Specification for Fire Hydrant, Stand Post Type

IS 908: Scope & Key Specifications Summary

• Scope:
  IS 908 specifies requirements for fire hydrants, including stand post types with one or two outlets, ensuring water-tightness and compatibility with related fittings.

• Hydrostatic Test (Clause 5.1):
  Each hydrant must withstand a hydraulic pressure equivalent to 200 meters head without leakage.

• Rounding Off (Clause 0.4):
  Test or calculated values should be rounded per IS 2-1960, retaining the same significant figures as the specified values.

• Key Dimensions (Refer to Figures 1 & 2):

  • Stand post columns, road surface boxes, duckfoot bends, tail pieces, sluice valves (60 mm for single outlet, 100 mm for double outlet)
  • All dimensions are in millimeters.

• Related IS Specifications:

  • Landing valves (internal hydrants)
  • Sluice valves (50–300 mm size)
  • Surface boxes for sluice valves
  • Cast iron fittings and pipes for water/gas/sewage
  • Fire hose delivery couplings, nozzles, spanners
  • Pipe thread dimensions for fastening

Hydrostatic Test Pressure Formula

[ P = \rho g h ]

Where:

• (P) = pressure (Pa)
• (\rho) = density of water (~1000 kg/m³)
• (g) = acceleration due to gravity (9.81 m/s²)
• (h) = head = 200 m

[ P = 1000 \times 9.81 \times 200 = 1.962 \times 10^6 , \text{Pa} = 19.62 , \text{bar} ]

flowchart TD
    A[Fire Hydrant] --> B[Hydrostatic Test]
    B --> C{Pressure}
    C -->|200 m head| D[Water-tightness]
    A --> E[Dimensions]
    E --> F[Stand Post Column]
    E --> G[Sluice Valves]
    E --> H[Road Surface Boxes]

Summary: IS 908 covers fire hydrant design, testing at 200 m head pressure (~19.6

IS 908: General Requirements for Stand Post Fire Hydrants

Key Specifications:

• Hydrostatic Test Pressure: Each hydrant must withstand 200 m head (approx. 2 MPa) without leakage (Clause 5.1).
• Materials & Construction: Must comply with relevant IS standards for cast iron fittings, valves, and couplings (e.g., IS 5200 for landing valves, IS 2 for rounding off).
• Dimensions: Standardized dimensions for components like sluice valves (60 mm for single outlet, 100 mm for double outlet), road surface boxes, duckfoot bends, tail pieces, and stand post columns are specified (all in mm).

Rounding Off Rules:

• Follow IS 2-1960 for rounding test results.
• Retain the same number of significant digits as the specified value.

Typical Component Dimensions (mm):

Hydrostatic Test Formula:

[ P = \rho g h ]

• (P) = Pressure (Pa)
• (\rho) = Density of water (~1000 kg/m³)
• (g) = Acceleration due to gravity (9.81 m/s²)
• (h) = Head (200 m)

flowchart TB
    A[Water Supply] --> B[Underground Pipeline]
    B --> C[Fire Hydrant Stand Post]
    C --> D[Landing Valve]
    C --> E[Sluice Valve]
    C --> F[Hose Coupling Outlet]

This ensures reliable water access for firefighting with tested leak-proof hydrants conforming to IS 908.

IS 908: Materials and Components Key Specifications

• Hydrostatic Test: Each hydrant must withstand 200 m head pressure, proving water tightness (Clause 5.1).

• Landing Valves (Internal Hydrant): Dimensions and flange details per IS: 5200.

• Sluice Valves: Sizes 50 to 300 mm as per the 4th revision of water-works sluice valve specs.

• Cast Iron Fittings: For pressure pipes (water, gas, sewage) per first revision.

• Pipe Threads: Dimensions follow IS: 4218 Part I (basic profile).

• Fire Hose Delivery Components: Couplings, branch pipes, nozzles, and spanners per second revision.

• Typical Dimensions (mm):

  • Stand Post Column & Road Surface Boxes
  • Duckfoot Bend: 100 mm
  • Tail Piece: 80/100 mm
  • Sluice Valve: 60 mm (single outlet), 100 mm (double outlet)

• Marking: Products may carry the Standard Mark per Clause 9.2.1.

Hydrostatic Test Formula

[ P = \rho g h ]

Where:

• (P) = pressure (Pa)
• (\rho) = density of water (~1000 kg/m³)
• (g) = acceleration due to gravity (9.81 m/s²)
• (h) = head (200 m)

Example Calculation:

[ P = 1000 \times 9.81 \times 200 = 1,962,000 \text{ Pa} = 1.96 \text{ MPa} ]

Diagram: Fire Hydrant Stand Post Type (simplified)

graph TB
    A[Stand Post Column]
    B[Opening for Coupling]
    C[Strainer with N holes]
    D[Flange to suit Landing Valve]
    A --> B --> C --> D

For detailed dimensions and specifications, refer to IS 908 figures and related IS codes cited.

IS 908: Workmanship and Finish (Clause 4)

• General Requirements:

  • All parts must have a good finish, free from burrs, blow holes, and sharp edges.
  • Castings must be clean and sound, with no plugging, welding, or repairs of defects allowed.

• Surface Quality:

  • Surfaces should be smooth to ensure proper fit and function.
  • Edges must be deburred to prevent injury and ensure assembly ease.

• Marking (Clause 9.1):

  • Each hydrant must be clearly and permanently marked with:
    • Manufacturer's name or trademark
    • Year of manufacture

• Painting and Coating:

  • Use ready mixed paint as per relevant IS specifications:
    • Bituminous, black, lead-free, acid, alkali, water, and heat resisting.
  • Paint colors and enamel types must comply with IS standards for durability and protection.

Summary Table: Workmanship Checks

flowchart TD
    A[Raw Casting] --> B[Inspection for Defects]
    B -->|No defects| C[Deburring & Finishing]
    B -->|Defects found| D[Reject or Recast]
    C --> E[Marking Manufacturer & Year]
    E --> F[Painting as per IS]
    F --> G[Final Inspection & Dispatch]

Note: Follow IS 2-1960 for rounding off test values related to workmanship.

Hydrostatic Test Requirement (IS 908)

Clause 5.1:

• Each fire hydrant must undergo a hydrostatic test.
• Test pressure: Equivalent to 200 meters head of water.
• Purpose: Ensure the hydrant is perfectly watertight under this pressure.

Key Specifications for Hydrostatic Test:

Additional Relevant Details:

• Material & Finish: All parts must be free from burrs, blow holes, and sharp edges (Clause 4.1).
• Test Scope: Applies to all hydrants, including stand post type with one or two outlets.
• Dimensions & Construction: Refer to figures for stand post columns, sluice valves, and pipe fittings.
• Related IS Codes: IS 5200 (Landing valves), IS 1538 (Sluice valves), IS 277 (Cast iron fittings).

Hydrostatic Pressure Calculation (for reference):

[ P = \rho \times g \times h ]

Where:

• (P) = pressure (Pa)
• (\rho) = density of water (~1000 kg/m³)
• (g) = acceleration due to gravity (9.81 m/s²)
• (h) = height of water column (200 m)

[ P = 1000 \times 9.81 \times 200 = 1,962,000 , \text{Pa} \approx 1.96 , \text{MPa} ]

flowchart TD
    A[Hydrant Assembly] --> B[Apply Water Pressure]
    B --> C{Pressure = 200m Head}
    C --> D[Check for Leakage]
    D -->|No Leakage| E[Pass Test]
    D -->|Leakage| F[Fail Test - Repair]

Summary: Hydrostatic test at 200 m water head (~1.96 MPa) ensures fire hydrants are leak-proof and structurally sound per IS 908.

IS 908 Painting Specifications Summary

• Stand Post Painting (Clause 7.1):

  • Two coats of fire red paint (Shade No. 536, IS:5-1961) on the hydrant stand post.
  • Two coats of canary yellow paint (Shade No. 309, IS:5-1961) on the top of the post column above the outlet.
  • Paint must conform to IS:2932-1964.

• Cast Iron Parts Coating (Clause 6.1):

  • Immediately after casting and cleaning, coat parts by dipping in a bituminous base bath (IS:158-1968).
  • Bath temperature: 143°C to 166°C.
  • Composition adjusted to meet coating properties (see Clauses 6.2 & 6.3).

• Paint Types & Colours:

  • Ready mixed paints: lead-free, acid/alkali/water/heat resistant (second revision).
  • Enamel exterior, Type 2 for undercoating and finishing as required.

• Marking (Clause 9.1):

  • Manufacturer's name/trade-mark and year of manufacture must be clearly and permanently marked.

Key References for Paint Shades & Types

flowchart LR
    A[Cast Iron Parts] -->|Clean & before rusting| B[Bituminous Bath (143-166°C)]
    B --> C[Coated Cast Iron Parts]
    D[Stand Post] -->|2 Coats Fire Red (IS:5-536)| E[Painted Stand Post]
    E -->|Top 2 Coats Canary Yellow (IS:5-309)| F[Finished Hydrant Post]

Note: Always round off

IS 908 - Marking Specifications for Hydrants

• Clause 9.1: Each hydrant must be permanently and clearly marked with:

  • Manufacturer's name or trademark
  • Year of manufacture

• Clause 9.2.1: Optionally, the product may carry the Standard Mark as per BIS regulations.

• Paint Specifications:

  • Use ready mixed paint (bituminous, black, lead-free, acid/alkali/water/heat resistant) for marking.
  • Follow IS paint color standards (second revision).
  • Enamel specifications for exterior undercoating and finishing as required.

• Standard Mark Usage:

  • Governed by the Bureau of Indian Standards Act, 1986.
  • Licensing conditions available from BIS offices nationwide.

Summary Table for Marking Information

Contact for BIS Licensing & Standards

• Headquarters: Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi 110002
• Email: bis@vsnl.com
• Website: bis.org.in

This ensures traceability and quality assurance per IS 908 requirements.

IS 908: Criteria for Acceptance - Key Points

1. General Acceptance Criteria (Clause 4.1):

   • All parts must have a good finish free from burrs, blow holes, and sharp edges.
   • Castings must be clean and sound without plugging, welding, or repairs.

2. Hydrostatic Test Requirement (Clause 5.1):

   • Each hydrant must be tested for water tightness under a hydraulic pressure equivalent to 200 meters head.
   • The hydrant should prove perfectly water tight.

3. Rounding Off Values (Clause 0.4):

   • Final values from tests or analysis must be rounded off as per IS 2-1960.
   • The number of significant figures retained should match the specified value in the standard.

4. Painting Specifications (Clause 7.1):

   • Stand post painted with two coats of fire red paint (IS 5-1961 Shade No. 536).
   • Top of post above outlet painted with two coats of canary yellow (IS 5-1961 Shade No. 309).
   • Paint to conform to IS 2932-1964.

Hydrostatic Test Pressure Calculation

[ P = \rho g h ]

Where:

• (P) = pressure (Pa)
• (\rho) = density of water (~1000 kg/m³)
• (g) = acceleration due to gravity (9.81 m/s²)
• (h) = head (200 m)

[ P = 1000 \times 9.81 \times 200 = 1,962,000 \text{ Pa} = 19.62 \text{ bar} ]

Summary Table

IS 908 - Testing and Inspection: Key Points

1. Hydrostatic Test (Clause 5.1):

• Each hydrant must withstand a hydrostatic pressure equivalent to 200 meters head of water.
• It should be perfectly watertight under this pressure.

2. Rounding Off Test Results (Clause 0.4):

• Final test values must be rounded according to IS 2-1960.
• The number of significant digits retained should match the specified value's precision.

3. Visual and Physical Inspection (Clause 4.1):

• All parts must be free from burrs, blowholes, sharp edges.
• Castings must be clean, sound, and free from repairs like plugging or welding.

Hydrostatic Pressure Formula

To convert pressure head to pressure:
[ P = \rho \times g \times h ] Where:

• (P) = Pressure (Pa)
• (\rho) = Density of water (~1000 kg/m³)
• (g) = 9.81 m/s²
• (h) = Head (200 m)

[ P = 1000 \times 9.81 \times 200 = 1,962,000 \text{ Pa} = 1.96 \text{ MPa} ]

Summary Table

flowchart TD
    A[Start: Hydrant Fabrication] --> B[Visual Inspection]
    B --> C{Defects?}
    C -- Yes --> D[Reject/Repair]
    C -- No --> E[Hydrostatic Test @ 200m head]
    E --> F{Leakage?}
    F -- Yes --> D
    F -- No --> G[Pass & Final Rounding of Test Results]

This ensures compliance with IS 908 for hydrant testing and inspection.