AS 3814-2009

1 - AS 3814-2009 INDUSTRIAL AND COMMERCIAL GAS-FIRED APPLIANCES
4 - PREFACE
6 - CONTENTS
8 - SECTION 1 SCOPE, APPLICATION AND DEFINITIONS
8 - 1.1 SCOPE
8 - 1.1.1 General
8 - 1.1.2 Exclusions from Standard
8 - 1.2 APPLICATION
8 - 1.2.1 General
9 - 1.2.2 Appliance installation
9 - 1.2.3 New materials and methods
9 - 1.2.4 Unusual installations
9 - 1.2.5 Modification or relocation of an appliance
9 - 1.3 REFERENCED DOCUMENTS
10 - 1.4 DEFINITIONS
10 - 1.4.1 Accessible
10 - 1.4.2 Air curtain
10 - 1.4.3 Air-gas mixing machine
10 - 1.4.4 Appliance
10 - 1.4.4.1 Type A appliance
11 - 1.4.4.2 Type B appliance
11 - 1.4.5 Approved
11 - 1.4.6 Atmospheric burner
11 - 1.4.7 Authorized installer
11 - 1.4.8 Auto-ignition temperature (AIT)
11 - 1.4.9 Automatic burner
11 - 1.4.10 Automatic ignition
11 - 1.4.11 Bleed line
11 - 1.4.12 Burner
11 - 1.4.12.1 Atmospheric burner
11 - 1.4.12.2 Automatic burner
11 - 1.4.12.3 Forced draught burner
11 - 1.4.12.4 Induced draught burner
11 - 1.4.12.5 Multi-fuel alternative burner
12 - 1.4.12.6 Multi-fuel burner
12 - 1.4.12.7 Multi-fuel simultaneous burner
12 - 1.4.12.8 Part automatic burner
12 - 1.4.13 Burner off cycle
12 - 1.4.14 Burner unit
12 - 1.4.15 Certified/Certification
12 - 1.4.16 Certifying body
12 - 1.4.17 Combination gas control
12 - 1.4.18 Combustion products
12 - 1.4.19 Common flue
12 - 1.4.20 Critical time
12 - 1.4.21 Cross lighting
12 - 1.4.22 Damper
13 - 1.4.23 Direct-fired air heater
13 - 1.4.24 Direct-fired oven
13 - 1.4.25 Double block and vent
13 - 1.4.26 Draught diverter
13 - 1.4.27 Electronic flame safeguard
13 - 1.4.28 Excess air
13 - 1.4.29 Fail-safe
13 - 1.4.30 Flame abnormality
13 - 1.4.31 Flame detector
13 - 1.4.32 Flame establishment period
13 - 1.4.33 Flame failure response time
13 - 1.4.34 Flame lift
13 - 1.4.35 Flame proving period
13 - 1.4.36 Flame safeguard
14 - 1.4.37 Flame safeguard system
14 - 1.4.38 Flue
14 - 1.4.38.1 Common flue
14 - 1.4.38.2 Natural draught flue
14 - 1.4.38.3 Open flue
14 - 1.4.38.4 Secondary flue
14 - 1.4.38.5 Slip joint
14 - 1.4.39 Flue gases
14 - 1.4.40 Flue system
14 - 1.4.41 Flue terminal
14 - 1.4.42 Flued appliance
14 - 1.4.43 Flueless appliance
14 - 1.4.44 Forced draught burner
14 - 1.4.45 Forced or induced draught combustion system
14 - 1.4.46 Gas
15 - 1.4.46.1 Natural gas (NG)
15 - 1.4.46.2 Simulated natural gas (SNG)
15 - 1.4.46.3 Town gas (TG)
15 - 1.4.46.4 Tempered liquefied petroleum gas (TLP)
15 - 1.4.46.5 Liquefied petroleum gas (LP gas)
15 - 1.4.47 Gas/air ratio control
15 - 1.4.48 Gas consumption
15 - 1.4.49 Gasfitting work
15 - 1.4.50 Gas pressure regulator
15 - 1.4.51 Gas tight
15 - 1.4.52 Hazardous conditions
15 - 1.4.53 High gas pressure detector
15 - 1.4.54 Hose
15 - 1.4.55 Hose assembly
15 - 1.4.56 Hot water boiler
15 - 1.4.57 Ignition temperature
16 - 1.4.58 In service
16 - 1.4.59 Indoor flueless appliance
16 - 1.4.60 Induced draught burner
16 - 1.4.61 Injector
16 - 1.4.62 Interlock
16 - 1.4.63 Intermittent pilot
16 - 1.4.64 Interrupted pilot
16 - 1.4.65 Leakage detection system
16 - 1.4.66 Light back
16 - 1.4.67 Limit device
16 - 1.4.68 Lockout
16 - 1.4.69 Lower explosive limit (LEL)
16 - 1.4.70 Low-gas-pressure detector
16 - 1.4.71 Manual ignition
17 - 1.4.72 Mixing blower
17 - 1.4.73 Mixing tube
17 - 1.4.74 Modification
17 - 1.4.75 Multi-fuel alternative burner
17 - 1.4.76 Multi-fuel burner
17 - 1.4.77 Multi-fuel simultaneous burner
17 - 1.4.78 Natural draught
17 - 1.4.79 Natural draught burner
17 - 1.4.80 Natural draught flue
17 - 1.4.81 No-flow
17 - 1.4.82 Nominal gas consumption
17 - 1.4.83 Non-return valve
17 - 1.4.84 Open flued appliance
17 - 1.4.85 Operating pressure
17 - 1.4.86 Over-pressure protection system
18 - 1.4.87 Over-temperature cut-out device
18 - 1.4.88 Over-temperature limiting device
18 - 1.4.89 Part automatic burner
18 - 1.4.90 Permanent pilot
18 - 1.4.91 Pilot
18 - 1.4.92 Position indicator switch
18 - 1.4.93 Closed position indicator switch
18 - 1.4.94 Open position indicator switch
18 - 1.4.95 Position-proving system
18 - 1.4.96 Process after-burner
18 - 1.4.97 Programmable electronic system (PES)
18 - 1.4.98 Programming flame safeguard
18 - 1.4.99 Proof-of-closure switch
18 - 1.4.100 Protected pilot
18 - 1.4.101 Purge (or purging)
19 - 1.4.102 Purge volume
19 - 1.4.103 Rated working pressure
19 - 1.4.104 Regulator
19 - 1.4.105 Relief device
19 - 1.4.106 Safe start check
19 - 1.4.107 Safety shutdown
19 - 1.4.108 Safety shut off system
19 - 1.4.109 Safety shut off system, double block and vent
19 - 1.4.110 Safety shut off valve
19 - 1.4.111 Set pressure
19 - 1.4.112 Start gas
19 - 1.4.113 Steam boiler
19 - 1.4.114 Stoichiometric combustion
20 - 1.4.115 Supervised burner
20 - 1.4.116 Supervised pilot
20 - 1.4.117 Technical regulator
20 - 1.4.118 Temperature limit device
20 - 1.4.119 Test firing valve
20 - 1.4.120 Thermostat
20 - 1.4.121 Valve
20 - 1.4.122 Valve train
20 - 1.4.123 Vent line
20 - 1.4.124 Vent valve, double block and vent safety shut off system
20 - 1.4.125 Water heater
21 - SECTION 2 REQUIREMENTS FOR DESIGN AND CONSTRUCTION
21 - 2.1 GENERAL REQUIREMENTS
21 - 2.1.1 Appliance design
21 - 2.1.2 Suitability for location
21 - 2.1.3 Controls and indicating devices
21 - 2.1.4 Design of adjustable devices
21 - 2.1.5 Appliance to be well constructed
21 - 2.1.6 Appliance parts to be secure against accidental displacement
21 - 2.1.7 Appliance parts to be secure for satisfactory operation
22 - 2.1.8 Appliance to be free of sharp edges
22 - 2.1.9 Appliance supports to be of adequate strength
22 - 2.1.10 Provision to be made for sampling flue gases
22 - 2.2 CONTROLS, BURNER AND SAFETY DEVICE ACCESS
22 - 2.3 FLAME VISIBILITY
22 - 2.3.1 Flame to be visible to maintenance personnel
22 - 2.3.2 Visual indication of flame to operator
22 - 2.4 TEMPERATURES OF SURFACES AND COMPONENTS
23 - 2.5 RESTRICTION ON ELECTRICAL CONNECTIONS
23 - 2.5.1 Ease of connection
23 - 2.5.2 Limit on cross-connection
23 - 2.6 ACCESSIBILITY OF MANUAL CONTROLS
23 - 2.7 MATERIALS
23 - 2.7.1 Materials to be adequate for their intended application
23 - 2.7.2 Restriction on use of zinc-base die-castings
23 - 2.7.3 Materials to be suitable for gas
24 - 2.8 GAS PIPEWORK AND VALVE TRAINS
24 - 2.8.1 Gas pipework and valve trains
24 - 2.8.2 Enclosure for a valve train
25 - 2.8.3 Pressure rating of valve train components
25 - 2.8.3.1 Upstream of and including appliance gas pressure regulator
25 - 2.8.3.2 Downstream of appliance gas pressure regulator
25 - 2.8.4 Requirements where pressurized air, oxygen or a standby gas is to be used
25 - 2.8.5 Multi-position manual control valves
25 - 2.8.6 Design of valve handles, dials and pointers
25 - 2.8.7 Appliance isolating valve
25 - 2.8.7.1 Appliance isolating valve to be fitted
25 - 2.8.7.2 Requirements for appliance isolating valve
26 - 2.8.7.3 Location of appliance isolating valve
26 - 2.8.7.4 Identification of appliance isolating valve
26 - 2.8.7.5 Connection of appliance isolating valve
26 - 2.8.8 Main Burner Isolation
26 - 2.8.8.1 Main burner isolation valve
26 - 2.8.8.2 Main burner isolation for commissioning
27 - 2.8.9 Restriction on test firing valve
27 - 2.8.10 Pilot burner isolating valve
27 - 2.9 GAS PRESSURE REGULATION
27 - 2.9.1 Gas pressure regulator to be fitted
27 - 2.9.2 Requirements for a gas pressure regulator
28 - 2.9.4 Position of gas pressure regulator
28 - 2.9.5 Venting of gas pressure regulator
28 - 2.10 GAS OVER-PRESSURE PROTECTION
28 - 2.10.1 Requirement where over-pressure protection shuts off the gas supply
28 - 2.10.2 Where over-pressure protection system is to be fitted
28 - 2.10.3 Setting of over-pressure protection system
29 - 2.10.4 Location of over-pressure protection system sensing point
29 - 2.11 GAS LOW-PRESSURE PROTECTION
29 - 2.11.1 Low-gas-pressure detector to be fitted
29 - 2.11.2 Requirements of low-gas-pressure detector
29 - 2.12 GAS PRESSURE TEST POINTS
29 - 2.12.1 Location of pressure test points
29 - 2.12.2 Maximum orifice size of a pressure test point
29 - 2.12.3 Sealing of a pressure test point
30 - 2.13 GAS FILTER
30 - 2.13.1 Filter to be fitted
30 - 2.13.2 Requirements and location of filter
30 - 2.14 SAFETY SHUT OFF SYSTEMS
30 - 2.14.1 Safety shut off valve and vent valve
30 - 2.14.2 Function of safety shut off system
30 - 2.14.3 Safety shut off valve system requirements for main and start gas supplies
30 - 2.14.3.1 General
31 - 2.14.3.2 Concession for atmospheric burner not exceeding 500MJ/h
31 - 2.14.3.3 Concession for atmospheric burner not exceeding 1GJ/h
31 - 2.14.3.4 Concession for forced or induced draught burner up to 200MJ/h
31 - 2.14.3.5 Concession for forced or induced draught burner up to 1GJ/h
31 - 2.14.3.6 Concession for a main burner up to 1GJ/h igniting at low rate
32 - 2.14.3.7 Concession for a burner using a separate start gas line
32 - 2.14.3.8 Provision for start gas to be taken from between safety shut off valves for a main burner directly ignited at a low rate
33 - 2.14.4 Energizing of automatic safety shut off valves
33 - 2.14.5 Ignition of main burner by separate pilot
33 - 2.14.6 Requirements for a safety shut off valve and vent valve
33 - 2.14.6.1 Rated working pressure
33 - 2.14.6.2 Orientation
34 - 2.14.6.3 Size of vent valve for a double block and vent safety shut off system
34 - 2.14.6.4 Size of vent valve for a leakage detection system
34 - 2.14.6.5 Arrangement for manual reset vent valve
34 - 2.14.7 Safety shut off system not to be bypassed
34 - 2.14.8 Vent line requirement
34 - 2.14.9 Requirements for a position-proving system
34 - 2.14.9.1 Safety shut off valve
34 - 2.14.9.2 Vent valve
35 - 2.14.9.3 Position-proving system to be interlocked to prevent burner start-up
35 - 2.14.9.4 Alarm interlock
35 - 2.14.10 Requirements for a leakage detection system
35 - 2.14.10.1 Compliance with Standard
35 - 2.14.10.2 Leakage detection system to be interlocked to cause lockout
36 - 2.14.10.3 Commencement of leakage detection test
36 - 2.14.10.4 Alarm interlock
36 - 2.14.10.5 Maximum allowable leakage rate
36 - 2.14.10.6 Leakage detection system that uses gas at line pressure
37 - 2.14.11 Function of interlocks
37 - 2.14.12 Requirements of safety shut off system actuators
37 - 2.14.12.1 Individual actuators to be fitted
37 - 2.14.12.2 Single three-way valve permitted
37 - 2.14.12.3 Use of rigidly coupled actuators
37 - 2.15 COMBUSTION AIR SUPPLY-GENERAL REQUIREMENTS
37 - 2.15.1 Combustion air supply equipment to be correctly sized
38 - 2.15.2 Combustion air quality
38 - 2.15.3 Air openings to be of adequate size
38 - 2.15.4 Air openings not to be obstructed
38 - 2.16 COMBUSTION AIR FOR ATMOSPHERIC BURNERS
38 - 2.16.1 Primary aeration controls to be corrosion-resistant
38 - 2.16.2 Effect of foreign matter on primary aeration controls to be minimal
38 - 2.17 FORCED AND INDUCED DRAUGHT BURNERS
38 - 2.17.1 Draught characteristics to be specified by burner manufacturer
38 - 2.17.2 Proving air flow
38 - 2.17.3 Self-check of air flow proving device
38 - 2.17.3.1 Self-check to be carried out
38 - 2.17.3.2 Failure of air flow proving device during self-check
39 - 2.17.4 Safety shutdown to occur if air flow fails
39 - 2.17.5 Air-gas mixtures
39 - 2.17.5.1 Air-gas mixing machines and mixing blowers
39 - 2.17.5.2 Maximum temperature of mixtures
39 - 2.18 DAMPERS
39 - 2.18.1 Requirements for a fixed or adjustable damper
39 - 2.18.2 Requirements for an automatic damper control system
39 - 2.18.2.1 Automatic damper to maintain satisfactory combustion
40 - 2.18.2.2 Failure of damper mechanism
40 - 2.18.2.3 Manual damper control
40 - 2.19 APPLIANCE PRE-PURGING
40 - 2.19.1 General requirements
40 - 2.19.1.1 Function of pre-purge
40 - 2.19.1.2 Appliance or process to be pre-purged
40 - 2.19.1.3 Pre-purging using an inert medium
40 - 2.19.1.4 Supply of inert purging medium to be proved
40 - 2.19.2 Pre-purging by mechanical means
40 - 2.19.2.1 Mechanical pre-purging required under certain conditions
41 - 2.19.2.2 Conduct of mechanical pre-purge
41 - 2.19.3 Pre-purging using natural draught
41 - 2.19.3.1 Requirements for an appliance using natural draught
41 - 2.19.3.2 Pre-purge period using natural draught
41 - 2.19.3.3 Pre-purge period included in operating instructions
42 - 2.19.3.4 Pre-purge where appliance doors are opened
42 - 2.19.4 Pre-purge timer
42 - 2.19.5 Pre-purge interlocks
42 - 2.19.5.1 Purge flow proving device to be fitted
42 - 2.19.5.2 Self-check of purge flow proving device
42 - 2.19.5.3 Purging to cease if purge flow fails
42 - 2.19.5.4 Pre-purge to reset when purge flow is re-established
42 - 2.19.5.5 Proof of operation of zone circulation fans in appliances
43 - 2.20 PROCESS CONTROLS
43 - 2.20.1 Requirements where appliance safety depends on process
43 - 2.20.2 Process limit device to cause lockout
43 - 2.20.3 Requirements where appliance safety and operation depend on flow
43 - 2.20.4 Provision of over temperature protection on recirculation fans
43 - 2.21 IGNITION SYSTEMS
43 - 2.21.1 Ignition to be safe, reliable and smooth
43 - 2.21.2 Manual ignition systems
43 - 2.21.2.1 Requirements for a manually-inserted gas torch
43 - 2.21.2.2 Point of ignition to be accessible
43 - 2.21.2.3 Explosion relief to be provided for a manually-ignited burner
44 - 2.22 PILOT BURNERS
44 - 2.22.1 Requirements for a pilot burner with a single main burner
44 - 2.22.2 Requirements for supervised pilot burners with multiple main burners
44 - 2.22.3 Flames to travel freely to all ports of a multi-port pilot
44 - 2.22.4 Bleed lines not to affect ignition of main burner
44 - 2.22.5 Protection from blockage
44 - 2.23 MAIN BURNERS
44 - 2.23.1 Ignition to be in combustion chamber
44 - 2.23.2 Main burners subdivided into zones or sections
44 - 2.23.3 Requirements for a burner that can be retracted or swivelled
45 - 2.23.4 Requirements for cross-ignition
45 - 2.23.5 Protection from blockage
45 - 2.24 FLAME SAFEGUARD SYSTEMS
45 - 2.24.1 Requirements for a flame safeguard system
45 - 2.24.2 Flame safeguard system to be fitted
45 - 2.24.3 Flame safeguard to comply with classification
45 - 2.24.4 Maximum hold-time for a thermoelectric flame safeguard
46 - 2.24.5 Maximum shut off time following flame failure
47 - 2.24.6 Requirements for a flame detector
47 - 2.24.7 Flame simulation to be prevented
47 - 2.24.8 Detector not to detect other flame
47 - 2.24.9 Requirements for a pilot used on atmospheric burner(s) exceeding 1 GJ/h (275 kW), or forced or induced draught burner(s)
47 - 2.24.10 Detectors to supervise separate flames
47 - 2.24.11 Requirements for two flame detectors used with one flame safeguard device or system
47 - 2.24.12 Detector to ensure cross lighting is complete
48 - 2.24.13 Requirements for flame safeguards incorporating hot surface igniters
48 - 2.25 BLEED LINES
48 - 2.25.1 General requirements for a bleed line termination
48 - 2.25.2 Terminating bleed lines in a combustion chamber
48 - 2.25.2.1 Combustion chamber to have a supervised burner
48 - 2.25.2.2 Bleed line requirements
48 - 2.25.2.3 Bleed line termination to be protected against blockage
48 - 2.26 APPLIANCE/BURNER CONTROL CIRCUITS
48 - 2.26.1 Requirements of control circuits
49 - 2.26.2 Gas-actuated controls
49 - 2.26.3 Requirements for a programmable electronic system (PES)
50 - 2.27 GAS/AIR RATIO CONTROL
50 - 2.27.1 General requirements
52 - 2.27.2 Interference with interlocks
52 - 2.27.3 Variation in control settings and control response
52 - 2.27.4 Preheated combustion air control
52 - 2.27.5 Requirements for independent gas and air control elements
52 - 2.27.6 Special requirements for PES based gas/air ratio control system
52 - 2.27.7 Additional requirements for pneumatically controlled gas/air ratio
53 - 2.27.8 Gas/air ratio controls incorporating variable speed drive systems
53 - 2.27.9 Use of oxygen sensing probes
54 - SECTION 3 OPERATION
54 - 3.1 APPLIANCE OPERATION DETAILS
54 - 3.2 IGNITION
54 - 3.2.1 Starting sequence interlocks before starting burner ignition source
54 - 3.2.2 Ignition sequence
54 - 3.2.2.1 Commencement of ignition
54 - 3.2.2.2 Completion of ignition
54 - 3.2.2.3 Start gas flame establishment period
55 - 3.2.3 Start gas rate
55 - 3.2.3.1 Start gas rate not to exceed determined values
56 - 3.3 MAIN BURNERS
56 - 3.3.1 Start flame proving period
56 - 3.3.2 Main flame establishment period
56 - 3.3.3 Main burner supervision
56 - 3.3.3.1 Interrupted pilot
56 - 3.3.3.2 Intermittent or permanent pilot with a forced or induced draught burner or atmospheric burner exceeding 1GJ/h (275kW)
57 - 3.3.4 Main burner to start at reduced rate
57 - 3.4 INTERLOCKS AND LIMIT DEVICES
57 - 3.4.1 Interlocks and limit devices not to be rendered ineffective
57 - 3.4.1.1 Where an interlock is to be fitted
57 - 3.4.1.2 Interlock to be tested
57 - 3.4.1.3 Requirements for an interlock
58 - 3.4.2 Limit devices
58 - 3.4.2.1 Limit device to be fitted
58 - 3.4.2.2 Limit device not to be an operating control
58 - 3.4.2.3 Requirements for a limit device
58 - 3.5 OPERATION SEQUENCES
58 - 3.5.1 Ignition sequence after power interruption
58 - 3.5.2 Programmed sequence for automatic or part automatic burner
59 - 3.5.3 Appliance to be left in safe condition
59 - 3.5.4 Requirement for lockout on flame failure
59 - 3.5.5 Reignition attempt on flame failure
59 - 3.5.5.1 Requirements for forced or induced draught burners
59 - 3.5.5.2 Requirements for atmospheric burners
59 - 3.6 COMBUSTION CONDITIONS
59 - 3.6.1 Burners to maintain satisfactory combustion conditions
60 - 3.6.2 Leakage of combustion products to be prevented
60 - 3.7 COMMISSIONING
60 - 3.7.1 Commissioning checks to be carried out
61 - SECTION 4 MARKINGS AND INSTRUCTIONS
61 - 4.1 MARKINGS
61 - 4.1.1 Markings to be displayed
61 - 4.1.2 Marking of controls, dials and gauges
61 - 4.1.3 Controls with non-standard operation
61 - 4.2 INSTRUCTIONS
61 - 4.2.1 Written instructions to be provided
62 - 4.2.2 Instructions for operation
62 - 4.2.3 Limits of safe operation to be specified
63 - SECTION 5 SPECIAL APPLICATION REQUIREMENTS
63 - 5.1 GENE
63 - 5.2 HIGH INPUT GAS-FIRED APPLIANCES
63 - 5.2.1 General
63 - 5.2.2 Start-up where multiple main burners are fitted
63 - 5.2.3 Manual ignition where multiple main burners are fitted
63 - 5.2.4 Automatic ignition where multiple main burners are fitted
63 - 5.2.5 Burner control
63 - 5.2.6 Flame safeguards
64 - 5.3 AIR-GAS MIXING MACHINES AND MIXING BLOWERS
64 - 5.3.1 General
64 - 5.3.2 Materials
64 - 5.3.3 Strength of pipe and fittings
64 - 5.3.4 Safety shut off system to be fitted
64 - 5.3.5 Safety shut off system to cause lockout
64 - 5.3.6 Air-gas ratio
64 - 5.3.6.1 Locking provision for air-gas ratio from a mixing machine
64 - 5.3.6.2 Limiting provision for air-gas ratio from a mixing machine
64 - 5.3.6.3 Air-gas ratio from a mixing blower
64 - 5.3.7 Mixing blower outlets
65 - 5.3.8 Flashback requirements for air-gas mixing machines
65 - 5.3.9 Rupture of blow-out disc
65 - 5.3.10 Flame arrestor between air-gas mixing machine and burner
65 - 5.3.11 Flame arrestor at mixing machine
65 - 5.3.12 Flame arrestors
65 - 5.3.13 Air-gas mixing machines - requirement for non-return valve
66 - 5.4 SPECIAL ATMOSPHERES AND ATMOSPHERE GENERATORS
66 - 5.4.1 General
66 - 5.4.2 Piping for special atmospheres
66 - 5.4.3 Storage of special atmosphere
66 - 5.4.4 Storage container for compressed special atmosphere
66 - 5.4.5 Venting and disposal of special atmospheres
66 - 5.4.6 Discharge using a vent line
66 - 5.4.7 Start-up of an atmosphere generator
67 - 5.4.8 Ignition
67 - 5.4.9 Requirement where the air-gas ratio is variable
67 - 5.4.10 Requirements where the air-gas ratio is fixed
67 - 5.4.11 Automatic relief device
67 - 5.4.12 Flame arrestor
67 - 5.4.13 Water-cooled equipment
67 - 5.4.14 Exothermic atmosphere generators
67 - 5.4.14.1 Flame safeguard requirement
68 - 5.4.14.2 Flame safeguard bypass
68 - 5.4.14.3 Pressure detectors to be fitted
68 - 5.4.14.4 Pressure detectors to be interlocked
68 - 5.4.14.5 Interlocking combustible atmosphere flow
68 - 5.4.14.6 Purging
68 - 5.4.14.7 Air-gas ratio control
68 - 5.4.15 Endothermic atmosphere generators
68 - 5.4.15.1 Safety shut off valves to be fitted
68 - 5.4.15.2 Air shut off device
68 - 5.4.15.3 Pressure detectors
68 - 5.5 PROCESS AFTER-BURNERS
68 - 5.5.1 General
69 - 5.5.2 Control of process products
69 - 5.5.2.1 Requirement for interlocks
69 - 5.5.2.2 Process products-percentage of LEL
69 - 5.5.3 Combustion air supply
69 - 5.5.4 Shutting down of process afterburner
69 - 5.5.5 Pre-purge
70 - 5.6 STEAM AND HOT WATER BOILERS
70 - 5.7 DIRECT-FIRED AIR HEATERS AND CURTAINS
70 - 5.7.1 General
70 - 5.7.2 Heater air supply
70 - 5.7.3 Air flow sensing device
70 - 5.7.4 Pre-purge
70 - 5.7.5 Temperature limit device
70 - 5.7.6 Start gas rate
70 - 5.7.7 Combustion
70 - 5.7.7.1 Limits for combustion products
71 - 5.7.7.2 Samples of heated air to be taken
71 - 5.7.7.3 Limitation on air temperature
71 - 5.7.7.4 Combustion at minimum air flow
71 - 5.7.8 Markings
71 - 5.7.8.1 Marking plate to be fitted
71 - 5.7.8.2 Restriction on installation
72 - 5.8 STATIONARY GAS ENGINES AND TURBINES
72 - 5.8.1 General
72 - 5.8.2 Requirement for safety shut off valve system
72 - 5.8.2.1 Safety shut off system to be fitted
72 - 5.8.2.2 Safety shut off valves and vent valves
73 - 5.8.2.3 Emergency isolation and vent valves
73 - 5.8.2.4 Activation of the safety shut off system to shut off gas supply
73 - 5.8.3 Turbine purging
74 - 5.8.4 Gas supply flexible connection
74 - 5.8.5 Exhaust system to be fitted
74 - 5.8.6 Flexible connection to be fitted to exhaust line
74 - 5.8.7 Requirements of an exhaust system
74 - 5.8.8 Exhaust terminal location
74 - 5.8.9 Ventilation
74 - 5.8.10 Requirements for Ignition
75 - 5.8.11 Extinction safety time
75 - 5.8.12 Indirect flame monitoring
75 - 5.9 INCINERATORS AND CREMATORS
75 - 5.9.1 General
75 - 5.9.2 Primary burner interlock
75 - 5.9.3 Combustion air
76 - 5.9.4 Pre-purge
76 - 5.9.5 Flues
76 - 5.9.5.1 Flues not to be interconnected
76 - 5.9.5.2 Limiting updraught
76 - 5.10 ROTARY PROCESS EQUIPMENT AND OVENS-DIRECT-FIRED
76 - 5.10.1 General
76 - 5.10.2 Purging
76 - 5.10.3 Provision of air
77 - 5.10.4 Explosion relief
77 - 5.10.5 Temperature limit device
77 - 5.10.6 Access for cleaning
77 - 5.10.7 Processes with solvents or combustible dust
77 - 5.10.7.1 Provision of dilution air
77 - 5.10.7.2 Recirculation air fans
77 - 5.10.7.3 Monitoring of solvent LEL
78 - 5.11 SMOKE OVENS-DIRECT-FIRED
78 - 5.11.1 Lighting torch
78 - 5.11.2 Combustion air
78 - 5.11.2.1 Combustion air to be provided from outside of oven
78 - 5.11.2.2 Restrictions on the use of ducting
78 - 5.11.2.3 Smoke not to interfere with combustion
78 - 5.11.3 Explosion relief requirements
78 - 5.11.4 Loading doors
78 - 5.11.5 Sawdust trays
78 - 5.11.6 Flue
78 - 5.11.6.1 Minimum requirements for natural draught flue
78 - 5.11.6.2 Flue damper
79 - 5.12 WATER HEATERS
79 - 5.12.1 General
79 - 5.12.2 Thermostat
79 - 5.12.3 Over-temperature control
79 - 5.12.3.1 Over-temperature cut-out device to be fitted
79 - 5.12.3.2 Over-temperature cut-out to initiate lockout
79 - 5.12.4 Unvented water heaters
79 - 5.12.4.1 Relief valve to be fitted
79 - 5.12.4.2 Location of relief valves
79 - 5.12.4.3 Heaters containing 1L of water or less
79 - 5.12.5 Provision for draining
80 - 5.13 MULTI-FUEL FIRING SYSTEMS
80 - 5.13.1 Alternative multi-fuel systems
80 - 5.13.1.1 Isolation of alternative fuel supply
80 - 5.13.1.2 Alternative fuel system to be interlocked
80 - 5.13.1.3 Fuel lines to be sealed on disconnection
80 - 5.13.2 Multi-fuel simultaneous firing systems
80 - 5.13.2.1 Maximum operating input
80 - 5.13.2.2 Combustion air requirement
81 - APPENDIX A - TYPICAL INFORMATION AND TECHNICAL DATA
85 - APPENDIX B - TYPICAL PROCEDURE FOR THE APPROVAL OF INDUSTRIAL AND COMMERCIAL APPLIANCES
86 - APPENDIX C - TYPICAL VALVE TRAIN ARRANGEMENTS
92 - APPENDIX D - FLAME SAFEGUARD SELECTION
94 - APPENDIX E - PRO-FORMA LETTER TO THE GAS TECHNICAL REGULATOR FROM A CONTRACTOR/COMPANY CERTIFYING THE TESTS CONDUCTED ON THE PES
95 - APPENDIX F - GAS/AIR RATIO CONTROL PROGRAMMABLE ELECTRONIC SYSTEMS
95 - F1 INTRODUCTION
95 - F2 DEFINITION OF GAS/AIR RATIO CONTROL PROGRAMMABLE ELECTRONIC SYSTEMS
95 - F3 PARAMETERISABLE SYSTEMS THAT DO NOT REQUIRE A LOW OXYGEN LIMIT DEVICE
96 - F4 PARAMETERISABLE SYSTEMS THAT REQUIRE A LOW OXYGEN LIMIT
96 - F5 PES GAS/AIR RATIO CONTROL SYSTEMS
97 - F6 ADDITIONAL REQUIREMENTS FOR BURNER MANAGEMENT SYSTEMS FITTED WITH LOW OXYGEN LIMIT DEVICE
97 - F6.1 The oxygen probe that could act as an ignition source
97 - F6.2 With an oxygen probe that does not act as an ignition source
98 - APPENDIX G - MAINTENANCE AND CHECKS OF SAFETY DEVICES
98 - G1 INTRODUCTION
98 - G2 REGULAR TESTING
98 - G3 PERSONNEL AND ORGANIZATION
98 - G4 GENERAL OUTLINE OF PROCEDURES
99 - G5 TESTING SCHEDULES
103 - APPENDIX H - TYPICAL OPERATING SEQUENCE FOR AN AUTOMATIC FORCED OR INDUCED DRAUGHT BURNER WITH INTERRUPTED PILOT
106 - APPENDIX I - TYPICAL COMMISSIONING PROCEDURE
106 - I1 SCOPE
106 - I2 STAGE 1 PRELIMINARY INSPECTION
106 - I3 STAGE 2 ACTIVATION-RUN WITHOUT FUEL
107 - I4 STAGE 3 ACTIVATION-RUN WITH FUEL
107 - I5 STAGE 4 OPERATION
108 - I6 STAGE 5 COMPLETION
109 - APPENDIX J - TYPICAL FIELD CHECK LIST

Specifies the uniform minimum requirements for the design, construction and safe operation of TypeB appliances that are intended for use with town gas, natural gas, simulated natural gas, liquefied petroleum gas and tempered liquefied petroleum gas or any combination of these gases either together or with other fuels.

GeneralThis Standard provides minimum requirements for the design, construction and safe operation of Type B appliances that use town gas, natural gas, simulated natural gas, liquefied petroleum gas, tempered liquefied petroleum gas or any combination of these gases either together or with other fuels.Construction requirements given relate only to matters affecting gas-firing or to any interconnection between the gas-firing system and the safety requirements of the appliance.NOTE: Additional information regarding safety principles for industrial appliances is given in AS 1375.The Standard does not cover all the requirements for the safety of the process carried out in the appliance. Other statutory and regulatory requirements may be applicable to the appliances and/or installations that fall within the scope of this Standard. It is the installer/manufacturer’s responsibility to ensure that appliances and/or installations comply with these requirements.Installation requirements for appliances covered by this Standard are detailed in AS 5601.Exclusions from StandardThe following appliances are excluded from this Standard:(a) Manually operated bunsen type burners.(b) Simple atmospheric burners that are not fitted into a combustion chamber and burn in an open ventilated space under the control of an operator.(c) Engines other than stationary engines.

Originated as AG 501-1984 Previous edition 2002.
Republished and designated AS 3814-2005.
Second edition 2009.
Reissued incorporating Amendment No. 1 (June 2010).