Two-part polysulphide-based sealants - Specification, Part 1: General requirements

IS 12118 (Part 1) - Introduction: Key Points & Specifications

Scope:

• Covers two-part polysulphide-based sealants: a polysulphide polymer component + curing agent mixed before use.
• Intended for normal atmospheric environments in general building applications.

Key Notes:

• Based on BS 4254:1983.
• Special conditions (large temperature/humidity variations, water pressure, potable water storage) require additional tests.
• Two parts:
  • Part 1: General requirements
  • Part 2: Methods of tests

Sampling (Clause 1.3, Table A-1):

Conformity (Clause 3.2, Table A-3):

• A lot is conforming if all test results meet specified requirements.

Rounding Off (Clause 0.5):

• Follow IS 2-1960 for rounding numerical test results to match specified significant figures.

flowchart LR
    A[Two-Part Sealant Components] --> B[Mixing Before Application]
    B --> C[Curing at Ambient Temperature]
    C --> D[Rubber-like Solid Formation]
    D --> E[Use in Normal Atmospheric Environments]
    E --> F{Special Conditions?}
    F -- Yes --> G[Additional Tests Required]
    F -- No --> H[Standard Use]

This summarizes the introduction and sampling requirements for IS 12118 Part 1.

IS 12118 Part 1: Scope - Key Points & Specifications

Scope Overview:

• Covers two-part polysulphide-based sealants for general building applications.
• Sealants consist of:
  • Component A: Polysulphide polymer.
  • Component B: Curing agent.
• Mixed before application; cures at ambient temperature to a rubber-like solid.
• Based on BS 4254:1983.
• Intended for normal atmospheric environments.
• Special conditions (extreme temp/humidity, water pressure, potable water contact) require additional testing.

Sampling & Conformity

• Lot conformity: All test results on composite samples must meet specifications to declare conformity.

Additional Notes

• Final test values must be rounded off as per IS 2:1960.
• Part 2 of the standard details methods of tests.

flowchart LR
    A[Two-Part Polysulphide Sealant] --> B[Component A: Polymer]
    A --> C[Component B: Curing Agent]
    B & C --> D[Mix Before Application]
    D --> E[Cures to Rubber-like Solid at Ambient Temp]
    E --> F[Used in General Building Applications]
    F --> G{Special Conditions?}
    G -- Yes --> H[Additional Testing Required]
    G -- No --> I[Use as per Standard]

For detailed test methods and performance criteria, refer to IS 12118 Part 2.

IS 12118 Part 1: Grades of Sealants

• Two Grades Covered:
  • Pouring Grade: For horizontal joints; flows to form a smooth, level surface at ambient temperature.
  • Gun Grade: For vertical/inclined joints; resists slumping and maintains profile.

Key Specifications

Important Notes

• Gun Grade Sealant Slump Limit: ≤ 1.0 mm vertical displacement.
• Pouring Grade: Designed for ease of leveling in horizontal joints.
• Test Methods: Refer IS 12118 Part 2, Clause 2 for slump and flow tests.

flowchart LR
    A[Sealant Grades] --> B[Pouring Grade]
    A --> C[Gun Grade]
    B --> D[Horizontal Joints]
    B --> E[Flows to smooth surface]
    C --> F[Vertical/Inclined Joints]
    C --> G[Slump ≤ 1.0 mm]
    C --> H[No protrusion horizontally]

IS 12118 Part 1: Selection of Material - Key Points & Tables

1. Material Requirements (Clause 5.1):

• Materials must satisfy criteria in 5.1.1 to 5.1.7.
• Testing methods are detailed in Part 2 of IS 12118.

2. Gun Grade Sealant (Clause 2.2):

• Sealant must be gun-grade, i.e., no appreciable slumping at ambient temperature regardless of joint orientation.

3. Sampling & Testing (Clause 1.3 & 3.2):

• Number of packages for testing depends on lot size as per Table 1 (not fully provided here).
• Lot conformity requires all test samples to meet specifications.
• Refer to Table A-3 for number of tests and conformity criteria.

Typical Table Format for Sampling (Example):

(Exact values per IS 12118 Table 1)

Summary Checklist for Material Selection:

• Confirm gun-grade property (no slump).
• Verify compliance with clauses 5.1.1 to 5.1.7.
• Conduct sampling as per lot size (Table 1).
• Test all samples per Part 2 methods.
• Declare lot conforming only if all tests pass.

flowchart TD
    A[Start: Material Selection] --> B{Is Sealant Gun Grade?}
    B -- Yes --> C[Check Clauses 5.1.1 to 5.1.7]
    C --> D{Pass All Tests?}
    D -- Yes --> E[Accept Material]
    D -- No --> F[Reject Material]
    B -- No --> F

For full tables and test methods, refer to IS 12118 Part 1 & Part 2 documents.

IS 12118 Part 1: Test Conditions Summary

Key Specifications for Test Conditions

• Sealant Cure:

  • Sealant cures at ambient temperature and humidity per manufacturer instructions (Clause 3.1).
  • Primer systems must be applied as recommended for specific substrates.

• Sample Handling:

  • Referee samples must bear purchaser and vendor seals.
  • Store in cool, dry place agreed upon by purchaser and vendor (Clause 2.3).

• Storage & Mixing:

  • Components must be mixable to compliant sealant anytime before expiry under package-stated storage (Clause 4.2).

• Testing Material:

  • Tests use material from unopened containers only (Clause 4.1).

Practical Notes

flowchart TD
    A[Unopened Container] --> B[Mix Components]
    B --> C{Within Expiry Date?}
    C -- Yes --> D[Test Sealant]
    C -- No --> E[Reject Sample]
    D --> F[Sealant Cures at Ambient Conditions]
    F --> G[Apply Primer if Recommended]

This ensures consistent, reliable testing aligned with IS 12118 Part 1 requirements.

IS 12118 Part 1: Test Requirements Summary

Key Clauses & Specifications

• Composite Sample Testing (Clause 3.1):
  All specified characteristics must be tested on a composite sample representing the lot.

• Referee Sample (Clause 2.3):

  • Must bear seals of purchaser & vendor.
  • Stored in cool, dry place agreed by both parties for dispute resolution.

• Shelf Life & Mixing (Clause 4.2):
  Components must be mixable into compliant sealant anytime before expiry under recommended storage.

Sampling Scale (Clause 1.3, Table A-1)

Summary Diagram: Sampling & Testing Flow

flowchart TD
    A[Lot of Packages] --> B[Select Sample Size per Table A-1]
    B --> C[Form Composite Sample]
    C --> D[Test All Specified Characteristics]
    D --> E{Conforms to Standard?}
    E -- Yes --> F[Accept Lot]
    E -- No --> G[Use Referee Sample for Dispute]

Use this framework to ensure compliance with IS 12118 Part 1 testing requirements.

IS 12118 Part 1 - Marking & Packaging Specifications

Marking (Clause 6.1 & 6.1.1)

• Sealants shall bear the manufacturer's name or trade-mark.
• Sealants may also carry the BIS Standard Mark, indicating compliance under BIS inspection and quality control.

Packaging & Labeling (Clause 7.1)

Each package must clearly indicate:

• Manufacturer's name or trade-mark
• Weight of components
• Instructions for use and storage (including primer system)
• Type and grade of sealant
• Date of manufacture
• Date of expiry

Conformity (Clause 3.2)

• Lot conformity is declared only if all test results meet the standard's requirements.

Summary Table for Marking & Packaging

This ensures traceability, compliance, and user guidance as per IS 12118 Part 1.

flowchart TD
    A[Sealant Package] --> B[Mark Manufacturer Name/Trade-mark]
    A --> C[Mark BIS Standard Mark (optional)]
    A --> D[Indicate Weight]
    A --> E[Instructions for Use & Storage]
    A --> F[Type & Grade of Sealant]
    A --> G[Date of Manufacture]
    A --> H[Date of Expiry]

For licensing and use of the Standard Mark, contact BIS offices listed in the standard.

IS 12118 Part 1 — Packing: Key Points

Sampling of Packages (Clause 1.3 & Table A-1.3)

The number of packages to be selected from a lot depends on lot size:

• Sampling must be random (see IS 4905-1968 for random sampling methods).

Packing Specifications (Clause 7.1)

Each package must clearly indicate:

• Manufacturer’s name or trademark
• Weight of components
• Instructions for use and storage (including primer system)
• Type and grade of sealant
• Date of manufacture
• Date of expiry

Summary Diagram of Packing & Sampling Process

flowchart TD
    A[Lot of Packages] --> B[Determine Lot Size]
    B --> C{Lot Size Range}
    C -->|Up to 25| D[Select 2 Packages]
    C -->|26 to 50| E[Select 3 Packages]
    C -->|51 to 150| F[Select 5 Packages]
    C -->|151 and above| G[Select 8 Packages]
    D & E & F & G --> H[Random Selection per IS 4905-1968]
    H --> I[Check Package Markings & Instructions]

This ensures quality control and traceability in sealant packaging.

IS 12118 Part 1 – Sampling Key Points

1. Scale of Sampling (Clause 1.3, Table A-1)

2. Sampling Procedure (Clause A-2.1)

• From each selected package, take approximately equal quantities using a suitable sampling instrument.
• Mix thoroughly to form a composite sample.
• Composite sample quantity must be sufficient for triplicate tests for all requirements.

3. Random Selection (Clause A-1.3.1)

• Packages must be selected randomly.
• Follow procedures as per IS 4905:1968 for random sampling to ensure unbiased selection.

flowchart TD
    A[Lot of Packages] --> B[Select Sample Size per Table A-1]
    B --> C[Randomly Select Packages (IS 4905)]
    C --> D[Take Equal Quantity from Each Package]
    D --> E[Mix to Form Composite Sample]
    E --> F[Perform Triplicate Tests]

Summary: Use Table A-1 to determine sample size, select packages randomly, mix equal quantities to form composite samples, and test in triplicate for reliable results.

IS 12118 Part 1: Sampling of Two-Part Polysulphide Based Joint Sealants

Key Points from Clause 8.1 & Appendix A:

• Sampling procedure is detailed in Appendix A to ensure material conformity.
• Samples must be representative of the batch.
• Sampling scale and method ensure statistical reliability (refer Appendix A for details).

Sampling Scale (Appendix A):

(Note: Exact numbers may vary as per Appendix A, verify with the standard text.)

Additional Specifications:

• Sealants must be tested with primer if recommended by the manufacturer (Clause 3.1).
• Sealants are categorized into:
  • Pouring Grade: For horizontal joints.
  • Gun Grade: For vertical/inclined joints (glazing).

Summary:

• Take representative samples as per batch size.
• Include primer application during testing if specified.
• Follow manufacturer instructions for curing conditions.

flowchart TD
    A[Batch of Sealant] --> B[Determine Batch Size]
    B --> C{Batch Size}
    C -->|<=50| D[Take 2 Samples]
    C -->|51-150| E[Take 3 Samples]
    C -->|151-500| F[Take 5 Samples]
    C -->|>500| G[Take 8 Samples]
    D & E & F & G --> H[Test Samples]
    H --> I{Primer Recommended?}
    I -->|Yes| J[Apply Primer per Manufacturer]
    I -->|No| K[Proceed without Primer]
    J & K --> L[Perform Conformity Tests]

For detailed sampling procedures and test methods, always refer to Appendix A of IS 12118 Part 1.