Foam Concentrate for producing mechanical foam for fire fighting - Specification (Amalgamating IS 4989 (Part 1):1985, (Part 2): 1984, (Part 3):1987

IS 4989 - Scope Summary & Key Specifications

• Scope (Clause 1.2):
  Foam concentrates covered are suitable only for top application on fires. Base injection systems for storage tanks require special provisions.

• Referenced Standards:

  IS No.	Title
  5 : 1994	Colours for ready mixed paints and enamels
  123 : 1962	Ready mixed paint, brushing, finishing, semi-gloss
  554 : 1999	Pipe threads for pressure-tight joints
  1783 : 1993	Steel drums (galvanized and ungalvanized)
  ...	...

• Key Physical & Chemical Properties (Table 1, Clause 3.3):

  Property	Range/Requirement	Notes
  pH	6 - 7.5 (3% & 6%)	Annex A
  Specific Gravity	1.13 - 1.18 (3% & 6%)	Annex B
  Miscibility with water	Must be miscible	Annex C
  Pour Point	0°C	Annex D
  Sludge Content	Max 0.5% original, 1.0% conditioned	Annex E
  Spreading Coefficient	Minimum +3 (AFFF)	Annex F

• Foam Concentrate Centrifuge Speed (Clause 2.2):
  [ \text{rev/min} = \frac{423 \times \text{RCF}}{d} ] Where:

  • RCF = 500 to 600
  • d = diameter (cm) between tube tips in rotation

• Film Formation Test Setup (Annex H):

  • Mild steel tray: 60 cm × 60 cm × 15 cm height
  • Stainless steel wire mesh drum: 45 cm height, 20 cm diameter, 180 μm sieve size
  • Nozzle and equipment per Annex G

Visual: Foam Application Scope

flowchart TD
    A[Foam Concentrates] --> B[Top Application Only]
    B --> C[Special Base Injection for Storage Tanks]
    A

IS 4989: Types of Foam Concentrates & Key Specifications

Types of Foam Concentrates (Clause 1.1)

Key Characteristics (Clause 3.3)

• Foam concentrates must meet physical, chemical, and fire performance requirements as per Tables 1 & 2.
• Testing methods specified in Annex G (foam generation) and Annex K (advanced tests).
• Foam expansion ratio: up to 20 times (low expansion foam).

Important Notes

• Foam solution preparation (Clause F-1.1):
  Use distilled water with surface tension ≥ 70 mN/m.
  Prepare solution in a 100 ml volumetric flask using a pipette for accuracy.

Summary Formula for Foam Solution Preparation:

[ \text{Foam Solution} = \text{Water} % + \text{Foam Concentrate} % ]

Example for Type 3: [ 97% \text{ water} + 3% \text{ concentrate} ]

flowchart LR
    A[Foam Concentrate Type] --> B[Mix with Water]
    B --> C[Foam Solution]
    C --> D[Foam Generation (Annex G)]
    D --> E[Fire Performance Testing (Tables 1 & 2)]
    E --> F[Compliance Check]

This ensures proper foam quality and fire suppression efficiency per IS 4989.

IS 4989: Characteristics and Requirements of Foam Concentrates

1. Key Physical & Chemical Properties (Table 1 at 27 ± 5°C)

2. Centrifuge Speed for Testing (Clause 2.2)

[ \text{rev/min} = \frac{423 \times RCF}{d} ]

• RCF = 500 to 600 (Relative centrifugal force)
• d = diameter (cm) between opposite tube tips during rotation

3. Sampling (Clause 9.2)

• Random container selection per IS 4905
• Equal sample amounts mixed for composite conformity test

4. Testing Notes

• Annex K tests are expensive; perform after other tests pass.
• Foam generation method: Annex G.

flowchart TD
    A[Foam Concentrate Batch] --> B[Random Container Selection (IS 4905)]
    B --> C[Equal Sample Collection]
    C --> D[Composite Sample Preparation]
    D --> E[Physical & Chemical Tests (Annex A-F)]
    E --> F{Pass?}
    F

IS 4989: Packaging and Storage – Key Points

Packaging & Sampling (Clause 9.2)

• Containers selected randomly per IS 4905 method.
• Equal samples from each container mixed for composite conformity test.

Chemical & Physical Properties (Table 1 at 27 ± 5℃)

Storage Specifications

• Container Material: Stainless steel (SS 304) or as per manufacturer (Clause 5.3).
• Storage Environment: Dry, well-ventilated, no direct sunlight (Clause 5.1).
• Marking on Containers (Clause 6.1):
  • Manufacturer name/trademark
  • Foam type: PF, FFFP, AFFF
  • Sea water compatibility
  • Quantity (litres)
  • Manufacture date & batch no.
  • Net/gross mass (kg)
  • Storage instructions: avoid sunlight, freeze protection up to -20°C

Summary Diagram: Storage Requirements

graph LR
A[Storage Place] --> B[Dry & Well Ventilated]
A --> C[No Direct Sunlight]
D[Containers] --> E[SS 304 or Manufacturer Spec]
D --> F[Proper Marking per Clause 6.1]

This ensures foam concentrate quality and compliance during storage and transportation.

IS 4989 - Test Methods: Key Formulas, Tables & Specifications

Sampling (Clause 9.2)

• Random selection of containers per batch using IS 4905 method.
• Equal amounts from each container mixed for composite conformity test.

Table 1: Chemical & Physical Properties @ 27 ± 5℃

Fire Performance (Table 2)

IS 4989: Certification and Marking Key Points

Certification Marking (Clause 6.2 & 6.2.1)

• Products may bear the BIS Standard Mark.
• Use of the Standard Mark is governed by the Bureau of Indian Standards Act, 1986.
• Licence conditions for using the Standard Mark are provided by BIS.
• Manufacturers must comply with BIS rules for certification and marking.

Fuel for Fire Performance Testing (Clause 7)

• Fuel: n-heptane or commercial heptane mixture.
• Specifications:
  • Distillation range: 84°C to 105°C
  • Max difference between initial and final boiling point: ≤ 10°C
  • Density/Specific gravity: 0.70 to 0.80 at 27 ± 5°C

Sampling for Type Test (Clause 9.2)

• Containers selected randomly per IS 4905.
• Equal samples mixed to form a composite sample for conformity testing.

Table 1: Chemical & Physical Properties (at 27 ± 5°C)

Summary Diagram: Certification & Testing Flow

flowchart TD
    A[Manufacturer] --> B[Apply for BIS Licence]
    B --> C[Product Tested per IS 4989]
    C --> D{Test Results}
    D -->|Pass| E[Grant BIS Mark Licence]
    D -->|Fail| F[Reject/Retest]
    E --> G[Mark Product with BIS Standard Mark]

For detailed licence conditions and marking procedures, consult the BIS Act and Rules or

IS 4989: Fuel for Fire Performance Testing - Key Points

Fuel Specifications (Clause 7)

• Fuel: n-heptane or commercial heptane mixture
• Distillation range: 84°C to 105°C
• Max difference (initial-final boiling point): ≤ 10°C
• Density/Specific Gravity: 0.70 to 0.80 at 27 ± 5°C

Fire Test Procedure (Clause 2.2.1)

• Ignite n-heptane within 30 seconds of pouring.
• Burn for 30 seconds.
• Generate foam and direct at the back of the tank just above the water/fuel surface for 180 seconds.
• Stop foam application after 180 seconds.
• Record time for fire control and complete extinction.

Equipment & Conditions

• Foam making nozzle capacity: 7.5 L/min (Clause 7.5, Fig. 2)
• Foam generation setup: 100 L pressure vessel, pressure gauge, mild steel pipe, adjustable stand (Fig. 3)
• Water: Potable, at 27 ± 5°C
• Tank: Clean, rust-free, no dents
• Safety: Fireproof suits, gloves, helmet with face shield mandatory

Film Formation Test (Annex H, Table 2)

• Tray: Mild steel, 60 cm × 60 cm × 15 cm height
• Drum: Stainless steel wire mesh (180 µm IS sieve), 45 cm height, 20 cm diameter
• Nozzle: As per Annex G specifications

Summary Table: Fuel Properties

flowchart TD
    A[Pour n-heptane] --> B[Ignite within 30s]
    B --> C[Burn for 30s]
    C --> D[Apply foam for 180s]
    D --> E[Stop foam]
    E --> F[

IS 4989: Foam Generation Equipment & Procedure Key Points

Foam Making Nozzle (Clause G-1.1, 3.1)

• Capacity: 7.5 L/min at 7 kgf/cm² pressure.
• Setup: Nozzle horizontal, 3 ± 0.3 m from foam collector top edge.
• Procedure:
  • Fill pipework with foam solution.
  • Adjust nozzle pressure to 7 kg/cm².
  • Discharge foam for 30 ± 5 s to stabilize.
  • Collect foam in vessel, weigh empty (m₁) and full (m₂).

Expansion Calculation (Clause 3.1)

[ E = \frac{V \times \rho_w}{m_2 - m_1} ]

• E: Foam expansion (dimensionless)
• V: Volume of collecting vessel (litres)
• m₁: Mass of empty vessel (kg)
• m₂: Mass of foam-filled vessel (kg)
• ρ_w: Density of water (approx. 1 kg/L)

Spreading Coefficient (Clause F-4)

[ S_{a/b} = r_b - r_a - r ]

• (S_{a/b}): Spreading coefficient (dynes/cm)
• (r_b): Surface tension of cyclohexane (standard value)
• (r_a): Surface tension of foam solution
• (r): Interfacial tension between foam solution and cyclohexane

Foam Generating Equipment (Fig. 3)

• Pressure vessel (100 L)
• Pressure gauge at nozzle inlet
• High-pressure rubber tube & mild steel pipe
• Adjustable stand for nozzle

Surface & Interfacial Tension Measurement (Clause 3.3)

• Use fresh solutions and cleaned platinum ring.
• Measure interfacial tension by placing aqueous solution below cyclohexane.
• Avoid contact of platinum ring with oil during setup.

Foam Collector Vessel (Fig. 4)

• Drainage pot, transport tube (30-50 mm length, 6-8 mm bore)
• Discharge outlet closure
• Measuring cylinder: 100 ml with 5 ml least measure

flowchart TD
    A[Foam Solution Tank] -->|Pipework full of solution| B[

IS 4989: Type Tests Summary

1. Sampling (Clause 9.2)

• Containers are randomly selected per IS 4905.
• Equal amounts from each container mixed for a composite sample.
• Single conformity test performed on composite sample.

2. Chemical & Physical Properties (Table 1, Clause 3.3)

3. Fire Performance Requirements (Table 2, Clause 1.1)

IS 4989: Physical & Chemical Property Tests Summary

Sampling (Clause 9.2)

• Random containers selected per IS 4905.
• Equal samples mixed for composite conformity test.

Table 1: Key Physical & Chemical Properties at 27 ± 5℃

pH Determination (Annex A)

• Aged sample conditioning:
  • Heat 500 ml sample at 50 ± 1℃ for 24h.
  • Cool to 0 ± 1℃ for 24h.
  • Return to 27 ± 5℃ for testing.
• Measure pH on original and aged samples.

Centrifuge Speed (Clause 2.2)

[ \text{rev/min} = \frac{423 \times \text{RCF}}{d} ]

• RCF = 500 to 600
• d = tube diameter in cm

Surface Tension & Spreading Coefficient (Annex F)

• Applicable for AFFF 3% and 6%.
• Spreading coefficient ≥ +3 (minimum).

IS 4989: Fire Performance Tests - Key Formulas, Tables & Specifications

1. 25% Drainage Time Calculation (Clause 4.1, Annex J)

• Formula:

[ \text{Drainage volume at 25%} = \frac{\text{Drainage pan volume}}{4 \times \text{Foam expansion}} ]

• Example:

• Procedure:
  • Start stopwatch immediately after pouring foam.
  • Measure foam expansion.
  • Record drainage volume over time.
  • Time to drain 50 ml is the 25% drainage time.

2. Fire Performance Requirements (Table 2, Clause 1.1)

3. Test Equipment & Setup

• Foam Making Nozzle: 7.5 l/min capacity (Clause 7.5)
• Drainage Pan

IS 4989: Surface and Interfacial Tension Determination (AFFF Foam Concentrate)

Key Specifications:

• Foam Solution (F-1.1): Prepared at recommended concentration in distilled water with surface tension ≥ 70 mN/m.
• Cyclohexane (F-1.2): Purity ≥ 99% (AR grade), used for interfacial tension and spreading coefficient.
• Temperature: 27 ± 5°C for all measurements.

Surface Tension Measurement (Ring Method)

1. Calibrate tensiometer; clean glassware and platinum ring thoroughly.
2. Submerge platinum ring in foam solution.
3. Slowly lower platform, applying torsion to keep ring at zero dial.
4. Record dial reading at detachment point → Surface tension (dynes/cm or mN/m).

Interfacial Tension Measurement

1. After surface tension, carefully layer cyclohexane on foam solution.
2. Avoid ring contact with cyclohexane.
3. Wait 6 ± 1 minutes.
4. Measure tension using ring method → Interfacial tension (dynes/cm).

Centrifuge Speed Formula (Clause 2.2)

[ \text{rev/min} = \frac{423 \times \text{RCF}}{d} ]

• RCF = 500 to 600
• d = diameter between tube tips (cm)

Summary Table (Conceptual)

flowchart TD
  A[Prepare Foam Solution (F-1.1)] --> B[Calibrate Tensiometer]
  B --> C[Measure Surface Tension (Ring Method)]
  C --> D[Add Cyclohexane

IS 4989: Determination of Expansion and Drainage Time

Key Formulas

1. Foam Expansion (E):

[ E = \frac{V}{(m_2 - m_1)} ]

• (V) = volume of collecting vessel (litres)
• (m_1) = mass of empty vessel (kg)
• (m_2) = mass of vessel filled with foam (kg)
• Foam solution density = 1.0 kg/l (assumed)

2. 25% Drainage Volume Calculation:

[ \text{Drainage Volume} = \frac{\text{Volume of drainage pan}}{\text{Expansion}} \times 0.25 ]

• Example:
  • Volume of drainage pan = 1600 ml
  • Expansion = 8
  • 25% Drainage volume = (\frac{1600}{8} \times 0.25 = 50 \text{ ml})

Procedure Summary

• Fill drainage pan with foam, start stopwatch immediately.
• Measure foam expansion.
• Collect drained liquid volume from 20 ml to 80 ml.
• Plot time (s) vs drained volume (ml).
• Time corresponding to 25% drainage volume (e.g., 50 ml) = 25% drainage time.

Equipment Setup (Fig. 4)

• Drainage Pot (A)
• Transport Tube (C): 30-50 mm length, 6-8 mm bore
• Discharge Outlet Closure (D)
• Measuring Cylinder (E): 100 ml with 5 ml least measure

flowchart LR
    A[Start foam discharge] --> B[Fill drainage pan]
    B --> C[Start stopwatch]
    C --> D[Collect drained liquid volume]
    D --> E[Plot time vs volume]
    E --> F[Determine 25% drainage time]

Note: Control drainage outlet to allow liquid flow but prevent foam escape for accurate drainage time measurement.

IS 4989: Film Formation Test for AFFF Foam Concentrates (3% & 6%)

Key Specifications (Annex H & Clause 2.1)

• Fire Tray: Mild steel, 60 cm × 60 cm × 15 cm height.
• Strainer Drum: Stainless steel wire mesh (180 µm sieve), 45 cm height, 20 cm internal diameter, closed bottom.
• Foam Application: Use nozzle at 7 kg/cm² pressure, foam generation rate ~7.5 L/min.
• Test Procedure:
  1. Fill tray with 5 cm water.
  2. Pour 2 L commercial heptane over water surface.
  3. Generate foam gently to fill tray.
  4. Place strainer drum on foam surface.
  5. After 3 min, lower a lighted torch near (not touching) the liquid surface inside drum.
  6. Pass Criteria: No sustained ignition of the surface film (self-extinguishing flashes ignored).

Centrifuge Speed Formula (Clause 2.2)

[ \text{rev/min} = \frac{423 \times RCF}{d} ]

• RCF: 500 to 600 (relative centrifugal force)
• d: diameter between tube tips in cm

Chemical & Physical Properties (Table 1, Clause 3.3)

Summary Diagram of Film Formation Test Setup

flowchart TD
    A[Fill Tray with 5 cm Water] --> B[Pour 2 L Heptane]
    B --> C[Generate Foam (Nozzle at 7 kg/cm²)]
    C --> D[Place Strainer Drum on Foam]
    D --> E[Wait 3 Minutes]
    E --> F[Lower Lighted Torch

IS 4989: Burn Back Test Key Points

Burn Back Pot Specifications (Clause 2.3.1)

• Material: Steel
• Thickness: 1.5 mm (nominal)
• Diameter: 120 ± 5 mm
• Depth: 100 ± 2 mm

Test Procedure (Clause 2.3.2)

• Fill ~1 litre fuel in the burn back pot.
• After fire tank extinction + 60 s, place pot centrally in the tank; foam surface and pot edges should be level.
• Ignite the pot with a torch.
• Allow burning in still air; flames must be vertical.
• Visually record 25% burn back time (time for 25% of fire test tank to be under fire).
• Also record:
  • Indoor/outdoor test
  • Foam-solution temperature
  • Control time
  • Extinction time
  • 25% burn back time

Purpose

• Measures thermal stability and sealability of foam blanket.
• Control time and extinction time are quality indicators.

Summary Table

flowchart TD
    A[Fill 1L fuel in burn back pot] --> B[Place pot on foam after 60s of fire extinction]
    B --> C[Ignite pot with torch]
    C --> D[Allow burn in still air]
    D --> E[Record 25% burn back time]
    E --> F[Evaluate foam thermal stability & sealability]

This test ensures foam quality for firefighting applications per IS 4989 standards.