metal chairs for office purposes Specification, Part 1: Non-revolving and non-tilting
1985 Edition

Scope of IS 3499 Part 1:

• Materials: Aluminum tubing conforming to IS 1285-1975 (HV 20 WP) or equivalent with:

  • Minimum Tensile Strength: 26 kgf/mm²
  • Minimum Elongation over 50 mm: 16%

• Aluminum Tubular Frame Requirements:

  • Wall Thickness: At least 1.60 mm
  • Shape: Round or square cross-section
  • Dimensions:
    • Round tubes with outer diameter ≥ 25 mm
    • Square tubes with side length ≥ 20 mm

• Chair Classification:

  • Chairs with arms or without arms
  • Various configurations of seats and backrests

Aluminium Tubular Frame Dimension Overview

flowchart LR
    A[IS 3499 Part 1 Scope] --> B[Material: Aluminum Tubes]
    B --> C[Tensile Strength ≥ 26 kgf/mm²]
    B --> D[Elongation ≥ 16% on 50 mm]
    A --> E[Aluminum Tubular Frame]
    E --> F[Wall Thickness ≥ 1.60 mm]
    E --> G[Round Tube: OD ≥ 25 mm]
    E --> H[Square Tube: Side ≥ 20 mm]
    A --> I[Chair Classification]
    I --> J[With Arms]
    I --> K[Without Arms]
    I --> L[Various Seat & Back Types]

This section defines the structural requirements and classification criteria for fixed metal office chairs.

Material Requirements in IS 3499 Part 1:

1. Aluminium Tubes (Clause 2.7)

• Must comply with IS 1285-1975, HV 20 WP designation or an equivalent standard.
• Minimum mechanical properties:

2. Mild Steel Sheets (Clause 2.5)

• Should meet:
  • Grade 0 of IS 513-1973 or
  • Grade 0 of IS 1079-1973

3. Chair Studs (Clause 5.4)

• Made from rubber or another appropriate material.

Chair Classification (Clause 4.1):

• By presence or absence of armrests
• By different seat and backrest types

Summary Table of Materials

flowchart TD
    A[Materials for Chairs] --> B[Aluminum Tubes]
    A --> C[Mild Steel Sheets]
    A --> D[Studs]
    B --> B1[Tensile Strength ≥ 26 kgf/mm²]
    B --> B2[Elongation ≥ 16%]
    C --> C1[Grade 0 IS 513 or IS 1079]
    D --> D1[Rubber or Suitable Material]

This section summarizes the essential material specifications.

Key Dimensions for Metal Office Chairs (IS 3499 Part 1, 1985):

• Dimensions must comply with IS 3663-1981 as stated in Clause 3.1.

• Material Standard: Aluminium tubes must align with IS 1285-1975 (HV 20 WP designation).

• Mechanical Properties of Aluminium Tubes:

  • Minimum tensile strength: 26 kgf/mm²
  • Minimum elongation: 16% over 50 mm

• Chair Types (Clause 4.1):

  • Chairs can have arms or be armless
  • Various seat and backrest designs

Aluminium Tubing Mechanical Properties Summary

Reference for Dimensions:

• Refer to IS 3663-1981 for detailed chair measurements including seat height, width, depth, backrest height, and armrest height.

flowchart TD
    A[IS 3499 Part 1] --> B[Dimensions as per IS 3663-1981]
    A --> C[Material: Aluminium Tubes (IS 1285-1975)]
    C --> D[Tensile Strength ≥ 26 kgf/mm²]
    C --> E[Elongation ≥ 16%]
    A --> F[Chair Classification]
    F --> G[With Arms]
    F --> H[Without Arms]
    F --> I[Various Seat and Back Options]

For precise dimensions, users should consult IS 3663-1981.

Performance Requirements for Finishes (IS 3499 Part 1, 1985):

Wood Arm Finishes (Clause 7.2):

• Options include:
  • Wax polish
  • Transparent glossy French polish
  • Dark stain combined with polish or lacquer
  • Finish chosen based on purchaser preference

Enamel Paint Finishes (Clause 7.1.3):

• Enamels must conform to IS 151-1950, IS 2932-1974, or IS 2933-1975.
• Stoving enamels require baking at specified temperatures to form a hard, uniform coating.

Performance Testing (Clause 8.3):

• Flexibility and adhesion tests use mild steel plates 150 × 50 mm, thickness 0.315 mm.
• Tests conducted as per IS 101-1964, Clause 16.
• Acceptance criteria: No cracks, detachment, or damage under 10× magnification after bending.

Order Information (Clause 10.1):

• Purchaser must specify:
  • Finish type
  • Colour and finish details
  • Any alternate construction or finishing methods

Flexibility & Adhesion Test Summary

flowchart TD
    A[Order Details] --> B{Specify Finish}
    B -->|Wooden Arms| C[Apply appropriate polish]
    B -->|Metal Components| D[Apply enamel coatings]
    D --> E[Conduct Flexibility & Adhesion Test]
    E --> F{Pass Test?}
    F -->|Yes| G[Accept Finish]
    F -->|No| H[Reject or Refinish]

These provisions ensure finishes are both durable and visually acceptable.

Specifications for Metal Chair Components (IS 3499 Part 1):

Metal Parts (Clause 7.1):

• Must comply with relevant Indian Standards.
• Aluminium tubes to follow IS 1285-1975 (HV 20 WP).

Chair Classification (Clause 4.1):

• Based on arm presence
• Seat and backrest type variations

Assembly Components (Clause 5.0):

• Includes legs, seat frame, backrest, armrests (details in Clauses 5.1 to 5.3)

Aluminium Tube Properties Summary

Additional Notes:

• Welding electrodes and filler rods must align with relevant IS welding standards.
• Steel parts should meet IS standards for rolled steel sheets and structural steel tubes.

flowchart TD
    A[Metal Chair] --> B[Metal Components]
    B --> C[Aluminium Tubes (IS 1285)]
    B --> D[Steel Components (IS Standards)]
    A --> E[Classification]
    E --> F[With Arms]
    E --> G[Without Arms]
    E --> H[Various Seat/Back Types]
    A --> I[Assembly Components]
    I --> J[Legs]
    I --> K[Seat Frame]
    I --> L[Backrest]
    I --> M[Armrests]

This section provides a summary of component materials and classifications.

Assembly Guidelines for Metal Office Chairs (IS 3499 Part 1, 1985)

• Classification (Clause 4.1):

  • Chairs can have arms or be armless
  • Different seat and backrest designs

• Materials (Clause 2.7):

  • Aluminium tubes complying with IS 1285-1975 (HV 20 WP)
  • Mechanical properties:
    • Tensile strength ≥ 26 kgf/mm²
    • Elongation ≥ 16% on 50 mm

• Components (Clause 5.0):

  • Assembled from parts specified in Clauses 5.1 to 5.3

• Assembly Methods (Clause 6.1):

  • Welding techniques: gas, arc, resistance spot welding
  • Bolted joints

Welding and Bolting Standards

Assembly Flowchart

flowchart LR
    A[Components (Clauses 5.1-5.3)] --> B{Assembly Method}
    B -->|Welding| C[Gas/Arc/Spot Welding]
    B -->|Bolting| D[Bolted Joints]
    C --> E[Final Chair Assembly]
    D --> E

Summary: Utilize aluminium tubes per IS 1285 with required mechanical properties. Assemble chair parts using approved welding or bolting methods to ensure structural strength and safety.

Preparation and Finishing of Metal Parts (IS 3499 Part 1):

Surface Preparation (Clause 7.1.1):

• Eliminate dents, burrs, and sharp edges.
• Clean thoroughly by pickling, scrubbing, and rinsing to remove grease, rust, and mill scale.

Phosphating Treatment (Clause 7.1.2):

• Apply immediately post-pickling.
• Use Class C phosphate coating as per IS 3618-1966.
• Follow application processes detailed in IS 6005-1970.
• Employ putty (IS 110-1968) to fill surface imperfections.
• Apply aluminium primer according to IS 5660-1970.

Painting (Clause 7.1.3):

• Use enamel paints meeting IS 151-1950, IS 2932-1974, or IS 2933-1975.
• For stoving enamels, bake at prescribed temperatures to achieve a tough, uniform finish.

Metal Finishing Process Summary

flowchart TD
    A[Metal Components] --> B[Remove dents, burrs, sharp edges]
    B --> C[Pickling, scrubbing, rinsing]
    C --> D[Phosphating (Class C)]
    D --> E[Putty Filling]
    E --> F[Apply Aluminium Primer]
    F --> G[Enamel Paint Coats]
    G --> H{Stoving Required?}
    H -- Yes --> I[Bake for Hard Finish]
    H -- No --> J[Air Dry]

This process ensures corrosion resistance and a quality finish.

Testing Protocols in IS 3499 Part 1

1. Pressure Test (Clause 8.2)

• Sample: Mild steel plate, 0.315 mm thickness, prepared as per Clause 7.
• Conduct test according to IS 101:1964, Clause 15.2.
• Requirement: No exposure of bare metal surface (no ruptures or pinholes) after testing.

2. Flexibility and Adhesion Test (Clause 8.3)

• Sample: Mild steel plate, 150 × 50 mm, thickness 0.315 mm.
• Test as per IS 101:1964, Clause 16.
• Acceptance: Paint film must show no cracks, detachment, or damage under 10× magnification after bending.

3. Aluminium Tube Mechanical Properties (Clause 2.7)

• Aluminium tubes must meet IS 1285-1975 (HV 20 WP) or equivalent.

Test Summary Table

flowchart TD
    A[Sample Preparation] --> B[Pressure Test - IS 101:15.2]
    A --> C[Flexibility & Adhesion Test - IS 101:16]
    B --> D{No visible metal surface?}
    C --> E{No paint damage or cracks?}
    D -->|Yes| F[Pass]
    D -->|No| G[Fail]
    E -->|Yes| F
    E -->|No| G

These tests validate the durability and finish quality of chair components.

Packaging Guidelines per IS 3499 Part 1:

• Clause 9.1 mandates that all parts be packed to prevent damage during transportation.
• No specific packing materials or techniques are prescribed, but protection against mechanical impact, moisture, corrosion, deformation, and abrasion is essential.

Recommended Packaging Practices:

• Use cushioning materials such as foam or bubble wrap around sensitive components.
• Employ robust containers or crates suited to the weight and dimensions of parts.
• Include moisture-absorbing agents (desiccants) if components are sensitive to humidity.
• Clearly label packages with handling instructions.

Relevant Standards:

• Aluminum tubes must conform to IS 1285.
• For wooden crates, follow commercial timber classifications and standards.

flowchart LR
    A[Component Parts] --> B{Packaging}
    B --> C[Protection from Mechanical Damage]
    B --> D[Protection from Moisture]
    B --> E[Prevention of Deformation]
    C --> F[Use Cushioning Material]
    D --> G[Include Desiccants]
    E --> H[Use Sturdy Containers]

Summary: IS 3499 Part 1 requires packaging that safeguards components during transit, allowing flexibility in methods while emphasizing damage prevention.

Information to be Provided by Purchasers (IS 3499 Part 1, 1985):

Essential Details (Clause 10.1):

• Specify chair type (e.g., with or without arms, seat and backrest design).
• Indicate desired colour and finish.
• State any alternative construction or finishing methods, if applicable.

Packaging Instructions (Clause 9.1):

• Must ensure protection of components against transit damage.

Aluminium Tube Properties (Clause 2.7):

• Aluminium tubes should adhere to IS 1285-1975 HV 20 WP or equivalent.

Summary for Purchase Orders:

• Clearly detail chair type, colour, finish, and any alternative specifications.
• Confirm compliance with material standards.
• Provide packaging requirements to prevent damage.

flowchart TD
    A[Purchaser] --> B[Specify Chair Type]
    A --> C[Specify Colour and Finish]
    A --> D[Specify Alternative Methods]
    A --> E[Specify Packaging Requirements]
    B & C & D & E --> F[Supplier Order Preparation]

These instructions ensure accurate order fulfillment aligned with IS 3499 Part 1.

Marking Guidelines for Metal Chairs (IS 3499 Part 1, Clauses 11.1 & 11.1.1)

• Chairs must bear a clear manufacturer's identification mark.
• Optionally, chairs may display the ISI Certification Mark to indicate conformity with Indian Standards and ongoing ISI quality surveillance.
• Use of the ISI mark is regulated by the Indian Standards Institution (Certification Marks) Act and corresponding regulations.

Purpose of Marking:

• Identify the manufacturer
• Ensure compliance with quality and safety standards
• Facilitate traceability under the ISI certification scheme

Marking Summary Table

Additional Notes:

• Marks should be durable and legible.
• Contact ISI offices for licensing and marking procedures.

flowchart TD
    A[Metal Chair] --> B[Apply Manufacturer ID Mark]
    B --> C{Include ISI Mark?}
    C -->|Yes| D[Apply ISI Certification Mark]
    C -->|No| E[Only Manufacturer Mark]
    D & E --> F[Ensure Durability of Marking]

This ensures traceability and conformity with IS 3499 Part 1.