Code of practice for the application of silicone-based water repellents

IS 12054: Scope Summary

• Scope (Clause 1.1):
  This standard specifies the procedure for preparing surfaces and applying silicone-based water repellents to protect concrete and masonry.

• Key Points:

  • Focus on surface preparation before treatment.
  • Application methods for silicone-based repellents.
  • Safety warning: Operators must avoid masks that prolong solvent vapor exposure; use airline respirators in confined spaces (Clause 6.3).

• Units & Definitions (International System - SI):

  Quantity	Unit	Symbol	Definition
  Force	newton	N	1 N = 1 kg·m/s²
  Energy	joule	J	1 J = 1 N·m
  Power	watt	W	1 W = 1 J/s
  Pressure, stress	pascal	Pa	1 Pa = 1 N/m²

Summary Diagram: Application Process Flow

flowchart TD
    A[Surface Preparation] --> B[Application of Silicone Repellent]
    B --> C[Drying & Curing]
    C --> D[Inspection & Quality Check]

This standard ensures effective water repellency by proper surface prep and safe application of silicone repellents.

IS 12054 Key Information on Silicone-Based Water Repellents

1. Necessary Information (Clause 1.1 & 3.2.1)

• The standard covers surface preparation and application of silicone-based water repellents.
• Water repellents are prepared by diluting Class A or B materials with mineral spirit or xylene.

2. Mineral Spirit Specifications (Clause 3.2.1)

• Recommended solids concentration for best results: minimum 5% solids (though 3% is effective).

3. Units & Definitions (International System of Units - IS Units)

4. Safety Note (Clause 6.3)

• Do not wear a mask that prolongs solvent vapor exposure.
• In confined spaces, use airline respirators for operator safety.

flowchart LR
    A[Surface Preparation] --> B[Dilution with Mineral Spirit/Xylene]
    B --> C[Check Mineral Spirit Specs]
    C --> D[Apply Water Repellent (≥5% solids)]
    D --> E[Operator Safety Measures]

This summary ensures proper preparation, application, and safety compliance for silicone-based water repellents per IS 12054.

IS 12054: Classification & Preparation of Water Repellents

Classification (Clause 3.1.1)

Note: If surface type is unknown, use Class B.

Preparation of Water Repellents (Clause 3.2.1)

• Water repellents are prepared by diluting Class A or B materials with mineral spirit or xylene.
• Mineral spirit must conform to:
  • Minimum flash-point: 27°C
  • Boiling range: 135 to 185°C
  • Minimum Kauri-Butanol value: 34

• Effective solids concentration: Minimum 5% solids (though 3% may be effective).

Summary Formula for Preparation

[ \text{Water Repellent} = \text{Class A or B material} + \text{Mineral Spirit/Xylene (diluent)} ]

• Ensure solids ≥ 5% for best results.

flowchart TD
    A[Select Surface Type] -->|Siliceous| B[Use Class A Repellent]
    A -->|Calcareous| C[Use Class B or G Repellent]
    B --> D[Prepare by Dilution]
    C --> D
    D --> E[Use Mineral Spirit/Xylene]
    E --> F[Check Flash Point ≥ 27°C]
    E --> G[Check Boiling Range 135-185°C]
    E --> H[Check Kauri-Butanol ≥ 34]
    F & G & H --> I[Ensure ≥ 5% Solids]
    I --> J[Apply Water Repellent]

Key Takeaway: Use appropriate class repellent for surface type, dilute with specified mineral spirit/xylene, and maintain minimum

IS 12054: Test for Selection of Suitable Class of Repellents

Key Specifications & Procedures

• Clause 4.1.3: Use masonry specimens of equal dimensions for testing different repellent classes to ensure uniformity.

• Classes of Repellents:

  • Class A & B: Dilute with mineral spirit or xylene.
    • Mineral spirit specs:
      • Minimum flash-point: 27°C
      • Boiling range: 135–185°C
      • Minimum kauri-butanol value: 34
    • Recommended solids concentration: ≥ 5% for best results.
  • Class C: Dilute with water to 3% solids max to avoid sodium carbonate precipitation.
    • Water should be free from wetting agents, soluble salts, and CO₂.

Important Notes

• Avoid concentrations above 3% solids for Class C to prevent white precipitate.
• Use equal-sized masonry samples for comparative absorption and repellency tests.
• Operator safety: Use airline respirators in confined spaces (Clause 6.3).

Summary Table for Repellent Preparation

flowchart TD
    A[Select Masonry Specimens] --> B{Equal Dimensions?}
    B -- Yes --> C[Test with Class A, B, C Repellents]
    C --> D[Measure Absorption/Repellency]
    D --> E[Select Best Performing Class]

For detailed testing, always refer to the full IS 12054 clauses on specimen preparation and repellent application.

IS 12054: Preparation of Surfaces for Silicone-Based Water Repellents

Key Specifications & Procedure:

• Surface Condition:

  • Surfaces must be clean, dry, and free from dust, dirt, oil, grease, salts, and loose particles.
  • Remove any efflorescence, algae, or moss by brushing or washing.

• Surface Repair:

  • Repair cracks and voids with compatible mortar before treatment.

• Moisture Content:

  • Surfaces should be dry or slightly damp, not saturated, to ensure proper penetration of the repellent.

• Test Specimens (Clause 4.1.3):

  • Use masonry specimens of equal dimensions for selecting the suitable water repellent class by comparative treatment.

General Preparation Steps:

1. Cleaning: Mechanical brushing or water washing.
2. Drying: Allow surface to dry naturally or by forced air.
3. Repair: Fill cracks and defects.
4. Final Cleaning: Remove dust after repairs.

Note:

IS 12054 does not provide explicit formulas or tables for surface preparation but emphasizes surface cleanliness and dryness as critical for effective silicone-based water repellent application.

flowchart TD
    A[Start: Surface to be Treated] --> B{Is surface clean?}
    B -- No --> C[Clean surface (brush/wash)]
    C --> D{Is surface dry or slightly damp?}
    B -- Yes --> D
    D -- No --> E[Dry surface naturally/with air]
    D -- Yes --> F{Any cracks or defects?}
    F -- Yes --> G[Repair with compatible mortar]
    F -- No --> H[Surface ready for water repellent application]

Summary: Clean, dry, and intact surfaces ensure maximum efficacy of silicone-based water repellents per IS 12054.

IS 12054: Application of Silicone-Based Water Repellent

Key Specifications (Clause 6.3 & related)

• Operator Safety:
  • Do not wear a mask that prolongs solvent vapor exposure.
  • In confined spaces, use airline respirators.

Preparation of Repellent (Clauses 3.2.1 & 3.2.2)

Important Units (SINUITS)

Summary Formula for Repellent Preparation:

[ \text{Solids concentration} = \frac{\text{Weight of solids}}{\text{Total weight of solution}} \times 100% ]

flowchart TD
    A[Start: Select Class of Material] --> B{Class A/B or C?}
    B -->|A/B| C[Prepare with Mineral Spirit/Xylene]
    B -->|C| D[Prepare with Water (Max 3% solids)]
    C --> E[Maintain 3-5% solids, min 5% preferred]
    D --> F[Avoid >3% solids to prevent precipitate]
    E --> G[Apply Repellent with Safety Measures]
    F --> G
    G --> H[Operator uses airline respirator in confined spaces]

Note: Always ensure solvent flash points and