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53 Cards in this Set
- Front
- Back
- 3rd side (hint)
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This is added to Natural Gas to give it a distinguishable odour: |
Butyl Mercaptan |
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True or False? Butyl Mercaptan is added to propane to give it a distinguishable odour. |
False: Ethyl Mercaptan is added to propane |
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Methane accounts for ___________% of Natural Gas, followed by ___________% ethane. |
>90% (89.68) >5% (4.68) |
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What is the chemical formula for propane? |
C3H8 |
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What is another name for relative density? |
Specific gravity |
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What is the relative density of N.G. in its gaseous state? |
0.55 |
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What is the relative density of Propane in its gaseous state? |
1.52 |
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The boiling point of liquid propane is _________, vs natural gas, which is _________. |
-44 degrees F -260 degrees F |
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What is the ideal air to fuel ratio for complete combustion of N.G vs propane? |
N.G: 10-1 L.P: 23.5-1 |
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True or False? Propane combusts at 1000 BTU’s per cu. ft. Approx 2.5x hotter than Natural Gas. |
False Propane = 2520 BTU per cu ft Natural Gas = 1000 BTU per cu ft |
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What are the ignition temperatures of air-mixed propane and Natural Gas? |
Propane= 920 deg F Natural Gas= 1300 deg F |
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What is the typical pressure of a gas line entering a city gate station vs leaving the station? |
1500-2000 PSIG Vs 300 PSIG Note there are also intermediate, modified and low pressure lines for regular distribution throughout cities |
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What is the relative density of liquid natural gas & propane? |
NG: 0.3 Propane: 0.51 |
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What is the boiling point of water? |
212 F |
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What is the expansion factor of natural gas? |
1-600 x |
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What is the expansion rate of propane? |
1-270x |
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What is the definition of Heating Content? |
The amount of heat energy released by burning one cu ft of gas. It is measured in BTUs |
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What is the heating value of propane? |
2520 BTUs per cu ft |
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What is the difference between LEI and UEI? |
Lower vs Upper explosion limits = lowest vs highest ratios of fuel to air mixture that will support combustion |
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What is the LEI of propane vs Ng? |
Propane= 2.5-9.5 LG= 4-15% |
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Define combustion |
The rapid oxidization of a fuel gas to produce light and heat. |
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True or False? The maximum flame speed of NG is 12” per second, vs Propane @ 32” per second |
True |
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What are the products of incomplete combustion? |
Carbon monoxide Soot Aldehydes |
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What are the products of complete combustion? |
Carbon Dioxide Heat Light Oxygen Water vapour Nitrogen |
There needs to be excess oxygen in order to ensure complete combustion |
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What are the symptoms of CO ppisoning? |
Flu without the fever |
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What are possible reasons for the presence of Carbon Monoxide? |
- improper function/maintenance of an appliance (ask homeowner about health/appliance issues) - spillage of flue products (improper venting) - cracked heat exchanger - lack of fresh air supply |
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What is the minimum unacceptable levels of CO in an enclosed space? |
35 ppm (But in reality should be zero!) |
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True or False? Primary air is supplied prior to ignition and secondary air is supplied after combustion. |
False: Primary air is supplied prior to ignition and secondary air is supplied after ignition (around the flame) to complete the combustion |
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True or false Dilution air is air supplied in excess of combustion to ensure complete combustion |
False Dilution air is air allowed into a venting device to slow the speed of air flow through a vent, cooling it as a result. |
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True or false: Excess air is air supplied in excess of combustion to ensure complete combustion |
True |
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This tube is where the gas supply is premixed with air. |
Ventruri Tube (creates small vortex) |
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A luminous flame is ___________ in colour and is caused by _____________ supply. |
Yellow Fuel rich supply |
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Flame lifting is caused by ______________ conditions, and can be identified by ___________. |
- Air rich conditions (or an overfired burner). - noisy or broken flame |
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What causes flashback? |
When Gas/air flow velocity is less than the flame speed (12”/sec) |
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Propane tanks are tested by _________________, and have a relief pressure of 250 PSIG. |
TSSA |
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Propane cylinders are tested by _________________, and have a relief pressure of ________. |
- TC, DOT, CTC - 375 PSIG |
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What is the ratio for primary air (NG) |
10:1 |
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What is the ratio for primary air (NG) |
10:1 |
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What is the ratio for secondary air (NG)? |
5:1 |
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What is the ratio for primary air (NG) |
10:1 |
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What is the ratio for secondary air (NG)? |
5:1 |
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What is the ratio for dilution air (NG)? |
15:1 |
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Working pressure is: |
The gas pressure in the supply line while the appliance is running. |
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What is the required minimum pressure test strength of all gas hosing? |
350 psig |
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What is delta T a measurement of? |
It is the temperature difference between return air and supply air. |
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When are custom fitting sizes required for gas pipe sizing? |
When dealing with supply pressure over 2 psig. Use table B.11 for fittings. |
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Define BTU |
The amount of heat energy required to raise the temperature of 1 lb of water by 1 degree F at sealevel. |
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What is the purpose and colour symbol of an A Class fire extinguisher? |
Green Normal combustibles |
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What is the purpose and colour symbol of an A Class fire extinguisher? |
Green Normal combustibles |
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What is the colour symbol and purpose of a Class B fire extinguisher? |
Red Vapours/chemicals |
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What is the colour and purpose of a Class C fire extinguisher? |
Blue Electrical |
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What is the colour it and purpose of a Class D fire extinguisher? |
Yellow Combustible Metals |
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What is the colour and purpose of a Class K fire extinguisher? |
Yellow Kitchen fires / oils |
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