Code of Practice for Magnesium Oxychloride Composition Floors
1982 Edition

Overview of Scope

This section defines the coverage of the standard concerning magnesium chloride-based floor finishes, including preparatory steps, application procedures, and corrosion protection measures for embedded metal elements.

Highlights from Metalwork Protection Clause

• Metal surfaces must be cleaned thoroughly to remove rust and loose mill scale.
• Anti-corrosive coatings include:
  • Hot applied bituminous or coal tar compositions.
  • Cold applied bitumen or coal tar solutions in volatile solvents, excluding drying oil paints.
• Preparation of coal tar coatings involves heating, addition of hydrated lime, stirring, and filler incorporation without using thinners.

Magnesium Chloride Solution Specific Gravity Table

Additional Considerations

• Concrete base water absorption test: pond water for 5 minutes; full absorption indicates excessive porosity.
• Use uncontaminated water for magnesium chloride solution preparation and cool to ambient temperature before use.

This section ensures appropriate durability and corrosion resistance and sets guidelines for solution preparation.

Key Definitions and Terms

Terminology (Clause 2.0)

• Establishes uniform meanings for flooring-related terms to ensure consistency across applications.

Metalwork Protection (Appendix A, Clause 5.11)

• Emphasizes the necessity of rust and scale-free metal surfaces.
• Specifies anti-corrosive coating applications for hot and cold techniques.
• Details coal tar coating preparation steps, forbidding the use of thinners.

Base Absorption Testing (Appendix B, Clause 6.1.2)

• Involves creating a 300 mm × 300 mm × 15 mm water reservoir on the floor.
• 0.5 pint water is poured; if fully absorbed within 5 minutes, the base is overly absorbent.

Physical Criteria (Clause 7.2.2)

Strength Benchmarks (Table 2, Clause 7.2.2)

Types of Magnesium Oxychloride Flooring (As per IS 658)

1. General Purpose Flooring (Trowel Finished)

• Constituent materials include calcined magnesite, fillers such as talc, sawdust, asbestos, fine aggregates, and magnesium chloride solution.
• Produces dense, smooth, semi-gloss surfaces.
• Commonly used in offices, hospitals, residential spaces, ship decks, railway coaches, and industrial floors.

2. Preparation of Magnesium Chloride Solution

• Dissolve magnesium chloride in clean water within a sealed container.
• Allow the solution to settle overnight; only clear solution should be employed.
• Control specific gravity according to the following:

3. Magnesium Chloride Solution Proportioning

• Add sufficient solution to just moisten the dry mix.
• Excess solution aids finishing but does not enhance strength and may be detrimental.

4. Limitations and Precautions

• Not suitable for areas with high moisture, damp conditions, or direct seawater exposure.
• A damp-proof membrane is mandatory if the base contacts the ground.

flowchart LR
    A[Dry Components: Magnesite + Fillers + Aggregates] --> B[Addition of MgCl2 Solution]
    B --> C{Consistency Check}
    C -->|Optimal| D[Apply and Trowel Finish]
    C -->|Excess| E[Weak Flooring - Avoid]
    D --> F[Dense, Smooth Surface]

This section underscores the criticality of appropriate solution specific gravity and mixing proportions for durable flooring.

Materials and Composition Highlights

Metalwork Protection (Appendix A, Clause 5.11)

• Metal parts must be free from rust and loose scale before coating.
• Use anti-corrosive coatings:
  • Hot application: Bituminous or coal tar compositions with fillers (e.g., 5% asbestine).
  • Cold application: Bitumen or coal tar solutions in volatile solvents, excluding drying oil paints.
• Preparation of coal tar involves heating to ~120°C to remove volatiles, addition of hydrated lime, stirring for 30 minutes.

Magnesium Chloride Solution Requirements (Clause 6.2.1)

• Prepare solution in sealed containers and allow impurities to settle.
• Avoid contact of solution with floor or walls during preparation.

Physical Characteristics of Mix (Clause 7.2.2)

• Initial setting time: 1 to 2 hours
• Final setting time: 3 to 6 hours

Strength Values (N/mm²):

Performance and Property Requirements (Clause 7.2.2)

Setting Times (per IS 10132-1982)

• Initial set: Between 1 and 2 hours
• Final set: Between 3 and 6 hours

Strength Criteria

Linear Dimensional Changes

• Maximum expansion: 0.15%
• Maximum contraction: 0.25%

Performance Testing Workflow

flowchart TD
    A[Sample Mix] --> B[Setting Time Test (IS 10132)]
    B --> C{Check Setting Times}
    C -->|Initial| D[1 - 2 Hours]
    C -->|Final| E[3 - 6 Hours]
    A --> F[Strength Testing]
    F --> G[Transverse and Compressive Strength]
    G --> H[Compare with Standard Values]
    A --> I[Linear Change Evaluation]

Preparation and Installation Procedures

Magnesium Chloride Solution Preparation (Clause 6.2.1)

• Dissolve magnesium chloride salt in clean water within a sealed container.
• Allow the mixture to settle overnight to clear impurities.
• Stir thoroughly after each dilution step before measuring specific gravity.
• Cool solution to ambient temperature prior to application.
• Prevent contact between solution and floor or walls during mixing.

Specific Gravity for Solution (Table 1)

Application (Clause 6.5)

• Ensure concrete base is fully dry before applying the floor finish.

Testing of Mix Samples (Clause 7.2.1)

• Collect samples from at least three different parts of the mixer.
• Blend samples uniformly prior to testing.
• Test each color separately for mottled finishes.

These steps guarantee proper bonding and long-lasting flooring.

Inspection and Testing Protocols

Inspection (Clause 7.1)

• Conduct inspections before, during, and after installation.
• Check:
  • Condition of the base
  • Metalwork protection coatings and surface cleanliness
  • Correct mixing ratios
  • Adequate compaction and finishing
  • Proper curing procedures

Metalwork Protection (Appendix A, Clause 5.11)

• Metal surfaces must be clean and free of rust and mill scale.
• Apply bituminous or coal tar coatings via hot or cold methods.
• Coal tar heating and lime addition steps must be followed without adding thinners.

Physical Property Testing (Clause 7.2.2)

• Initial setting time: 1 to 2 hours
• Final setting time: 3 to 6 hours

Strength Requirements

Surface Treatment and Maintenance Guidelines

Metalwork Protection (Clause 5.11, Appendix A)

• Metal surfaces must be cleaned to be free of rust and loose mill scale.
• Use coatings:
  • Hot application: Bituminous or coal tar compositions with fillers such as 5% asbestine.
  • Cold application: Bitumen or coal tar solutions in volatile solvents; no drying oil paints.
• Coal tar preparation includes heating to ~120°C, adding hydrated lime, stirring for 30 minutes, and forbidding thinners.

Base Absorption Testing (Appendix B)

• Construct a 300 mm × 300 mm × 15 mm reservoir on the floor.
• Pour 0.5 pint of water and observe absorption.
• Absorption within 5 minutes indicates high porosity.

Magnesium Chloride Solution Parameters (Clause 6.2.1)

• Solution preparation should ideally be done outdoors.
• Use clean water and allow solution to settle.

Surface Treatment (Clause 6.8)

• Efflorescence removed with dry steel wool.
• Wash repeatedly with warm clean water.
• Apply treatments such as a mix of double boiled linseed oil and turpentine or wax/drying oil.

Physical Properties (Clause 7.2.2)

Strength Requirements

Material Storage and Handling Instructions

General Storage (Clause 9)

• Store all materials in clean, dry, and well-ventilated spaces.
• Protect metal components from corrosion using anti-corrosive coatings (Appendix A).

Metalwork Protection (Appendix A, Clause 5.11)

• Metal surfaces must be free from rust and mill scale before coating.
• Coating options include:
  • Hot applied bituminous/coal tar compositions with fillers (e.g., 5% asbestine).
  • Cold applied bitumen or coal tar solutions in volatile solvents, excluding drying oil paints.
• Preparation involves heating coal tar to ~120°C, removing volatiles, adding hydrated lime, and stirring.

Floor Surface Preparation (Clause 8.1)

• Clean floors with warm water and mild soap free from alkali.
• Avoid soda or abrasive powders.
• Apply wax polish or drying oil after cleaning.

Magnesium Chloride Solution Preparation (Clause 6.2.1)

• Prepare solution preferably outdoors or ensure floor protection indoors.
• Maintain specific gravity according to the following:

Absorption Test (Appendix B)

• Use a 300 mm square by 15 mm deep reservoir.
• Pour 0.25 pint water.
• Absorption within 5 minutes indicates excessive porosity.

flowchart TD
    A[Material Storage] --> B[Metalwork Protection]
    B --> C[Surface Cleaning]
    B --> D[Apply Anti-Corrosive Coating]
    A --> E[Floor Surface Cleaning]
    E --> F[Wax or Oil Dressing]
    A --> G[Magnesium Chloride Solution Prep]
    G --> H[Specific Gravity Control]
    A --> I[Absorption Test]

Summary: Proper storage entails dry, clean conditions and corrosion prevention of metals.

Guidelines for Protecting Metal Components (Clause 5.11, Appendix A)

Preparation of Metal Surfaces:

• Remove all rust and loose mill scale to ensure a clean substrate.

Coating Specifications:

• Coatings must form a continuous, flexible, and waterproof film.

Types of Coatings:

• Hot applied bituminous or coal tar compositions, including fillers such as asbestine.
• Cold applied solutions of bitumen or coal tar in volatile solvents; drying oil-based paints are prohibited.

Coal Tar Coating Preparation:

Summary Table for Coating Materials

Proper surface preparation and coating application ensure long-term corrosion resistance.

flowchart TD
    A[Clean Metal Surface] --> B[Apply Hot Bituminous/Coal Tar Coating]
    A --> C[Apply Cold Bitumen/Coal Tar Solution]
    B --> D[Add Fillers for Hot Application]
    C --> E[No Drying Oil Paints Allowed]
    D --> F[Impervious, Flexible Coating]
    E --> F

This appendix secures metal longevity in magnesium oxychloride flooring systems.

Procedure to Assess Base Absorption (Clause 6.1.2, Appendix B)

Test Method:

• Select three pre-agreed locations on the concrete floor.
• Construct a reservoir measuring 300 mm by 300 mm with 15 mm depth using a suitable barrier (putty or plasticine).
• Pour 0.5 pint (approximately 237 ml) of water into each reservoir.
• Record the time.
• If the water is completely absorbed within 5 minutes, the base is deemed excessively absorbent.

Purpose:

• To verify that the base does not soak up magnesium chloride solution excessively, which may impair floor finish performance.

Test Parameters:

Additional Concerns:

• Protect floor surfaces during solution preparation.
• Maintain magnesium chloride solution specific gravity as per standards.
• Comply with physical and strength mix requirements as specified.

flowchart TD
    A[Select Three Floor Positions] --> B[Construct Reservoir (300x300x15 mm)]
    B --> C[Pour 0.5 Pint Water]
    C --> D[Start Timer]
    D --> E{Is Water Absorbed within 5 Minutes?}
    E -->|Yes| F[Base is Too Absorbent]
    E -->|No| G[Base Absorption Acceptable]

This testing ensures the longevity and reliability of the magnesium oxychloride flooring.