Plastic chairs for general office purposes

IS 13713: Scope Summary & Key Specifications for Plastic Chairs

Scope:

• Applies to plastic chairs for general office use.
• Covers materials (filled/unfilled reinforced thermoplastics & thermosetting plastics), dimensions, strength, stability, and fire testing.
• Dimensions to conform to IS 3663:1991.
• Design as per purchaser's requirement.

Key Performance Test: Rigidity of Shell (Annex B, Clause 6.2.3)

Testing Setup (Fig. 1 Summary)

• Backrest fixed on rigid surface.
• Force applied via rigid bow with rounded edges.
• Rubber pad between bow and backrest to distribute load.

Rounding Off Test Values

• Follow IS 2:1960 for rounding numerical results.
• Retain significant digits consistent with standard values.

References

• Dimensions: IS 3663:1991
• Rounding: IS 2:1960
• Plastic chair materials: reinforced thermoplastics/thermosetting plastics.

flowchart LR
    A[Test Specimen] --> B[Fixed on Rigid Surface]
    B --> C[Apply 300 N Force at Point A]
    C --> D[Force via Rounded Bow + 6mm Rubber Pad]
    D --> E[Hold for 4 Hours]
    E --> F[Measure Displacement of Point A]

This ensures chairs meet strength and rigidity requirements for safe office use.

IS 13713: Plastic Chairs for General Office Purposes — Key References & Specifications

Referenced Indian Standards (Annex A)

Key Specifications from IS 13713

• Materials: Filled/unfilled reinforced thermoplastic and thermosetting plastics.
• Dimensions: Shall conform to IS 3663:1991.
• Strength Tests: Static, fatigue, impact tests per IS 5416 (Part 1):1988.
• Test Levels: Usage-dependent, Level 4 or 5 as per Table 3 of IS 5416 (Part 1).
• Fire Testing: Flammability tested by oxygen index method per IS 13360 (Part 6/Sec 6).

Important Notes

• Chairs may carry the Standard Mark (Clause 8.2).
• Test results must be rounded per IS 2:1960.
• Design flexibility allowed as per purchaser’s requirement.

Summary Table: Strength Test Levels (from IS 5416 Part 1)

flowchart LR
    A[Plastic Chair] --> B[Material: Thermoplastic / Thermosetting]
    B --> C[Dimension: IS 3663:1991]
    B --> D[Strength Test: IS 5416 Part 1]
    D --> E[Static Test]
    D --> F[Fatigue Test]
    D --> G[Impact Test

IS 13713 - Key Specifications for Materials (Plastic Chairs)

Material Types:

• Chairs made of filled and unfilled reinforced thermoplastic and thermosetting plastics.
• Alternatives to wood due to ecological concerns.

Material Properties & Testing:

• Mechanical properties vary widely; additives improve strength.
• Fire testing per IS 13360 (Part 6/Sec 6): 1992 for flammability by oxygen index.
• Plastic decomposes into toxic gases when burnt (like wood, plywood).

Performance Requirements (Clause 6.2.1):

• Strength tests: static, fatigue, and impact per IS 5416 (Part 1): 1988.
• Test levels 4 or 5 as per Table 3 of IS 5416 (Part 1).
• No structural defects after testing.

Dimensional Standards:

• Must conform to IS 3663: 1991 (office chair dimensions).

Important Testing Setup (Rigidity of Shell - Annex B, Clause 1.1)

Summary Table: Material & Test Standards

flowchart LR
    A[Material Selection] --> B[Plastic Type: Thermoplastic / Thermosetting]
    B --> C[Additives for Strength]
    C --> D[Manufacture Chair]
    D --> E[Dimensional Check (IS 3663)]
    E --> F[Strength Tests (IS 5416)]
    F --> G[Flammability Test (IS 133

IS 13713: Plastic Chairs for General Office Purposes – Key Dimensions & Specifications

• Dimensions: Shall conform to IS 3663:1991 (Dimensions of tables and chairs for office purposes).
• Design: As desired by the purchaser, but must meet strength and stability criteria.
• Material: Filled/unfilled reinforced thermoplastics or thermosetting plastics.
• Rigidity Test (Annex B):
  • Force applied: 300 N at 300 mm height from seat base (Point A on backrest).
  • Test duration: 4 hours under load.
  • Setup includes a 6 mm thick rubber sheet between force applicator and backrest to distribute load.
• Marking: Chairs may carry BIS Standard Mark (Clause 8.2).

Summary Table: Rigidity of Shell Test Setup

Important Reference:

• IS 3663:1991 for detailed chair dimensions.
• Strength & stability test methods: IS 686 (Part 1 & 2).

flowchart LR
    A[Seat Base] -->|300 mm| B(Point A on Backrest)
    B -->|Apply 300 N force| C[Backrest]
    C --> D[6 mm Rubber Sheet]
    D --> E[Rigid Bow with Rounded Edges]

For detailed dimension tables, refer to IS 3663:1991. This standard ensures ergonomic and safety compliance for office plastic chairs.

IS 13713 - Design Requirements Summary (Clause 6.2.3 & Annex B)

Key Test: Rigidity of Shell (Annex B)

• Test Setup:

  • Specimen fixed on a rigid plane.
  • Force applied at Point A (300 mm above seat lowest point on backrest axis).
  • Force magnitude: F1 = 300 N, backward, parallel to mounting surface.
  • A 6 mm thick rubber sheet (≥10 mm projection) placed between bow and backrest to distribute load.

• Test Duration: 4 hours under constant force.

• Acceptance: Measure displacement of Point A after loading; minimal deformation indicates adequate rigidity.

Strength Testing (Clause 6.2.1)

• Conduct static, fatigue, and impact tests as per IS 5416 (Part 1): 1988.
• Test level: Usage-based, Level 4 or 5 (see Table 3 in IS 5416).
• No structural defects allowed post-test.

Dimensions

• Conform to IS 3663:1991 for office chair dimensions.

Summary Table: Rigidity Test Setup

flowchart LR
    A[Specimen fixed on rigid plane] --> B[Mark Point A at 300 mm height]
    B --> C[Apply 300 N force backward at Point A]
    C --> D[Insert 6 mm rubber sheet between bow and backrest]
    D --> E[Maintain force for 4 hours]
    E --> F[Measure displacement of Point A]
    F --> G{Displacement acceptable?}
    G -- Yes --> H[Pass rigidity test]
    G -- No --> I[Fail rigidity test]

Note: Design is purchaser-driven; materials include reinforced thermoplastics/thermosetting plastics. Fire testing and toxicity considerations also apply.

IS 13713 – Performance Requirements Summary

1. Performance Tests (Clause 6.2.1)

• Tests: Static, fatigue, and impact tests as per IS 5416 (Part 1): 1988.
• Test Levels: Level 4 or 5 depending on usage (see Table 3, IS 5416 Part 1).
• Acceptance: No structural defects after testing.

2. Sampling and Testing (Clause 6.1)

• Samples must be selected as per Clause 6.1.
• Final test values rounded off per IS 2:1960 rules.

3. Material & Dimensions

• Chairs made of reinforced thermoplastic/thermosetting plastics.
• Dimensions conform to IS 3663:1991.

Key Table Reference: IS 5416 (Part 1):1988 — Test Levels for Office Chairs

Summary Diagram: Performance Testing Flow

flowchart TD
    A[Sample Selection (Clause 6.1)] --> B[Static Test]
    B --> C[Fatigue Test]
    C --> D[Impact Test]
    D --> E{No Structural Defects?}
    E -- Yes --> F[Pass Performance Requirements]
    E -- No --> G[Fail - Reject Sample]

Note: For detailed load values and cycles, consult IS 5416 (Part 1):1988 Table 3.

IS 13713: Sampling and Testing (Clause 6.1 & 6.2)

• Sampling (6.1.1):
  Samples must be drawn randomly from the lot per IS 5416 (Part 1):1988 to ensure representativeness.

• Strength Test (6.2.1):
  Test samples undergo:

  • Static test
  • Fatigue test
  • Impact test
    as per IS 5416 (Part 1):1988.
    The test level (4 or 5) depends on usage, referring to Table 3 of IS 5416 (Part 1).
    Acceptance criteria: No structural defects post-test.

• Stability Test (6.2.2):
  Conducted per IS 5416 (Part 2):1988 to ensure the chair does not overturn.

Key Reference Table (from IS 5416 Part 1:1988 - Table 3 sample)

Summary Diagram of Testing Process

flowchart TD
    A[Random Sampling per IS 5416 Part 1] --> B[Strength Tests]
    B --> B1[Static Test]
    B --> B2[Fatigue Test]
    B --> B3[Impact Test]
    B --> C{No Structural Defects?}
    C -- Yes --> D[Pass]
    C -- No --> E[Fail]
    D --> F[Stability Test per IS 5416 Part 2]
    F --> G{Chair Overturn?}
    G -- No --> H[Pass Stability]
    G -- Yes --> I[Fail Stability]

For detailed load values and procedures, always refer to IS 5416 (Parts 1 & 2):1988 alongside IS 13713.

IS 13713: Strength, Stability & Rigidity Tests Summary

1. Strength Test (Clause 6.2.1)

• Conduct Static, Fatigue, and Impact tests per IS 5416 (Part 1):1988.
• Test levels: 4 or 5 as per Table 3, IS 5416 (Part 1) (based on usage).
• Acceptance: No structural defects after testing.

2. Stability Test (Clause 6.2.2)

• Perform stability test per IS 5416 (Part 2):1988.
• Acceptance: Chair must not overturn during the test.

3. Rigidity Test (Clause 6.2.3, Annex B)

• For backrest rigidity, apply force as per Annex B.
• Acceptance: Displacement of force application point ≤ 75 mm from original position.

Key Reference Table (Excerpt from IS 5416 Part 1:1988, Table 3 - Test Levels)

Summary Diagram: Test Flow

flowchart TD
    A[Test Sample] --> B[Strength Test (IS 5416 Part 1)]
    B -->|Pass| C[Stability Test (IS 5416 Part 2)]
    C -->|Pass| D[Rigidity Test (Annex B)]
    D -->|Pass| E[Sample Accepted]
    B -->|Fail| F[Reject Sample]
    C -->|Fail| F
    D -->|Fail| F

For detailed load magnitudes and test setups, refer directly to IS 5416 Parts 1 & 2.

IS 13713 - Strength Test Key Points

• Test Types (Clause 6.2.1):

  • Static test
  • Fatigue test
  • Impact test
    All tests follow IS 5416 (Part 1): 1988.

• Test Levels:

  • Usage-based levels 4 or 5 as per Table 3, IS 5416 (Part 1): 1988.
  • Higher levels correspond to higher load or cycles depending on application.

• Acceptance Criteria:

  • No structural defects after testing.

• Stability Test (Clause 6.2.2):

  • Conducted per IS 5416 (Part 2): 1988.
  • Chair must not overturn.

• Rigidity of Shell (Annex B):

  • Shell rigidity tests ensure deformation limits (details in IS 5416).

Typical Strength Test Parameters (from IS 5416 Part 1)

Summary Diagram of Strength Testing Process

flowchart TD
    A[Sample Preparation] --> B[Static Test]
    B --> C{Pass?}
    C -- Yes --> D[Fatigue Test]
    C -- No --> E[Reject Sample]
    D --> F{Pass?}
    F -- Yes --> G[Impact Test]
    F -- No --> E
    G --> H{Pass?}
    H -- Yes --> I[Accept Sample]
    H -- No --> E

For detailed load values and cycles, refer to Table 3 of IS 5416 (Part 1): 1988.

IS 13713 - Stability Test Overview

• Reference Standard: Stability test for chairs is as per IS 5416 (Part 2) : 1988.
• Requirement: The chair shall not overturn during the stability test.
• Test Sample: As per Clause 6.1, the sample is selected for testing.

Key Points from IS 5416 (Part 2) - Stability Test

• The test involves applying a load at a specified point to check if the chair overturns.
• The load and position depend on chair type and intended use.
• The test simulates real-life tipping scenarios.

Typical Stability Test Setup (from IS 5416 Part 2):

Summary:

• Stability test ensures user safety by preventing overturning.
• Use IS 5416 Part 2 for detailed load values and test procedure.
• If chair overturns, design must be revised to improve base dimensions or weight distribution.

flowchart LR
    A[Start Stability Test] --> B[Apply Load at Specified Point]
    B --> C{Chair Overturns?}
    C -- No --> D[Pass Stability Test]
    C -- Yes --> E[Fail - Redesign Needed]

For exact load values and test details, consult Table 2 and 3 of IS 5416 (Part 2):1988.

IS 13713 — Rigidity Test for Backrest (Clause 6.2.3 & Annex B)

Test Setup (Annex B-1)

• Mounting: Backrest fixed on a rigid, plane surface.
• Point A: Marked at 300 mm height from the lowest seat point, on backrest axis.
• Force Applied (F1): 300 N backward, parallel to mounting surface.
• Load Application: Via a rigid bow with all edges rounded.
• Rubber Pad: 6 mm thick, extends ≥10 mm beyond bow edges, placed between bow and backrest.
• Duration: Force applied continuously for 4 hours.

Acceptance Criterion

• Maximum allowable displacement of Point A: ≤ 75 mm from original position.

Summary Table: Rigidity Test Parameters

Test Principle Diagram (Simplified)

flowchart LR
    A[Backrest Mounted Rigidly]
    B[Point A at 300 mm height]
    C[Force F1 = 300 N applied backward]
    D[Rubber Pad (6mm thick)]
    E[Rigid Bow with rounded edges]
    
    A --> B
    B --> E
    E --> D
    D --> C

Note: This test ensures the backrest's structural rigidity under sustained load, simulating user pressure without excessive deformation.

Colour Fastness to Daylight (IS 13713: Clause 6.2.4)

• The plastic shell of the chair must be tested as per IS 686:1985 (Method for determination of colour fastness of textile materials to daylight).
• The minimum rating required is Standard 3 on the grey scale (where 1 = poor and 5 = excellent).

Key Points from IS 686:1985 (Colour Fastness to Daylight)

• Testing involves exposing the plastic surface to daylight or simulated daylight for a specified duration.
• The colour change is compared with a grey scale to assess fading.

Related Standards for Chair Testing (for context):

Summary:

• Colour fastness rating ≥ 3 (IS 686:1985)
• Ensures plastic chair shells resist visible fading under daylight exposure.
• Compliance ensures durability and aesthetic longevity.

flowchart TD
    A[Plastic Shell Sample] --> B[Test as per IS 686:1985]
    B --> C{Colour Fastness Rating}
    C -->|≥ 3| D[Pass: Acceptable Colour Fastness]
    C -->|< 3| E[Fail: Unacceptable Fading]

This ensures the chair's plastic maintains acceptable colour quality under daylight exposure as per IS 13713 requirements.

IS 13713: Determination of Flammability by Oxygen Index

Key Specification

• Oxygen Index (OI): Minimum required value is 17.
• Test method as per IS 13360 (Part 6/Sec 6): 1992 - "Methods of testing for plastics: Flammability by oxygen index".

Oxygen Index Concept

• Oxygen Index is the minimum concentration of oxygen, expressed as a percentage, that will support combustion of the material.
• Higher OI means better flame resistance.

Test Principle (from IS 13360 Part 6/Sec 6)

• A vertical sample is exposed to a controlled oxygen-nitrogen atmosphere.
• The oxygen concentration is varied to find the minimum oxygen level that sustains burning.

Summary Table (Typical Oxygen Index Values)

Practical Notes

• All plastic chair components must meet OI ≥ 17.
• Packaging should prevent damage during transit to maintain test validity.
• The test ensures fire safety compliance for plastic furniture materials.

flowchart LR
    A[Sample Preparation] --> B[Clamp Sample Vertically]
    B --> C[Flow Oxygen-Nitrogen Gas Mixture]
    C --> D[Ignite Sample]
    D --> E{Does Sample Sustain Burning?}
    E -- Yes --> F[Reduce Oxygen Concentration]
    E -- No --> G[Increase Oxygen Concentration]
    F --> E
    G --> E
    E --> H[Determine Minimum O2 Concentration = Oxygen Index]

References:

• IS 13713 Clause 6.2.5
• IS 13360 (Part 6/Sec 6):1992 for detailed test procedure

IS 13713 - Marking of Plastic Chairs

Key Specifications on Marking (Clause 8):

• Clause 8.1:
  All chairs must be marked with a suitable mark identifying the manufacturer.

• Clause 8.2:
  Chairs may also bear the Standard Mark, indicating compliance with IS 13713.

Additional Relevant Points:

• Marking should be durable and legible throughout the chair's service life.
• The mark helps in traceability and quality assurance.
• No specific formula or table is provided for marking in IS 13713; it is a mandatory identification requirement.

Related Standards (Annex A):

• IS 3663:1991 — Dimensions of office chairs.
• IS 686:1985 — Colour fastness testing.
• IS 13360 (Part 6/ Sec 6):1992 — Flammability testing of plastics.

Summary Table for Marking Requirements

flowchart TD
    A[Plastic Chair] --> B[Mark Manufacturer's ID]
    B --> C{Include Standard Mark?}
    C -->|Yes| D[Mark Standard Mark]
    C -->|No| E[Only Manufacturer Mark]
    D & E --> F[Ensure Durability & Legibility]

In brief: IS 13713 mandates clear manufacturer marking on plastic chairs, optionally including the Standard Mark, to ensure traceability and compliance.

IS 13713: Packaging - Key Specifications & Formulas

1. Packaging Requirements:

• All components must be packed to prevent damage during transit (Clause 6.2.5).
• Packaging should ensure protection against mechanical shocks and environmental effects.

2. Flammability: Oxygen Index

• Materials must have an Oxygen Index ≥ 17 as per IS 13360 (Part 6/Sec 6):1992.
• Oxygen Index test evaluates material flammability; higher values mean better fire resistance.

3. Packaging Material Guidelines:

• Use cushioning materials like rubber sheets (6 mm thick, projecting 10 mm beyond contact edges) to protect surfaces.
• Packaging must accommodate force application tests without damage (e.g., 300 N force on backrest for rigidity).

Summary Table: Packaging & Testing Parameters

Conceptual Illustration: Packaging Protection

flowchart LR
    A[Component] --> B[Rubber Sheet (6mm thick)]
    B --> C[Rigid Bow (Force Application)]
    C --> D[Packaging Box]
    D --> E[Transit]
    
    style B fill:#f9f,stroke:#333,stroke-width:2px
    style C fill:#bbf,stroke:#333,stroke-width:2px

Note: Packaging must consider mechanical protection and fire safety (flammability) as per IS 13713 and related IS codes (IS 13360).