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Gas Safety

Exam revision materials for Plumbing Level 2&3 and ACS Gas Safety test

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Commissioning

Tightness Test

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Safety Devices and Controls

Air/Gas ratio valves

Appliances Controls

Flame Supervision Devices FSD

Gas Controls

Gas Meter Controls

Safety Cut-off Devices

Spare Part Identification

Pipework

Open-vented System

Ventilation

Gas Appliances

Ventilation Sizing

Unsafe Situations

Dealing with Unsafe Situations

Emergency Notices and Warning Labels

Gas Leak

Regulations

Commissioning

Purging

Tightness Test

Gas Performance

Gas Rate

Heat Input

Gas Supply

Gas Meters

Gas Pipework

Gas Fittings and Pipes

Gas Supply

Materials

New Installation

Pipe Protection

Pipework Sizing

Chimney and Flue

Chimneys

Flue Construction

Flue Inspection and Testing

Flue Terminals

Flue Types

Combustion

Carbon Monoxide Poisoning

Combustion Process

Natural Gas

Portable Combustion Gas Flue Analysers

Boilers

Components and Safety Devices

Regulations

  • Regulations 22 and 23 - Gas Safety (Installation and Use) Regulations 1998
  • IGE/UP/1B Edition 2, Tightness Testing and Purging of Small Natural Gas Installations
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When to carry out?

  • Smell of gas
  • New pipework installation (before it painted or covered)
  • After alteration to, replacement of, or re-use exciting installations
  • Prior to any work on exciting pipework
  • After work on a gas fitting
  • Yearly in rented accommodation
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Pressure Gauges

  • Water Gauge (U-gauge manometer)
    Upperplumbers_manometer

    • indirect reading type (division = 1mbar) and direct reading type (division = 2mbar)
    • Accuracy is 0.5mbar
    • 300mm - size for natural gas (measures up to 30mbar)
    • 1m - size for LPG
    • Water level SHOULD be set at 0
    • Maximum 0.2 mbar perceptible movement
  • Electronic Gauge
    • MIN accuracy - 0.3mbar
    • Must be calibrated and certificated annually
    • Maximum 0.25 mbar perceptible movement
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Soundness Test Procedure

  • Domestic tightness testing if:
    • Meter volume in not greater 16m3/h
    • Meter Operating Pressure is up to 2Bar
    • Maximum 35mm gas installation
  • Let-by Test (ECV is not letting by)
    • rise the pressure to 10mbar
    • isolate the supply
    • maximum 0.5 mbar drop over the next 1 minute
    • National Gas Emergency Call Center shall be notified if ECV is passing the gas when closed
  • Tightness test:
    • Turn off all pilot lights
    • rise the pressure to 20mbar (meter regulator can lock up if higher)
    • left for 1 minute for temperature stabilization
    • no more than 0.5mbar pressure loss within next 2 minutes
    • No pressure drop permitted
      • for installations without appliances
      • for new installations
      • for gas meter
      • for new appliances
Maximum Permissible Pressure Loss
  • Pipe Diameter Ultrasonic meter (up to 6 m3/h)
    E6 or no meter
    Diaphragm meter (up to 6 m3/h)
    U6/G4
    Diaphragm meter (> 6 m3/h and up to 16 m3/h)
    U16/E10
    Up to 28mm 8 mbar 4 mbar 1 mbar
    >28mm and up to 35mm 4.5 mbar 2.5 mbar 1 mbar
  • Pipework only test:
    • rise the pressure to 20mbar (meter regulator can lock up if higher)
    • left for 1 minute for temperature stabilization
    • no more than 0.5mbar pressure loss within next 2 minutes
  • Governor lock-up
    • The governor at the meter is set to give a working pressure of 21mbar (±2mbar)
    • If the pressure goes above 23mbar the valve will be forced into seating (lock up)
    • This would result in the pipe from the ECV to the governor not being tested
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