Glass Fibre Reinforced Plastic (GRP) Panel Type Door Shutters for Internal Use

IS 14856: Scope — Key Specifications & Formulas

1. Dimensions & Tolerances (Clause 7.1 & 7.2)

• Door shutters conform to modular sizes (Table 2).
• Modular size unit: M = 100 mm.
• Width and height examples (mm):

• Thickness of door frame rebate = 45 mm.
• Dimensional relations (Fig. 2):
  • MH = Modular height of door opening
  • MH - 10 mm = Overall height
  • MH - 95 mm = Height of shutter
  • MW = Modular width of door opening
  • MW - 10 mm = Overall width
  • MW - 100 mm = Width of shutter

2. Elastic Modulus in Bending (Clause 1.5, Annex F-4)

[ E = \frac{P L^3}{4 b d^3 D} ]

Where:

• (E) = Elastic modulus (MPa)
• (P) = Load on specimen (N)
• (L) = Distance between supports (mm) = 16 × thickness
• (b) = Breadth of specimen (mm)
• (d) = Thickness of specimen (mm)
• (D) = Deflection at load (P) (mm)

3. Water Absorption (Annex G)

[ \text{Absorption} % = \frac{W_2 - W_1}{W_1} \times 100 ]

Where:

• (W_1) = Mass before immersion (mg)
• (W_2) = Mass after 24 h immersion in distilled water (mg)

flowchart LR
    A[Modular Door Opening] --> B[Calculate Overall Dimensions]
    B --> C[Select Door Shutter Size]
    C --> D

IS 14856 Key References, Formulas & Tables Summary

1. Bending Test (Clause 1.5 & F-4)

• Support span (L):
  ( L = 16 \times d ) (thickness), accurate to ±1 mm
• Support edge radius: 1.5 to 3.5 mm
• Loading nose radius: 5 mm
• Deflection rate: 5 mm/min

Elastic Modulus in Bending:
[ E = \frac{P L^3}{4 b d^3 D} ]

Where:

• (E) = Elastic modulus (MPa)
• (P) = Load from linear portion (N)
• (L) = Support span (mm)
• (b) = Breadth (mm)
• (d) = Thickness (mm)
• (D) = Deflection (mm)

2. Water Absorption (Annex G)

• Specimen: 38 ± 0.5 mm square, thickness = sheet thickness
• Soak: 24 ± 1 h in distilled water at 23 ± 2°C
• Absorption coefficient (%):
  [ \text{Absorption} = \frac{W_2 - W_1}{W_1} \times 100 ]

Where:

• (W_1) = mass before immersion (mg)
• (W_2) = mass after immersion (mg)

3. Glass Content (Annex B)

• Use muffle furnace at 575 ± 25°C to burn resin
• Weigh specimens before and after ignition until constant mass
• Calculate glass content from weight loss

4. Tensile Strength (Annex D)

• Specimens: 5, thickness ≥ 3 mm
• Test at 27 ± 2°C, fracture in 30–90 s
• Tensile Strength (MPa):
  [ TS = \frac{L_B}{A} ]

Where:

• (L_B) = Load at break (N)
• (A) = Cross-sectional area (mm²)

5. Rounding Off (Clause Annex E)

IS 14856: Definitions - Key Formulas & Tables

1. Definitions (Clause 3.1)

• Definitions relate to door shutter components (see Fig. 1 in IS 14856 for illustrations).

2. Elastic Modulus in Bending (Clause 1.5, F-4 Calculation)

[ E = \frac{PL^3}{4bd^3D} ]

Where:

• E = Elastic modulus in bending (MPa)
• P = Load from the linear part of load-deflection curve (N)
• L = Distance between supports = 16 × thickness (mm)
• b = Breadth of specimen (mm)
• d = Thickness of specimen (mm)
• D = Deflection corresponding to load P (mm)

3. Water Absorption (Annex G)

[ \text{Absorption coefficient (%)} = \frac{W_2 - W_1}{W_1} \times 100 ]

Where:

• W₁ = Mass before immersion (mg)
• W₂ = Mass after 24h immersion in distilled water (mg)

4. Glass Content Determination (Annex B)

• Uses muffle furnace at 575 ± 25°C to burn resin.
• Glass content calculated by repeated heating, cooling, and weighing until mass stabilizes.

5. Standard Sizes of Door Shutters (Clause 7.2, Table 2)

• M = 100 mm modular size
• 'D' = Door, 'S' = Single shutter, 'T' = Double leaf shutter.
• Overall height = Modular height - 10 mm
• Shutter height = Modular height - 95 mm
• Overall width =

IS 14856: Key Formulas and Specifications for Materials

1. Elastic Modulus in Bending (Clause 1.5, F-4)

Calculated from the initial linear portion of the load-deflection curve in a 3-point bending test.

[ E = \frac{P L^3}{4 b d^3 D} ]

• E = Elastic modulus in bending (MPa)
• P = Load from straight part of curve (N)
• L = Distance between supports = 16 × thickness (mm)
• b = Breadth of specimen (mm)
• d = Thickness of specimen (mm)
• D = Deflection at load P (mm)

2. Water Absorption (Annex G)

[ \text{Absorption coefficient (%)} = \frac{W_2 - W_1}{W_1} \times 100 ]

• W1 = Mass before immersion (mg)
• W2 = Mass after 24 ± 1 h immersion in distilled water at 23 ± 2°C (mg)
• Specimen size: 38 ± 0.5 mm square, thickness = sheet thickness

3. Tensile Strength (Annex D, D-4)

[ TS = \frac{L_B}{A} ]

• TS = Tensile strength (MPa)
• L_B = Load at break (N)
• A = Cross-sectional area (mm²)

Specimens: Thickness ≥ 3 mm, tested at 27 ± 2°C, fracture time 30-90 s.

4. Glass Content (Annex B)

• Heat specimens at 575 ± 25°C to burn off resin; weigh residue for glass content.
• Use muffle furnace, desiccator, and precise weighing (±10 mg).

5. Test Setup Details (Clause 1.5)

• Supports radius: 1.5 to 3.5 mm
• Loading nose radius: 5 mm
• Deflection rate: 5 mm/min
• Specimen thickness ≥ 1.5 mm, minimum 3 mm edge distance from indentor

flowchart LR
    A[Spec

IS 14856 - Composition and Additives: Key Points

1. Fillers and Additives Content (Clause 5.5.3)

• Fillers and additives shall not exceed 10% by weight of the isophthalic resin.

2. Glass Content Determination (Annex B)

• Use a muffle furnace at 575 ± 25°C to burn out resin.
• For samples without fillers/colouring agents: residue is glass fibre.
• For samples with fillers/colouring agents: residue includes glass + fillers; wash and filter to isolate glass.
• Specimen mass ≥ 5 g, rectangular with face area ≥ 400 mm², shorter edges ≥ 12 mm.
• Weigh crucible and specimen repeatedly until mass stabilizes (±0.01 g).

3. Elastic Modulus in Bending (Clause 1.5, Annex F-4)

[ E = \frac{PL^3}{4bd^3 D} ]

Where:

• E = Elastic modulus (MPa)
• P = Load from linear portion of load-deflection curve (N)
• L = Distance between supports (mm)
• b = Breadth of specimen (mm)
• d = Thickness of specimen (mm)
• D = Deflection corresponding to load (mm)

4. Water Absorption (Annex G)

[ \text{Absorption} % = \frac{W_2 - W_1}{W_1} \times 100 ]

Where:

• W1 = Mass before immersion (mg)
• W2 = Mass after 24 ± 1 h immersion in distilled water at 23 ± 2°C (mg)

Summary Table: Composition Limits

flowchart TD
    A[Isophthalic Resin] --> B[Additives & Fillers ≤ 10%]
   

IS 14856: Key Construction & Design Specifications

1. Polyurethane Foam (Clause 5.9)

• Density: Minimum 32 kg/m³
• Thickness: 4 mm less than shutter thickness, ±0.5 mm tolerance

2. Door Shutter Sizes (Clause 7.2, Table 2)

• Width & height in mm; bracketed values are from finished floor level.
• 'D' = Door, 'S' = Single Shutter, 'T' = Double Leaf Shutter.
• Door frame rebate thickness = 45 mm.

3. Elastic Modulus in Bending (Clause 1.5, Table F-3)

[ E = \frac{P L^3}{4 b d^3 D} ]

Where:

• (E) = Elastic modulus (MPa)
• (P) = Load in straight portion of load-deflection curve (N)
• (L) = Distance between supports (mm)
• (b) = Breadth of specimen (mm)
• (d) = Thickness of specimen (mm)
• (D) = Deflection at load (P) (mm)

4. Water Absorption (Annex G)

[ \text{Absorption %} = \frac{W_2 - W_1}{W_1} \times 100 ]

• (W_

IS 14856 - Sizes and Types of Door Shutters

Key Specifications (Clause 7.2 & 7.1.1)

1. Modular Sizes of Door Shutters (Table 2)

• Notation:
  • First number = Width in modules (M = 100 mm)
  • Last number = Height in modules
  • 'D' = Door, 'S' = Single shutter, 'T' = Double leaf shutter
• Sizes other than modular allowed if agreed.

2. Component Dimensions & Tolerances (Table 1)

3. Frame & Shutter Dimensions (Fig. 2 Summary)

• Thickness of door frame rebate: 45 mm
• Overall height of shutter: MH - 10 mm
• Height of shutter: MH - 95 mm

IS 14856: Locations of Fittings and Accessories (Clause 8)

• Hinges:

  • Each door shutter shall have 3 hinges (unless purchaser specifies otherwise).
  • Locations:
    • One hinge at the center of the shutter height.
    • Two hinges placed 200 mm from the top and bottom edges of the shutter.
  • Hinges fixed where blocks are provided inside the frame, indicated by a profile depression (see Fig. 1).

• Other Fixtures:

  • Must be installed only where blocks are provided (refer Fig. 1 for block sizes and locations).

Key Dimensions from Table 2 (Clause 7.2)

• Values in brackets indicate height from finished floor level.
• Modular size (M) = 100 mm.
• Thickness of door frame rebate = 45 mm.

Dimensional Relations (from Fig. 2)

Where:

• MH = Modular Height of door opening
• MW = Modular Width of door opening

flowchart TB
    A[Door Shutter]

IS 14856: Surface Quality Requirements & Related Specifications

Surface Quality (Clause 6.5)

• Finished surface must be buffed and polished to ensure smoothness.
• Testing area should be free from mechanical damage.

Test Specimens (Clause 1.5 & Annex D)

• Thickness ≥ 1.5 mm for hardness tests; ≥ 3 mm for tensile tests.
• Minimum 3 mm distance from indentor point to specimen edge.
• Number of specimens: 5.
• Specimens must be smooth, edges free from imperfections, no overheating during cutting.

Indicating Device (Clause 1.2)

• Dial with 100 divisions.
• Each division = 0.0076 mm penetration depth.

Tensile Strength Calculation (Annex D-4)

[ \text{Tensile Strength (TS)} = \frac{L_B}{A} ]

Summary Table: Specimen Requirements

flowchart LR
    A[Raw Material] --> B[Cut Specimens]
    B --> C{Thickness}
    C -->|≥1.5 mm| D[Hardness Test]
    C -->|≥3 mm| E[Tensile Test]
    D --> F[Buff & Polish Surface]
    E --> F
    F --> G[Testing]
    G --> H[Calculate TS or Hardness]

Note: Follow IS 2:1960 for rounding off test results.

IS 14856 – Tests on Door Shutters (Summary of Key Requirements & Formulas)

1. Dimensions and Squareness Test (IS 4020 Part 2)

• Dimensional tolerance: ±5 mm for nominal width & height.
• Squareness: Deviation ≤ 1 mm per 500 mm length.
• Thickness uniformity: Variation ≤ 0.8 mm between any two points.

2. Impact Indentation Test (IS 4020 Part 8)

• Door shutters must withstand 5 impacts on both sides without significant permanent deformation or deterioration.
• Test includes the shutter with hangings, fixings, and fastenings.

3. Buckling Test (IS 4020 Part 9)

• Residual deformation after unloading (15 min) ≤ 5 mm.
• Initial deflection during test ≤ 50 mm.
• No deterioration allowed.

Other Tests (IS 4020 Parts 1-16)

• General flatness, local planeness, edge loading, shock resistance, and slamming tests as per IS 4020.

Quick Reference Table

flowchart LR
    A[Door Shutter] --> B[Dimension & Squareness Test]
    A --> C[Impact Indentation Test]
    A --> D[Buckling Test]
    B -->|Tolerance ±5 mm| E[Width & Height]
    B -->|Deviation ≤1 mm/500 mm| F[Squareness]
    C -->|5 impacts both sides| G[No permanent deformation]
    D -->|Residual deflection ≤5 mm| H[No deterioration]
    D -->|Initial deflection ≤50 mm| I[Deflection Limit]

This ensures door shutters meet durability and dimensional accuracy per IS 14856 & IS 4020.

IS 14856 - Marking: Key Specifications & Related Test Procedures

1. Marking (Clause 12.2.1 & 12.2.2)

• Standard Mark: Door shutters may be marked with the BIS Standard Mark.
• License for Use: Governed by Bureau of Indian Standards Act 1986. Conditions for license use available from BIS.

2. Related Test Specimen & Calculation Formulas

• (TS): Tensile strength (MPa)
• (L_B): Load at break (N)
• (A): Cross-sectional area (mm²) | | Bending Strength & Elastic Modulus (Clause 1.5, Annex F) | Specimen thickness (d), length between supports (L = 16d), loading nose radius 5 mm | [ E = \frac{P L^3}{4 b d^3 D} ]
• (E): Elastic modulus (MPa)
• (P): Load on straight part of curve (N)
• (L): Support span (mm)
• (b): Breadth (mm)
• (d): Thickness (mm)
• (D): Deflection (mm) | | Glass Content Determination (Annex B) | Specimen mass ≥ 5 g, heated at 575±25°C in muffle furnace | Weigh before/after resin burn-off to calculate glass content. | | Water Absorption (Annex G) | 38±0.5 mm square specimens, thickness as sheet | [ \text{Absorption %} = \frac{W_2 - W_1}{W_1} \times 100 ]
• (W_1): Mass before immersion (mg)
• (W_2): Mass after immersion (mg) | | Fire Retardancy (Annex H) | Specimens tested per standard fire tests | Follow BIS fire retardancy test procedures. |

IS 14856 - BIS Certification Mark Key Points

Certification Mark (Clause 12.2)

• Governed by BIS Act 1986 and related rules.
• Licence for Standard Mark use is granted by BIS to manufacturers.
• Details available from Bureau of Indian Standards.

Important Test Procedures & Formulas

• (E) = Elastic modulus (MPa)
• (P) = Load (N)
• (L) = Support span (mm)
• (b) = Breadth (mm)
• (d) = Thickness (mm)
• (D) = Deflection (mm) | | Water Absorption (Annex G) | Specimen immersed 24h in water at 23 ± 2°C |
  [ \text{Absorption} % = \frac{W_2 - W_1}{W_1} \times 100 ]
  Where:
• (W_1) = Weight before immersion
• (W_2) = Weight after immersion | | Fire Retardancy (Annex H) | Tests specified for fire retardant properties | Refer to BIS for detailed procedure |

Summary Table of Referenced IS Standards (Annex A)

IS 14856: List of Referenced Indian Standards (Annex A)

Key Notes:

• Use the latest editions of these standards as they are subject to revision.
• For test procedures and calculations (e.g., glass content in laminates), refer to Annex B of IS 14856.
• Rounding off values must comply with IS 2:1960 rules.

Example: Glass Content Determination (Annex B Summary)

If you need specific formulas or test procedures, please specify!

Determination of Glass Content (IS 14856)

Key Equipment (Annex B):

• Weighing balance (±10 mg accuracy)
• Muffle furnace
• Crucible (preheated at 575 ± 25°C)
• Desiccator

Specimen Requirements:

• Mass ≥ 5 g
• Rectangular shape with face area ≥ 400 mm²
• Shorter edge ≥ 12 mm

Procedure Summary (Clause B-3):

1. Drying: Heat crucible + specimen at 105-110°C until constant mass (W₂).
2. Ashing:
   • For samples without filler/colouring: Heat at 575 ± 25°C until glass residue is white.
   • For samples with filler/colouring: Heat to burn resin, then wash residue to isolate glass.

Key Formula for Glass Content:

Where:

• W = Mass of empty crucible
• W₂ = Mass of crucible + dried sample
• W₃ = Mass of crucible + glass residue (no filler)
• W₁ = Mass of glass residue after washing (with filler)

Acceptable Glass Content (Table 3, Clause 10.1.1):

• Minimum 25% glass content by weight.

flowchart TD
    A[Prepare specimen] --> B[Dry at 105-110°C until constant mass (W2)]
    B --> C{Sample type?}
    C -->|No filler| D[Heat at 575°C until glass residue white (W3)]
    C -->|With filler| E[Heat at 575°C to burn resin, wash residue (W1)]
    D --> F[Calculate % glass content: (W3-W)/(W2-W)*100]
    E --> F[Calculate

Determination of Barcol Hardness (IS 14856)

Specimen Requirements (Clause 1.5):

• Thickness ≥ 1.5 mm
• Minimum distance of 3 mm from indentor point to specimen edge
• Report hardness as arithmetic mean of multiple specimens

Barcol Hardness Test Setup (Fig. 3)

• Components: Plunger, Upper Guide Nut, Lock Nut, Spring Sleeve, Lower Plunger Guide, Case & Frame Assembly
• Indentor presses into specimen surface; hardness reading taken directly

Procedure Summary:

• Use Barcol impressor as per diagram
• Take multiple readings on specimen
• Average values for final hardness

Additional Notes:

• Test specimens must be flat and smooth for accurate indentation
• Barcol hardness scale ranges typically from 0 to 100

Related Important Formulas from IS 14856 (for other tests):

flowchart LR
    A[Specimen Preparation] --> B[Barcol Hardness Test]
    B --> C[Indentor Penetration]
    C --> D[Read Hardness Value]
    D --> E[Average Multiple Readings]
    E --> F[Report Barcol Hardness]

For precise testing, follow IS 14856 Annex C Table 3 and Clause 1.5 strictly.