Cement Concrete Flooring Tiles - Specification

IS 1237 - Scope & Key Specifications for Steel Tubes for Structural Use

Scope (Summary)

• Covers steel tubes used in structural applications.
• Applies to dimensions, tolerances, mechanical properties, and testing.
• Ensures tubes meet quality for load-bearing and construction use.

Key Specifications from Clause 3.3 and Table G-3.3

Additional Notes:

• Rounding off of test results must follow IS 2:1960.
• Refer to Annex A for related standards and latest editions.
• Specific gravity and other physical properties are detailed in the code for quality control.

Visual: Particle Size Distribution Compliance

barChart
    title Particle Size Distribution (% by Mass)
    x-axis Size (micron)
    y-axis Percentage (%)
    "355 micron": 0
    "250 micron": 0-15
    "212 micron": 45+
    "212 & 180 micron": 70+
    "Passing 150 micron": 0-3

This ensures steel tubes conform to physical quality for structural safety and durability.

IS 1237 - Terminology & Key Specifications Summary

Key Terminology & Definitions

• Specific Gravity (Clause 3.3): Important for material characterization.
• Size requirements for aggregates or particles are given by mass percentage retained/passing IS sieves.

Size Requirements Table (Clause 3.3)

Rounding Off (General Clause)

• Follow IS 2:1960 for rounding test results, matching significant digits to specified values.

Sampling (Clause 15.4)

• One sample can be used for multiple tests if it doesn't affect results.

Additional Test Methods (Annexes)

• Flatness (Annex B): Use a metal ruler along diagonals; measure max gap.

• Perpendicularity (Annex C): Use a square; measure largest gap at edges.

• Straightness (Annex D): Use thread along edges; gap ≤ 1% edge length.

• Water Absorption (Annex E):

  [ \text{Water Absorption %} = \frac{M_1 - M_2}{M_2} \times 100 ]

  where (M_1) = saturated mass, (M_2) = oven-dried mass.

• Wet Transverse Strength (Annex F): Test on soaked tiles with span depending on tile size:

flowchart TD
    A[Sample Selection] --> B[Test Flatness]
    A --> C[Test Perpendicularity]
    A --> D[Test Straightness]
    A --> E[Test Water Absorption]
    A --> F[Test Wet Transverse Strength]
``

IS 1237: Key Specifications for Types of Cement Concrete Tiles

1. Tile Dimensions (Clause 7.1, Table 1)

• Thickness measured at two points ~50 mm from tile ends on fracture line.
• Thickness = average of these two measurements.

2. Wearing Layer Thickness for Double Layer Tiles (Clause 8.3.1, Table 2)

• Thickness measured as average of lowest two points on fracture line (Clause 8.3.2).

3. Terrazo Tile Chip Size (Clause 11.2)

• Purchaser should specify chip size.
• Consult manufacturer design cards for chip size and colour pattern selection.

flowchart TD
    A[Tile Type] --> B[Single Layer]
    A --> C[Double Layer]
    C --> D[Wearing Layer Thickness]
    D --> E[Plain Cement / Coloured]
    D --> F[Terrazo Tiles]
    F --> G[Chip Size ≤ 6 mm]
    F --> H[Chip Size ≤ 12 mm]
    F --> I[Chip Size ≤ 20 mm]

This summary helps select tile size, thickness, and wearing layer per IS 1237 standards.

IS 1237: Key Formulas, Tables & Specifications for Materials

1. Specific Gravity (Clause 3.3)

• Refer Table G-3.3 for specific gravity values of materials used.

2. Particle Size Requirements (Table 3)

3. Hardness (Clause 3.4)

• Grains should have a hardness of 9 Moh's scale (corundum).

4. Water Absorption (Annex E)

[ \text{Water Absorption %} = \frac{M_1 - M_2}{M_2} \times 100 ]

• (M_1) = Mass of saturated specimen (g)
• (M_2) = Mass of oven-dried specimen (g)

5. Wet Transverse Strength (Annex F)

• Span between supports depends on tile size:

• Load applied via steel rod; padding used to prevent stress concentration.

References to Related IS Codes (Annex A)

• IS 269: Ordinary Portland Cement
• IS 383: Aggregates for Concrete
• IS 2500: Sampling Inspection Procedures
• IS 8041, 8042: Rapid Hardening & White Portland Cement
• IS 12269: Portland Cement (various grades)

This summary highlights key material specifications and test methods from IS 1237 for quality assurance in construction materials, especially tiles.

IS 1237: Pigments and Aggregates Key Specifications

Pigments (Clause 5.3)

• Important: Pigments must not contain zinc compounds or organic dyes (Clause 5.3.2).

Aggregates Size Requirements (Clause 3.3)

Additional Notes

• For terrazzo tiles (Clause 11.2), chip size must be specified by purchaser; consult manufacturer design cards for chip size and color patterns.
• Pigments and aggregates must conform to physical requirements ensuring durability and aesthetics.

flowchart TD
    A[Pigments] --> B{Color}
    B -->|Black/Red/Brown| C[IS 44]
    B -->|Green| D[IS 54]
    B -->|Blue| E[IS 55 / IS 56 / IS 3574 (Pt 2)]
    B -->|White| F[IS 411]
    B -->|Yellow| G[IS 50 / IS 3574 (Pt 1)]

    H[Aggregates] --> I{Sieve Size}
    I -->|355 micron| J[Nil % Retained]
    I -->|250 micron| K[0-15% Retained]
    I -->|212 micron| L[≥45% Retained]
    I -->|212 & 180 micron| M[≥70% Retained]
    I -->|<150 micron| N[≤3% Passing]
``

IS 1237: Manufacture and Curing of Cement Concrete Flooring Tiles

Key Specifications for Manufacture (Clause 6.1)

• Tiles made from cement, natural aggregates, and coloring material (optional).
• Manufacturing methods:
  • Pressure process (with/without vacuum dewatering)
  • Vibration process (with/without vacuum dewatering)
  • Combination of pressure and vibration.
• Minimum pressure for pressure process alone: 14 N/mm².

Aggregate Size Requirements (Clause 3.3, Table G-3.3)

Curing

• Proper curing is essential for strength and durability.
• Follow standard curing practices (e.g., water curing for 7 days minimum).

Summary Diagram: Manufacturing Process

flowchart TD
    A[Raw Materials: Cement + Aggregates + Color] --> B[Mixing]
    B --> C{Manufacturing Method}
    C -->|Pressure Process| D[Apply ≥14 N/mm² Pressure]
    C -->|Vibration Process| E[Vibration with/without Vacuum]
    C -->|Combination| F[Pressure + Vibration]
    D & E & F --> G[Curing (Water curing ≥7 days)]
    G --> H[Finished Tiles]

This ensures tiles meet IS 1237 quality standards for strength and durability.

IS 1237: Dimensions and Tolerances for Cement Concrete Flooring Tiles

Key Dimensions (Clause 7.1, Table 1)

• Thickness Measurement: Average of two points ~50 mm from tile ends on fracture line (wet transverse strength test).

Aggregate Size Requirements (Clause 3.3, Table 3)

• Shape: Grains must be rounded (Clause 3.2).

Rounding Off (IS 2:1960)

• Final test results should be rounded to the same significant figures as specified values.

Summary:

• Tile size and thickness are standardized per Table 1.
• Aggregate gradation controls quality and strength.
• Thickness measured at two points; average used.
• Follow IS 2 for rounding test results.

flowchart TD
    A[Aggregate Grading] --> B[Grain Shape: Rounded]
    B --> C[Size Limits per Table 3]
    C --> D[Concrete Mix]
    D --> E[Tile Casting]
    E --> F[Tile Dimensions per Table 1]
    F --> G[Thickness Measurement at 2 Points]
    G --> H[Quality Check & Rounding (IS 2)]

This ensures dimensional accuracy and material quality per IS 1237.

Wearing Layer Thickness for Double Layer Tiles (IS 1237: Clause 8.3)

Key Specifications (Table 2 - Clause 8.3.1)

Measurement (Clause 8.3.2)

• Measure thickness at multiple points along the fracture line after wet transverse strength test.
• Minimum wearing layer thickness = arithmetic mean of the two lowest measurements.

Wear Determination Formula (Clause 1.5, G-1.5)

[ t = \frac{(W_1 - W_2) \times V_1}{W_1 \times A} ]

Where:

• ( t ) = average loss in thickness (mm)
• ( W_1 ) = initial mass (g)
• ( W_2 ) = final mass after abrasion (g)
• ( V_1 ) = initial volume (mm³)
• ( A ) = surface area (mm²)

This ensures the durability and quality of double layer cement concrete tiles per IS 1237.

IS 1237: Special Shapes and Sizes - Key Points

1. Shape and Size (Clause 3.2 & Table 3)

• Grains must be rounded.
• Size distribution of grains (percentage by mass) as per Table 3:

2. Special Shapes (Clause 7.1 & 9)

• Tiles of shapes/sizes other than standard may be manufactured if agreed between supplier & purchaser.
• Must meet all other standard requirements.

3. Thickness of Wearing Layer (Clause 8.3.2)

• For double layer tiles, measure thickness at multiple points on fracture line.
• Minimum thickness = arithmetic mean of the two lowest measurements.

Summary Diagram: Size Distribution

barChart
    title Grain Size Distribution (% by Mass)
    "355 micron" : 0
    "250 micron" : 0-15
    "212 micron" : >=45
    "212 & 180 micron" : >=70
    "Passing 150 micron" : <=3

Use this table and clauses to verify compliance for special shapes and sizes in IS 1237 tiles.

IS 1237: Colour and Texture for Flooring Tiles

Key Specifications (Clauses 11.1 & 11.2)

• Uniformity: Colour and texture must be uniform throughout the wearing layer thickness.
• No visible differences in aggregate colour, type, or distribution on the surface.
• Purchaser's role:
  • Specify colour for plain cement/coloured tiles (consult manufacturers due to limited colour range).
  • Specify chip size for terrazzo tiles; colour pattern depends on chip size and distribution.
• Colour variation: Minor shade variations may occur between batches.

Pigments (Clause 5.3)

Colouring Material Limit (Clause 6.4)

• Max 10% by mass of cement in the wearing layer.

Summary Diagram: Colour & Texture Control Process

flowchart TD
    A[Specify Tile Type] --> B{Plain or Terrazzo?}
    B -->|Plain| C[Specify Colour (Consult Manufacturer)]
    B -->|Terrazzo| D[Specify Chip Size & Pattern]
    C --> E[Uniform Colour & Texture]
    D --> E
    E --> F[Use Pigments as per IS Standards]
    F --> G[Colouring Material ≤ 10% Cement Mass]

This ensures consistent, durable, and aesthetically acceptable flooring tiles per IS 1237.

IS 1237: Physical & Mechanical Properties Summary

1. Physical Properties

Particle Size Distribution (Clause 3.3, Table G-3.3)

2. Water Absorption (Annex E)

[ \text{Water Absorption %} = \frac{M_1 - M_2}{M_2} \times 100 ]

• (M_1) = Mass of saturated specimen (g)
• (M_2) = Mass of oven-dried specimen (g)
• Specimens soaked 24h, dried at 65±1°C for 24h.

3. Wet Transverse Strength (Annex F)

• Test on 6 tiles soaked 24h.
• Span between supports depends on tile size:

• Load applied mid-span with 12mm diameter rounded steel rod/supports.
• Plywood padding (3mm thick, 20mm wide) between tile and supports/rod.

4. Surface Flatness, Perpendicularity & Straightness

• Flatness: Measured by ruler along diagonals; max gap = concavity/convexity.
• Perpendicularity: Square placed on edges; max gap measured.
• Straightness: Thread along edges; gap ≤ 1% of edge length.

Diagram: Water Absorption Test Setup

flowchart LR
    A[Soak Tile 24h in Water] --> B[Weigh Saturated Tile (M1)]
    B --> C[Oven Dry at 65±1°C for 24h]
    C --> D

IS 1237 — Testing Methods: Key Formulas, Tables & Specifications

1. Sampling & Conformity (Clause 15.4)

• Samples for one characteristic can be reused for others if no prejudice to results.
• Refer to Table 15.3 for number of samples & conformity criteria (not fully provided here).

2. Flatness of Tile Surface (Annex B)

• Use a metal ruler ≥ tile diagonal.
• Measure largest gap (concavity/convexity) along diagonals.
• Larger gap is reported.

3. Perpendicularity (Annex C)

• Use a square larger than tile side.
• Measure gap between square arm and tile edge.
• Report largest gap.

4. Straightness (Annex D)

• Connect two corners with fine thread along edges.
• Largest gap between thread and tile ≤ 1% of edge length.

5. Water Absorption (Annex E)

• Immerse tiles 24h, wipe, weigh (M1).
• Oven dry at 65±1°C for 24h, weigh (M2).
• Water absorption (%) =
  [ \frac{M_1 - M_2}{M_2} \times 100 ]

6. Wet Transverse Strength (Annex F)

• Soak tiles 24h.
• Place on two parallel steel supports with padding.
• Apply load via steel rod; span depends on tile size:

7. Particle Size Requirements (Clause 3.3)

IS 1237: Marking and Packaging Key Points

Marking (Clause 13.2, 13.2.1)

• Standard Mark (BIS Certification Mark) may be applied on each tile.
• Use of the Standard Mark is regulated by the Bureau of Indian Standards Act, 1986.
• Licensing conditions for the Standard Mark are available from BIS.

Packaging (Clause 13.2.1)

• Tiles must be packed as per usual trade practice.
• Packaging should adequately protect tiles during transport and handling.

Relevant Specifications for Quality Control (from Tables & Clauses)

• Particle Size Distribution (by mass %):

Additional Notes

• Final test values should be rounded off as per IS 2:1960.
• Packaging and marking ensure product traceability and protection.

flowchart LR
    A[Tile Manufacture] --> B[Marking with BIS Standard Mark]
    B --> C[Packaging as per trade practice]
    C --> D[Protection during transport]
    D --> E[End User]

This ensures compliance, traceability, and product integrity.

IS 1237: Sampling and Inspection Key Points

• Sampling Procedure:

  • Samples must be randomly selected from a lot (Clause 15.2).
  • Refer to IS 4905 for random sampling methods.

• Inspection Levels & Acceptance Criteria:

  • Use Inspection Level I from Table 1 of IS 2500 (Part 1).
  • Acceptable Quality Level (AQL) = 6.5% as per Table 3 of IS 2500 (Part 1).
  • Number of samples and conformity criteria depend on lot size and inspection level.

• Sample Size & Conformity (Clause 15.3):

  • Number of tiles to be tested per characteristic is defined based on lot size and AQL.
  • Lot is accepted if the number of defectives ≤ acceptance number; rejected if > rejection number.

Typical Sampling Table (from IS 2500 Part 1, simplified)

(Refer IS 2500 Part 1 for full table)

Summary Diagram: Sampling & Inspection Flow

flowchart TD
    A[Start: Lot of Tiles] --> B[Random Sampling (IS 4905)]
    B --> C[Select Sample Size (IS 2500, Level I, AQL 6.5%)]
    C --> D[Test Samples for Characteristics]
    D --> E{Number of Defectives ≤ Ac?}
    E -- Yes --> F[Accept Lot]
    E -- No --> G[Reject Lot]

Note: Always cross-check lot size and inspection level with IS 2500 for precise sample size and acceptance criteria.

IS 1237: Criterion for Conformity (Clause 15.3 & 15.4)

• Sample Size & Conformity Criterion:
  Number of sample tiles and conformity criteria follow Inspection Level I and AQL 6.5% as per IS 2500 (Part 1), Tables 1 & 3.
  This means sampling and acceptance are based on lot-by-lot inspection with a maximum allowable defective rate of 6.5%.

• Reuse of Samples (Clause 15.4):
  Samples tested for one characteristic can be used for others if no prejudice occurs in test results, avoiding fresh sampling.

Key Reference Table (IS 2500 Part 1 extract for AQL 6.5%)

(Refer IS 2500 Part 1 for detailed sample size code letters and acceptance numbers.)

Summary Diagram: Sampling & Conformity Process

flowchart TD
    A[Start: Lot of Tiles] --> B[Select Samples as per IS 2500 Level I]
    B --> C{Test Characteristic 1}
    C --> D{Pass?}
    D -- Yes --> E{Test other Characteristics?}
    D -- No --> F[Reject Lot]
    E -- Yes --> G[Test Characteristic 2 using same samples]
    E -- No --> H[Accept Lot]
    G --> I{Pass?}
    I -- Yes --> H
    I -- No --> F

Note: For detailed sample sizes and acceptance criteria, consult IS 2500 (Part 1). This ensures statistical control of quality with AQL 6.5%.