Specification for Industrial Safety Helmets (Bilingual)

IS 2925 Part B: Scope Summary

• Scope: Covers specifications for mild steel welded wire fabric used in concrete reinforcement.
• Definitions (Clause 2.0): Establishes terms relevant to welded wire fabric.
• S Hook (Clause 2.3):
  • Overall height: 100 mm
  • Overall width: 50 mm
  • Material: Steel rod of 10 or 12 mm diameter
• Sample Selection (Clause 1.1): Samples to be selected as per Clause 9.1 (sampling procedure).
• Clearance Above Head (B-2): Specifies minimum clearance for reinforcement placement.
• Standard Mark (Clause 10.1.2): Use governed by BIS Act, 1986; licensing details available from BIS.

Key Specifications Table: S Hook Dimensions

This standard ensures quality and uniformity in welded wire fabric for reinforced concrete applications.

IS 2925 Part B: Terminology and Definitions (Clause 2.0)

• Scope: Clause 2.0 defines terms used in the standard related to fire fighting helmets and equipment.
• Key Reference: Wooden Headform as per IS 7692:1975 for helmet testing (Clause 2.1 D-2.1).
• Purpose: Establishes uniform terminology for consistent interpretation and application.

Important Specifications & References:

Notes:

• No direct formulas or tables are provided in Clause 2.0.
• Terminology forms the basis for understanding test methods and specifications in later clauses.
• Refer to IS 7692 for detailed wooden headform dimensions and properties.

flowchart LR
    A[IS 2925 Part B] --> B[Clause 2.0: Terminology]
    B --> C[Wooden Headform]
    C --> D[IS 7692:1975]
    B --> E[Technical Committee]
    E --> F[Experts from Fire Services, Defense, Industry]

For detailed definitions, consult the full text of Clause 2.0 and related appendices.

IS 2925 Part B focuses on fire fighting equipment — Materials and Components specifications are critical for durability and performance.

Key Specifications for Materials and Components:

• Corrosion Resistance: Tested as per Appendix A (Clause 3.3) — metal parts undergo corrosion resistance testing to ensure longevity.
• Heat Resistance: As per Clause 8.6 and Appendix J, components must resist heat without separation, distortion, or softening.
• Sampling & Conformity: Clause 9 details sampling procedures and acceptance criteria to ensure quality compliance.

General Material Requirements:

• Use corrosion-resistant metals (e.g., stainless steel, brass, or suitably coated steel).
• Components must maintain mechanical integrity under fire exposure.

Testing Methods Summary:

For detailed formulas or tables, refer to the specific appendices mentioned in the standard.

flowchart LR
    A[Materials Selection] --> B[Corrosion Resistance Test]
    B --> C{Pass?}
    C -- Yes --> D[Heat Resistance Test]
    C -- No --> E[Reject Material]
    D --> F{Pass?}
    F -- Yes --> G[Use in Fire Fighting Equipment]
    F -- No --> E

Summary: Ensure materials pass corrosion and heat resistance tests per IS 2925 Part B Appendices for reliable fire fighting components.

IS 2925 Part B: Key Dimensions and Sizes

• S Hook (Clause 2.3):

  • Overall height: 100 mm
  • Overall width: 50 mm
  • Material: Steel rod of 10 or 12 mm diameter

• Block for Gauge Support (Clause 2.4):

  • Height: 1 m
  • Length: 1 m
  • Width: 0.6 m
  • Mass: 1 tonne
  • Bedding: On dry sand over a solid floor

• Headband Size Tolerance (Clause 4.1.1):

  • Permitted tolerance: ±10 mm
  • Measurement tools: Fixed ring gauge, expanding gauge (metal), or appropriate headform

Summary Table

flowchart TD
    A[S Hook] -->|Dimensions| B[100 mm H, 50 mm W]
    A -->|Material| C[10 or 12 mm steel rod]
    D[Support Block] -->|Dimensions| E[1m × 1m × 0.6m]
    D -->|Mass| F[1 tonne]
    D -->|Bedding| G[Dry sand on solid floor]
    H[Headband] -->|Tolerance| I[±10 mm]
    H -->|Measurement| J[Fixed/Expanding gauge or headform]

This concise summary ensures compliance with IS 2925 Part B for dimensions and sizes.

IS 2925 Part B: Design and Construction Requirements (Summary)

• Block Support (Clause 2.4):

  • Concrete or monolithic block to support gauge and headform.
  • Minimum dimensions:
    • Height = 1 m
    • Length = 1 m
    • Width = 0.6 m
  • Mass: 1 tonne
  • Bedding: On dry sand over a solid floor for stability.

• Material & Construction (Clause 1.1):

  • Helmets must meet strict criteria for material quality, workmanship, finish, and performance to protect against falling objects and industrial hazards.

• Heat Resistance (Clause 8.6):

  • Helmets must resist heat per Appendix J test method.
  • Shell must not separate, distort, or soften under test conditions.

• Sampling & Conformity (Clause 9):

  • Defines sampling procedures and acceptance criteria to ensure consistent quality.

Key Specification Table: Block Dimensions

This block acts as a stable base for testing helmet impact resistance per IS 2925 standards.

IS 2925 Part B: Workmanship and Finish - Key Points

Workmanship (Clause 6.1)

• Surface finish: Helmet surface must be smooth, free from burrs.
• Edges: All sharp edges must be removed to ensure proper fitting contact.
• Metal parts: Rivets and metal fittings must be smooth, without sharp or rough projections.

Finish Requirements

• Corrosion resistance: Tested per Appendix A (Clause 3.3) to ensure durability of metal parts.
• Heat resistance: Shell must not separate, distort, or soften under heat test as per Appendix J (Clause 8.6).

Impact Test Setup (Clause 2.25)

• Woollen headform with helmet brim partially cut at back.
• Mass = 2.25 kg suspended by cord length = 50 cm.
• Mass dropped freely from height = 30 cm (two trials).
• Cable clip must remain intact post-test.

Summary Table: Workmanship & Finish

flowchart LR
    A[Helmet Surface] --> B{Smooth & Burr-free?}
    B -- Yes --> C[Pass Workmanship]
    B -- No --> D[Reject]
    A --> E{Edges Sharp?}
    E -- No --> C
    E -- Yes --> D
    F[Metal Parts] --> G{Smooth & No Projections?}
    G -- Yes --> C
    G -- No --> D
    H[Impact Test] --> I{Cable Clip Intact?}
    I -- Yes --> C
    I -- No --> D

This ensures helmet quality per IS 2925 Part B.

IS 2925 Part B: Marking and Labelling Key Points

Marking Requirements (Clause 10.1 & 10.1.1)

• Mandatory markings on helmet shell or harness:
  • Manufacturer's name or trademark
  • Range/Size of helmet
• Optional marking:
  • BIS Certification Mark (ISI Mark) under BIS Act, 1986

Labelling Instructions (Clause 11.1)

Each helmet must have a clear, indelible label (on shell or securely attached) stating:

• Fit: "For adequate protection this helmet shall fit or be adjustable closely to the required size."
• Impact: "This helmet is made to absorb some of the energy of a blow by partial destruction of its component parts and even though damage may not be readily apparent any helmet subject to severe impact should be replaced."
• Alteration: "To maintain full efficiency of this helmet there shall be no alteration to the structure of the helmet or its component parts."

Summary Table of Marking Elements

This ensures traceability, user awareness, and compliance with safety standards under IS 2925 Part B.

IS 2925 Part B: Performance Requirements and Tests - Key Points

1. Mass Requirement (Clause 7.1)

• Maximum mass of helmet (without attachments/peak): 400 g
• If mass > 400 g, label must indicate mass to nearest 35 g

2. Electrical Resistance Test (Clause 8.4, Appendix G)

• Method specified in Appendix G
• Ensures electrical insulation properties of helmet materials

3. Heat Resistance Test (Clause 8.6, Appendix J)

• Test per Appendix J
• Helmet shell must not separate, distort, or soften under heat exposure

4. Corrosion Resistance Test (Clause 11.1, Appendix A)

• Method described in Appendix A
• Ensures durability of metal parts against corrosion

Summary Table:

If you need specific test procedures or formulae from the appendices, please specify!

IS 2925 Part B — Sampling and Criteria for Conformity

Key References:

• Clause 9.1: Sampling and conformity criteria follow IS 9695:1980 (Methods for sampling of helmets).
• Clause 8.6: Heat resistance test per Appendix J — shell must not separate, distort, or soften.

Sampling Procedure (per IS 9695:1980):

• Samples are selected from production batches.
• Sample size depends on batch size (refer to IS 9695 tables).
• Random sampling ensures representativeness.

Criteria for Conformity:

• All tested samples must meet mechanical, thermal, and dimensional requirements.
• Heat resistance: No shell deformation or separation after test.
• Failure in any sample may lead to batch rejection or retesting.

Typical Sampling Table (Example):

Note: Actual values per IS 9695:1980.

Summary:

• Follow IS 9695:1980 for sampling.
• Test samples for all specified properties.
• Heat resistance per Appendix J must show no damage.
• Use acceptance criteria to accept/reject batches.

flowchart TD
    A[Production Batch] --> B[Random Sampling per IS 9695]
    B --> C[Test Samples for Properties]
    C --> D{Pass All Tests?}
    D -- Yes --> E[Batch Accepted]
    D -- No --> F[Batch Rejected or Retested]

For detailed tables and procedures, refer directly to IS 9695:1980 and Appendix J of IS 2925.

IS 2925 Part b: Certification Marking Key Points

• Clause 10.1 (Marking Requirements):
  Each helmet (shell and harness) must be legibly and indelibly marked with:

  • Manufacturer's name or trade-mark
  • Range/Size of helmet

• Clause 10.1.1 (BIS Certification Mark):
  Helmets may bear the ISI Certification Mark indicating conformity to IS 2925.

• Clause 10.1.2 (Use of Standard Mark):
  Use of the Standard Mark is regulated by the BIS Act, 1986. Licensing conditions for manufacturers are governed by BIS rules.

• Clause 8.6 (Heat Resistance):
  Helmets must pass heat resistance tests (Appendix J) without shell separation, distortion, or softening.

Summary Table of Marking Requirements

Notes:

• Certification mark use requires a valid BIS license.
• Marking ensures traceability and conformity.
• Heat resistance compliance is critical for safety.

flowchart LR
    A[Helmet] --> B[Mark Manufacturer Name/Trade-mark]
    A --> C[Mark Range/Size]
    A --> D{BIS License?}
    D -->|Yes| E[Apply ISI Certification Mark]
    D -->|No| F[No Certification Mark]

For detailed licensing conditions, contact the Bureau of Indian Standards directly.

IS 2925 Part B: Instructions for Use and Maintenance

Key Points from Clauses:

• Clause 10.1.2:

  • Use of Standard Mark follows BIS Act 1986 and related rules.
  • Licence conditions for Standard Mark use are governed by BIS.

• Clause 2.1 (Burner Operation):

  • Flame height: 150 mm.
  • Test flame by inserting 0.71 mm dia copper wire, length ≥ 100 mm, positioned 50 mm above burner.
  • Wire should melt within 6 seconds for satisfactory operation.

• Clause 11.1 & Appendix A:

  • Method for testing corrosion resistance of metal parts is provided (details in Appendix A).

Practical Summary for Use and Maintenance:

Maintenance Tips:

• Regularly verify burner flame height and wire melting test to ensure burner efficiency.
• Follow corrosion resistance testing methods (Appendix A) to check metal parts durability.
• Use Standard Mark only under BIS licensing conditions.

flowchart LR
    A[Start Burner] --> B[Set valve for 150 mm flame]
    B --> C[Insert 0.71 mm copper wire 50 mm above burner]
    C --> D{Wire melts in ≤ 6 sec?}
    D -- Yes --> E[Burner operation satisfactory]
    D -- No --> F[Adjust valve or service burner]

This ensures safe and efficient burner operation and compliance with IS 2925 Part B.

IS 2925 Part B: Corrosion Resistance Testing Method (Appendix A, Clause 11.1)

Key Specifications:

• Test Solution:
  • 5 parts sodium chloride (NaCl)
  • 0.5 parts distilled water (by mass)
• Temperature: 25°C to 35°C (room temperature)
• Duration: Continuous spraying for 24 hours
• Post-Test Procedure:
  • Wash specimens in clean running water
  • Dry thoroughly
  • Inspect for corrosion signs (no corrosion should be observed)

Important Notes:

• Metal parts must be inherently corrosion-resistant or treated accordingly.
• Helmets for underground mines must not contain aluminium, magnesium, or their alloys due to corrosion risk.

Summary Table:

flowchart TD
    A[Prepare Specimens] --> B[Spray with NaCl Solution (24 hrs)]
    B --> C[Wash with Clean Water]
    C --> D[Dry Specimens]
    D --> E{Inspect for Corrosion}
    E -- No corrosion --> F[Pass]
    E -- Corrosion found --> G[Fail]

This method ensures durability and safety of metal parts in helmets, especially for harsh environments like underground mines.

IS 2925 Part b: Flammability Resistance Test Method Key Points

• Test Method: As per Appendix F of IS 2925 Part b.
• Test Procedure:
  • Apply flame to the helmet shell material.
  • Remove flame after a specified duration.
  • Observe the shell for burning or emission of flame.
• Acceptance Criteria:
  • The shell shall not continue to burn or emit flame for more than 5 seconds after flame removal (Clause 8.3 & 3.2).
• Material Behavior:
  • No flaming should persist beyond 5 seconds.
  • Shell should not separate, distort, or soften under heat (Clause 8.6, Appendix J for heat resistance).
• Sampling & Conformity: Refer Clause 9 for sampling plan and acceptance criteria.

Summary Table: Flammability Resistance

flowchart LR
    A[Apply Flame to Shell] --> B[Remove Flame]
    B --> C{Burning continues?}
    C -- Yes --> D[Check if > 5 sec]
    C -- No --> E[Pass]
    D -- > 5 sec --> F[Fail]
    D -- ≤ 5 sec --> E[Pass]

This ensures helmet shells meet fire safety by limiting flame duration and maintaining structural integrity.

IS 2925 Part B — Electrical Resistance Test for Helmet Shell

Key Specifications:

• Leakage Current Limit: ≤ 3 mA (Clause 8.4)
• Test method as per Appendix G (Clause 8.4)

Method Summary (Appendix G):

• Measure electrical resistance of helmet shell using a suitable insulation resistance tester or megger.
• Apply a specified voltage (typically 500 V DC) across the helmet shell.
• Measure leakage current; it must not exceed 3 mA to ensure electrical safety.

Typical Formula:

[ I = \frac{V}{R} ] Where:

• (I) = Leakage current (A)
• (V) = Test voltage (V)
• (R) = Electrical resistance (Ω)

To ensure (I \leq 3,mA), resistance (R) should satisfy: [ R \geq \frac{V}{3 \times 10^{-3}} ]

Practical Table (Example for 500 V test voltage):

Summary:

• Use 500 V DC insulation tester.
• Ensure leakage current ≤ 3 mA.
• Resistance should be ≥ 166 kΩ at 500 V.

flowchart LR
    A[Apply DC Voltage (500 V)] --> B[Measure Leakage Current]
    B --> C{Is Leakage Current ≤ 3 mA?}
    C -- Yes --> D[Pass: Helmet Shell Safe]
    C -- No --> E[Fail: Helmet Shell Unsafe]

This ensures electrical safety compliance per IS 2925 Part B.

IS 2925 Part B: Heat Resistance Test Method - Key Points

Method of Testing Heat Resistance (Clause 2.1 & 8.6)

• The helmet shell is subjected to a heat source as per Appendix J.
• The shell must not separate, distort, or soften during or after exposure.
• Heat exposure simulates real fire conditions to ensure helmet integrity.

Appendix J (Summary of Heat Resistance Test)

• Test Temperature: Typically around 250°C to 300°C (refer to exact Appendix J for precise value).
• Exposure Duration: Usually 4 minutes of direct flame or heat.
• Acceptance Criteria: No visible deformation, melting, or loss of structural integrity.

Sampling and Conformity (Clause 9)

• Sampling follows a defined plan (e.g., batch-wise).
• Helmets passing the heat resistance test qualify for conformity.

Typical Heat Resistance Test Setup (simplified):

flowchart LR
    A[Helmet Shell] --> B[Exposed to Flame/Heat Source (Appendix J)]
    B --> C{After Exposure}
    C -->|No Deformation| D[Pass]
    C -->|Deformation/Softening| E[Fail]

Summary Table:

Refer to Appendix J of IS 2925 Part B for exact test conditions and apparatus details.