Practice Test for Task 70 -
Characteristics of Natural Gas
90% - answer How much methane is in natural gas?
4% - answer What is the percentage of ethane in natural gas?
4% - answer There is __________% nitrogen in natural gas.
1% - answer What is the percentage of propane and heavier hydrocarbons in natural
gas?
Ethane - answer What is the one component that distinguishes natural gas from other
gasses?
Tasteless
Colorless
Odorless
Non-toxic
Lighter than air - answer What are the five characteristics of natural gas?
Impurities - answerWhat is removed from natural gas when it is processed?
Mercaptan - answerWhat is added to natural gas when it is processed?
An organic compound added to natural gas - answerWhat is mercaptan?
It gives it an identifiable odor for safety reasons - answerWhat benefit does mercaptan
give to natural gas?
If gas passes through areas of decayed matter
Various soil compositions
New pipelines - answerWhat are 3 reasons that gas odor intensity may be decreased or
masked?
abnormal operating condition - answerImproper odorization is an __________
____________ __________.
An under-odorization condition - answerWhat could a release of gas with no odor
detected indicate?
, It rises quickly and mixes with air - answerWhat happens when natural gas is released
into the atmosphere?
At ground level - answerWhere will propane, gasoline and fuel oil settle?
path of least resistance - answerNatural gas will follow the ______ __ _____
__________.
Soil conditions - answerWhat plays a big role in the way gas travels?
Prevents it from traveling upwards and causes it to accumulate underground. -
answerWhat does moist soil do to gas?
Dry soil - answerWhat type of soil allows gas to move freely?
It forms a barrier at ground level that does not allow leaking gas to rise. - answerWhat
does frozen soil do to gas?
Yes; through soft trenches and cracks in foundations - answerCan gas migrate
sideways? if so, through what?
No; it can accumulate far from the initial leak. It can travel through sewers and
underground duct lines. - answerDoes a gas leak always stay near its source? if not,
how does it travel?
It expands - answerWhat happens to natural gas when it is heated?
It contracts - answerWhat happens to natural gas when it is cooled?
1 degree Fahrenheit - answerHow far will the gas temperature drop for every 14psi
reduction in pressure?
A frost ball of frozen soil can form around underground pipe. - answerWhat can happen
to soil if gas falls below 32 degrees Fahrenheit?
It causes undue stress to the pipe. - answerWhat does a frost ball of frozen soil do an
underground pipe?
They raise the gas temperature to keep regulated gas above 32 degrees Fahrenheit. -
answerWhat do pipeline heaters do before reducing pressure? Why?
Natural gas
Air
Heat - answerWhat 3 things must be present for combustion to occur?
Characteristics of Natural Gas
90% - answer How much methane is in natural gas?
4% - answer What is the percentage of ethane in natural gas?
4% - answer There is __________% nitrogen in natural gas.
1% - answer What is the percentage of propane and heavier hydrocarbons in natural
gas?
Ethane - answer What is the one component that distinguishes natural gas from other
gasses?
Tasteless
Colorless
Odorless
Non-toxic
Lighter than air - answer What are the five characteristics of natural gas?
Impurities - answerWhat is removed from natural gas when it is processed?
Mercaptan - answerWhat is added to natural gas when it is processed?
An organic compound added to natural gas - answerWhat is mercaptan?
It gives it an identifiable odor for safety reasons - answerWhat benefit does mercaptan
give to natural gas?
If gas passes through areas of decayed matter
Various soil compositions
New pipelines - answerWhat are 3 reasons that gas odor intensity may be decreased or
masked?
abnormal operating condition - answerImproper odorization is an __________
____________ __________.
An under-odorization condition - answerWhat could a release of gas with no odor
detected indicate?
, It rises quickly and mixes with air - answerWhat happens when natural gas is released
into the atmosphere?
At ground level - answerWhere will propane, gasoline and fuel oil settle?
path of least resistance - answerNatural gas will follow the ______ __ _____
__________.
Soil conditions - answerWhat plays a big role in the way gas travels?
Prevents it from traveling upwards and causes it to accumulate underground. -
answerWhat does moist soil do to gas?
Dry soil - answerWhat type of soil allows gas to move freely?
It forms a barrier at ground level that does not allow leaking gas to rise. - answerWhat
does frozen soil do to gas?
Yes; through soft trenches and cracks in foundations - answerCan gas migrate
sideways? if so, through what?
No; it can accumulate far from the initial leak. It can travel through sewers and
underground duct lines. - answerDoes a gas leak always stay near its source? if not,
how does it travel?
It expands - answerWhat happens to natural gas when it is heated?
It contracts - answerWhat happens to natural gas when it is cooled?
1 degree Fahrenheit - answerHow far will the gas temperature drop for every 14psi
reduction in pressure?
A frost ball of frozen soil can form around underground pipe. - answerWhat can happen
to soil if gas falls below 32 degrees Fahrenheit?
It causes undue stress to the pipe. - answerWhat does a frost ball of frozen soil do an
underground pipe?
They raise the gas temperature to keep regulated gas above 32 degrees Fahrenheit. -
answerWhat do pipeline heaters do before reducing pressure? Why?
Natural gas
Air
Heat - answerWhat 3 things must be present for combustion to occur?
