolds ≥ 3.5 m high.
• Guard Rail: Must be securely bolted, braced, and fixed to prevent swaying.
• Openings: Allowed for material delivery.
• Attachment: Scaffold must be fixed to the building or structure to prevent swaying.

Ladder (Clause 4.1)

• Inclination: Ladder slope not steeper than 1:4 (1 horizontal : 4 vertical).
• Support: An extra worker (mazdoor) to hold ladder when in use.
• Features: Provide footholds and handholes if materials are carried.
• Use: For short duration work only; otherwise use scaffolds.

Safety Codes to Follow:

• IS 3696 (Part 1 & 2): Detailed safety codes for scaffolds and ladders.
• IS 3764: Excavation safety, applicable as per site conditions.

Ladder Inclination Diagram (1:4 slope)

graph LR
A[Ground] -- 1 unit horizontal --> B[Base of Ladder]
B -- 4 units vertical --> C[Top of Ladder on platform]

Summary Table

Always refer to IS 3696 for detailed construction, materials, and load requirements.

IS 13430 Key Points on Working Platforms, Gangways, and Stairways

1. Guard Rails (Clause 4.2)

• Required for scaffolding ≥ 3.5 m height.
• Height of guard rail: ≥ 90 cm above platform/floor.
• Must be properly bolted, braced, and secured.
• Openings allowed for material delivery.
• Scaffolding must be fixed to prevent swaying.

2. Construction Requirements (Clause 5.1)

• Platforms, gangways, stairways must not sag unduly or unequally.
• For height > 3.5 m, use closely secured planks fastened properly.

3. Safe Access (Clause 5.3)

• Safe means of access to all platforms.
• Ladders must be securely fixed.
• Use ladders conforming to IS 3696 (Part 2):1991.

4. Reference Standards

• Follow IS 3696 Parts 1 & 2 for scaffold and ladder safety.
• Follow IS 3764:1992 recommendations for scaffolding depending on site.

Typical Dimensions (per IS 3764 and IS 3696)

Diagram: Guard Rail and Platform Setup

graph TD
    A[Ground/Floor Level]
    B[Working Platform ≥ 3.5m]
    C[Guard Rail ≥ 90 cm above platform]
    D[Planks closely secured]
    E[Scaffolding fixed to structure]

    A --> B --> C
    B --> D
    B --> E

Summary: Ensure platforms and gangways above 3.5 m have secured planks and guard rails ≥ 90 cm high, stable scaffolding fixed to the structure, and safe access via fixed ladders per IS 3696.

IS 13430 - Electrical Installations and System: Key Points

Safe Electrical Work Practices (Clause 9.7.5)

• When working on energized electrical installations:
  • Use insulating mats, gloves, sleeves, and tools.
  • Workers must not wear rings, watches, keys, or any conductive material.

Installation Safety (Clause 6.1 & 6.2)

• Precautions must be taken to prevent electrical hazards (detailed guidelines under preparation).
• Temporary electrical lines must be:
  • Hung overhead (not on floors).
  • Protected against damage.

Ladder Requirements (Clause 5.3)

• Ladders must conform to IS 3696 (Part 2):1991.
• Securely fixed for safe access.

Summary Table: Electrical Safety Essentials

flowchart TD
    A[Electrical Installation] --> B[Safe Access]
    B --> C[Ladders per IS 3696]
    A --> D[Working on Energized Systems]
    D --> E[Use Insulating Mats & PPE]
    D --> F[No Conductive Items Allowed]
    A --> G[Temporary Wiring]
    G --> H[Overhead Hanging]
    G --> I[Protection from Damage]

For detailed electrical safety design, refer to IS standards on electrical installations and preventive measures once published.

IS 13430 - Stacking of Materials (Clause 7)

• Safety First: Materials must not be stacked in a way that causes danger or inconvenience to workers or the public.
• Protection Measures: Provide fencing and lighting around stacked materials to prevent accidents.
• Height & Stability: Although the code doesn’t specify exact stacking heights or load limits, general practice recommends:
  • Stack materials on level, firm ground.
  • Keep stacks stable and avoid overhanging.
  • Limit stack height based on material type and stability (e.g., bricks max 1.2 m).
• Access & Clearance: Maintain clear access paths and ensure stacks do not obstruct gangways or emergency exits.

Related IS Codes for Reference:

• IS 3696 (Parts 1 & 2): Safety in scaffolding.
• IS 3764:1992: Guidelines for working platforms and gangways.

Summary Table (Typical Stacking Limits)

flowchart TD
    A[Materials Delivered] --> B[Check Ground Levelness]
    B --> C{Is Ground Level & Firm?}
    C -- Yes --> D[Stack Materials Safely]
    C -- No --> E[Prepare Ground]
    D --> F[Provide Fencing & Lighting]
    F --> G[Maintain Clear Gangways]
    G --> H[Regular Inspection]

Note: Always follow site-specific safety plans and consult IS codes for detailed requirements.

IS 13430 - Protective Barriers: Key Points

• Clause 8: Protective barriers must be erected where there is risk of structural collapse to barricade and support the area.
• Clause 7.4: Remove or bend over any projecting nails to prevent injury.
• Protective barriers should be:
  • Strong enough to prevent unauthorized access.
  • Clearly visible and well-marked.
  • Adequately supported to withstand impact or collapse loads.

Typical Specifications (from general engineering practice):

Safety Measures:

• Barricade hazardous zones immediately.
• Use warning signs and lighting if required.
• Regular inspection and maintenance of barriers.

flowchart LR
    A[Danger of Collapse] --> B[Set up Protective Barrier]
    B --> C[Remove/Bend Projecting Nails]
    B --> D[Support Barrier Adequately]
    D --> E[Prevent Unauthorized Access]
    E --> F[Regular Inspection]

For detailed design loads and materials, refer to IS 3696 (Scaffolds) and IS 3764 (Excavation Safety).

Safety Equipment for Workers (IS 13430 - Clause 9)

Key Specifications:

• Electrical Work (Clause 9.7.5):

  • Use insulating mats and wearing apparel: gloves, sleeves, and insulated tools.
  • Workers must not wear rings, watches, keys, or any conductive materials.

• Welding (Clause 9.4):

  • Provide welders protective eye shields to workers engaged in welding.

• General Safety:

  • Remove or bend over projecting nails (Clause 7.4).
  • Barricade areas where there is a danger of structural collapse (Clause 8).

Summary Table: Electrical Safety Equipment

flowchart TD
    A[Worker on Energised Electrical Installation]
    A --> B[Wear Insulating Gloves & Sleeves]
    A --> C[Stand on Insulating Mats]
    A --> D[Use Insulated Tools]
    A --> E[Remove Metal Accessories]

Note: Always refer to related IS codes for scaffolds (IS 3696), excavation (IS 3764), and blasting (IS 4081) for comprehensive safety requirements.

IS 13430 - Use of Hoisting Machines (Clause 9.7) Summary

Key Specifications:

• Mechanical Integrity: Hoisting machines, tackles, attachments, anchorage, and supports must be of sound material, good mechanical construction, adequate strength, and free from defects (9.7.1a).
• Ropes: Must be durable, adequate strength, and defect-free (9.7.1b).
• Safe Working Load (SWL):
  • Must be ascertained by approved means for all hoisting machines and accessories (chains, hooks, shackles, etc.) (9.7.2).
  • Machines must be clearly marked with SWL.
  • Variable SWL machines must display each SWL and applicable conditions.
  • No loading beyond SWL except for testing.

Safety Measures (9.7.5):

• When working on energized electrical installations, provide insulating mats, gloves, sleeves, and tools.
• Workers should avoid wearing conductive items (rings, watches, keys).

Typical Formulas/Checks (General Engineering Practice):

• SWL Calculation:
  [ \text{SWL} = \frac{\text{Breaking Load}}{\text{Factor of Safety}} ]

  • Typical Factor of Safety (FoS) for hoisting ropes and chains: 5 to 7.

• Rope Strength:
  Check rope diameter and material per manufacturer's data or IS standards for wire ropes.

Diagram: Hoisting Machine Components

graph LR
A[Hoisting Machine] --> B[Wire Rope]
A --> C[Chain, Hook, Shackle]
A --> D[Anchor & Support]
B --> E[Load]
C --> E
D --> E

Summary: IS 13430 Clause 9.7 ensures hoisting machines and accessories are robust, defect-free, and clearly marked with safe working loads. Safety gear is mandatory for electrical works. Always adhere to SWL limits and inspect equipment regularly.