Code of practice for safety during additional construction and alteration to existing buildings
1992 Edition

Overview of Safety Code Scope

Purpose:
This standard establishes safety requirements for additional construction and alterations on existing buildings to reduce injury risks to workers and the public.

Highlights:

• Coverage: Safety in various construction and modification activities.
• Safety Topics: Scaffolding, ladders, excavation, electrical works, hoisting equipment.
• Associated Standards:
  • IS 3696 (Parts 1 & 2): Safety codes for scaffolds and ladders.
  • IS 3764: Excavation safety procedures.
  • IS 4081: Safety in blasting and drilling operations.

Key Technical Details:

Scaffold Safety Reference (IS 3696):

Guard Rail Height 290 cm  
Secure Scaffold Fixing to avoid movement  
Safety harness required if height exceeds 3.5 m

flowchart TD
    A[Additional Building Work] --> B[Safety Measures]
    B --> C[Scaffolds and Ladders]
    B --> D[Excavation Safety]
    B --> E[Electrical Precautions]
    B --> F[Hoisting Equipment]
    C --> G[Guard Rail Height 290 cm]
    C --> H[Secure Scaffold Fixing]

Reminder: Always consult the most current version of IS 13430 and relevant standards for comprehensive safety protocols.

General Safety Principles in IS 13430

This code highlights essential safety practices during supplementary construction and alteration of buildings, focusing on minimizing accident risks.

Important Safety Measures:

• Safe Access (Clause 5.3):

  • Provide secure access to all working platforms.
  • Use ladders complying with IS 3696 (Part 2):1991.
  • Ladders must be fastened securely.

• Electrical Safety (Clause 9.7.5):

  • Personnel working on live electrical installations should use insulating mats, gloves, sleeves, and insulated tools.
  • Remove any conductive jewelry or items such as rings, watches, and keys.

Related Standards:

Ladder Safety Summary (IS 3696 Part 2):

flowchart TD
    A[Safe Platform Access] --> B[Use IS 3696 Compliant Ladders]
    B --> C[Ensure Secure Fixing]
    A --> D[Safe Working Platforms]
    E[Electrical Tasks] --> F[Employ Insulating PPE]
    F --> G[Remove Conductive Items]

Note: Always verify against the latest IS editions and amendments for detailed safety guidelines.

IS 13430 Excavation and Trenching: Essential Safety Guidelines

Key Clauses:

• Ladders in Trenches (Clause 3.5):

  • Trenches deeper than 1.2 m require at least one ladder per 30 meters.
  • Ladder must extend from trench bottom to at least 90 cm above ground.

• Trench Wall Stability:

  • Trenches over 1.5 m deep must have stepped back sides with an appropriate slope or be supported by timber bracing/shoring to prevent collapse.

• Placement of Excavated Earth:

  • Soil must be placed at a minimum distance of 1.5 m, or half the trench depth, away from trench edges.

• Excavation Procedure:

  • Excavation must proceed from the top downwards only.
  • Undermining or undercutting is prohibited.

• Safety Fencing and Lighting (Clause 3.1):

  • Trenches and foundation pits should be fenced off and marked with warning signs and red lights during nighttime.

• Shoring and Strutting (Clause 3.6):

  • Support systems must progress in tandem with excavation to ensure safety.

Additional Safety Advice:

• Prevent damage to nearby structures.
• Implement protective measures to avoid accidents.
• Refer to IS 3696 for scaffolding and IS 3764 for excavation safety.

Recommended Trench Side Slopes by Soil Type:

flowchart TD
    A[Begin Excavation] --> B{Is Depth 21.2 m?}
    B -- Yes --> C[Provide Ladder every 30 m]
    C --> D{Is Depth 21.5 m?}
    D -- Yes --> E[Step back or brace sides]
    D -- No --> F[Continue Excavation]
    B -- No --> F

This framework ensures safety and structural integrity during excavation and trenching.

Key Specifications for Scaffold and Ladder Safety Referencing IS 13430, IS 3696 & IS 3764

Scaffold Requirements (Clause 4.2)

• Guard rails must be at least 90 cm high on scaffolds taller than 3.5 m.
• Guard rails should be firmly bolted and braced to prevent movement.
• Openings in guard rails are allowed for material handling.
• Scaffolds must be anchored securely to the structure to avoid swaying.

Ladder Requirements (Clause 4.1)

• Ladder inclination should not be steeper than 1:4 (horizontal:vertical).
• A worker must hold the ladder while in use.
• Provide footholds and handholds when carrying materials.
• Ladders are intended for short-term tasks; scaffolds should be used for longer durations.

Applicable Safety Codes

• IS 3696 (Parts 1 & 2) cover detailed scaffold and ladder safety.
• IS 3764 provides excavation safety guidelines relevant to scaffolding.

Ladder Inclination Illustration (1:4 Slope)

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

Summary Table

Consult IS 3696 for comprehensive scaffold and ladder construction and material requirements.

IS 13430 Safety Guidelines for Platforms, Gangways, and Stairways

Guard Rail Specifications (Clause 4.2)

• Mandatory on scaffolds exceeding 3.5 m in height.
• Guard rails must be at least 90 cm above the platform or floor.
• Rails should be securely bolted, braced, and fastened.
• Openings are permitted to facilitate material delivery.
• Scaffolds should be firmly attached to structures to prevent movement.

Construction Requirements (Clause 5.1)

• Platforms, gangways, and stairways should not exhibit excessive or uneven sagging.
• For heights over 3.5 m, use planks that are tightly secured and well fastened.

Safe Access (Clause 5.3)

• Provide secure access to all platforms.
• Ladders must comply with IS 3696 (Part 2):1991 and be properly fixed.

Relevant Standards

• Follow IS 3696 Parts 1 and 2 on scaffold and ladder safety.
• IS 3764:1992 offers additional recommendations for scaffold use based on conditions.

Standard Dimensions (per IS 3764 and IS 3696):

Guard Rail and Platform Setup Diagram

graph TD
    A[Ground Level]
    B[Working Platform > 3.5 m]
    C[Guard Rail 290 cm above platform]
    D[Securely fastened planks]
    E[Scaffold firmly fixed]

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

Summary: Platforms and gangways exceeding 3.5 meters should have tightly secured planks and guard rails at least 90 cm high. Scaffolds must be stabilized and securely fastened, with safe access provided by ladders that meet IS standards.

Electrical Safety Guidelines under IS 13430

Safe Practices when Working on Energized Systems (Clause 9.7.5)

• Use insulating mats, gloves, sleeves, and insulated tools.
• Remove all conductive accessories such as rings, watches, and keys from workers.

Installation Precautions (Clauses 6.1 & 6.2)

• Take necessary measures to prevent electrical hazards.
• Temporary electrical wiring should be suspended overhead, not laid on floors, and protected against damage.

Ladder Usage (Clause 5.3)

• Ladders must meet the specifications of IS 3696 (Part 2):1991.
• Secure attachment is mandatory to ensure safe access.

Electrical Safety Requirements Summary

flowchart TD
    A[Electrical Installation Work] --> B[Safe Access via Ladders]
    B --> C[Use IS 3696 Compliant Ladders]
    A --> D[Work on Live Systems]
    D --> E[Employ Insulating PPE]
    E --> F[Remove Conductive Accessories]
    A --> G[Temporary Wiring]
    G --> H[Overhead Suspension]
    G --> I[Protection from Damage]

Refer to detailed electrical safety standards and codes as published for comprehensive guidance.

Material Stacking Safety Requirements (Clause 7) in IS 13430

• Hazard Prevention: Materials should not be stacked in a manner that endangers workers or obstructs public pathways.
• Safety Measures: Fencing and adequate lighting must be provided around stored materials.
• Stack Stability & Height: While the code does not specify exact limits, good practice involves:
  • Stacking on level and stable ground.
  • Ensuring stability and avoiding overhanging materials.
  • Limiting stack heights depending on material type (e.g., bricks up to 1.2 m).
• Clearance: Maintain clear access routes; stacks should not block emergency exits or gangways.

Related Standards:

• IS 3696 (Parts 1 & 2) for scaffolding safety.
• IS 3764:1992 for working platform and gangway guidelines.

Typical Stack Height Recommendations:

flowchart TD
    A[Materials Arrival] --> B[Verify Ground Level and Stability]
    B --> C{Is Ground Level & Firm?}
    C -- Yes --> D[Stack Materials Safely]
    C -- No --> E[Prepare Ground]
    D --> F[Provide Fencing and Lighting]
    F --> G[Maintain Clear Gangways]
    G --> H[Perform Regular Safety Checks]

**Always align stacking practices with site safety plans and IS code requirements for optimal safety.

Protective Barrier Requirements per IS 13430

• Clause 8: Erect barriers to cordon off areas with potential risk of structural collapse.
• Clause 7.4: Remove or bend any protruding nails to avoid injuries.
• Barriers should be:
  • Strong enough to prevent unauthorized entry.
  • Clearly visible with appropriate markings.
  • Adequately supported to resist impact and collapse.

Typical Design Criteria:

Safety Protocols:

• Immediately barricade hazardous zones.
• Use visible warning signs and lighting when necessary.
• Conduct routine inspections and maintenance of protective barriers.

flowchart LR
    A[Risk of Collapse Identified] --> B[Install Protective Barrier]
    B --> C[Remove or Bend Protruding Nails]
    B --> D[Proper Support of Barrier]
    D --> E[Limit Unauthorized Access]
    E --> F[Routine Barrier Inspection]

Refer to IS 3696 (Scaffold Safety) and IS 3764 (Excavation Safety) for detailed barrier design and load requirements.

Protective Equipment Guidelines under IS 13430 (Clause 9)

Key Safety Provisions:

• Electrical Work (Clause 9.7.5):

  • Use insulating mats, gloves, sleeves, and tools designed for electrical safety.
  • Workers must remove all conductive items such as rings, watches, and keys.

• Welding Safety (Clause 9.4):

  • Provide welders with protective eye shields.

• General Safety Measures:

  • Remove or bend exposed nails to prevent injuries (Clause 7.4).
  • Barricade areas at risk of structural failure (Clause 8).

Electrical PPE Summary Table

flowchart TD
    A[Worker on Live Electrical System]
    A --> B[Wear Insulated Gloves and Sleeves]
    A --> C[Stand on Insulating Mats]
    A --> D[Use Insulated Tools]
    A --> E[Remove Metal Jewelry]

Note: Consult IS 3696, IS 3764, and IS 4081 for comprehensive safety requirements on scaffolding, excavation, and blasting respectively.

Hoisting Equipment Safety and Load Guidelines (Clause 9.7)

Primary Requirements:

• Mechanical Fitness: All hoisting machines, tackles, attachments, anchorage points, and supports must be constructed of sound materials, mechanically robust, and free from defects (Clause 9.7.1a).
• Rope Standards: Ropes must be strong, durable, and free from faults (Clause 9.7.1b).
• Safe Working Load (SWL):
  • SWL must be determined by approved procedures for all hoisting equipment and accessories (chains, hooks, shackles, swivels, blocks) (Clause 9.7.2).
  • All equipment must display the SWL clearly.
  • Machines with variable SWLs should show all applicable load ratings and conditions.
  • Loading beyond SWL is prohibited except during testing.

Safety Practices (Clause 9.7.5):

• When working near energized electrical installations, use insulating mats, gloves, sleeves, and tools.
• Workers should avoid wearing conductive items.

Typical Engineering Formulas:

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

  • Common Factor of Safety ranges from 5 to 7 for ropes and chains.

• Rope Strength Verification: Check diameter and material against manufacturer specs and IS standards.

Hoisting Components Diagram

graph LR
A[Hoisting Machine] --> B[Wire Rope]
A --> C[Chains, Hooks, Shackles]
A --> D[Anchorage & Supports]
B --> E[Load]
C --> E
D --> E

Summary: Clause 9.7 of IS 13430 mandates that hoisting equipment be mechanically sound, defect-free, and clearly marked with SWL. Proper safety gear is mandatory near electrical work, and strict adherence to SWL limits is essential.