Mine Gases Everything you wanted to know about gases but were afraid to ask! Download this in MS Word format

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Methane	Carbon Monoxide	Oxides of Nitrogen
Hydrogen	Oxygen	Nitrogen
Diffusion of Gases	Carbon Dioxide	Sulfur Dioxide
Hydrogen Sulfide	Mine Damps	Miscellaneous

Methane
Q	Where is Methane most likely to be found in a mine?
A	Near the roof, as it is lighter than air.
Q	What is a flammable mixture of methane and air which can either burn or explode when ignited called?
A	Firedamp
Q	What is the ignition temperature of methane?
A	1100-1380o F.
Q	What instruments are most often used in detecting methane?
A	The flame safety lamp and methane detectors.
Q	What is the least percentage of methane that can be detected with a flame safety lamp?
A	About one percent (1%).
Q	What effect does the presence of methane have upon the explosibility of coal dust?
A	The coal dust is more easily ignited and the force of the explosion is greater.
Q	What effect does coal dust in the air have upon the explosibility of methane?
A	The lower explosive limit is decreased.
Q	What dangerous gas is most likely to be encountered above a pillar fall?
A	Methane.
Q	What effect does the presence of methane have upon the explosibility of coal dust?
A	The coal dust is more easily ignited and the force of the explosion is greater.
Q	What effect does coal dust in the air have upon the explosibility of methane?
A	The lower explosive limit is decreased.
Q	What dangerous gas is most likely to be encountered above a pillar fall?
A	Methane.
Q	Why will methane accumulate in an inadequately ventilated place?
A	It is lighter than air and will rise and stratify if not properly diffused.
Q	What is the principle combustible gas usually found in coal mines?
A	Methane.
Q	Is methane (CH4) poisonous?
A	No
Q	What is the color of methane?
A	Methane is colorless.
Q	Which is the heaviest, one cubic foot of methane or one cubic foot of air?
A	One cubic foot of air.
Q	What gas is found near the roof and cavities on falls?
A	Methane (CH4).
Q	What gas is odorless, tasteless, non-toxic, colorless and explosive in the concentration of 5%-15%?
A	Methane
Q	What is the source of methane in coal mines?
A	It is liberated from coal and adjoining strata.
Q	What is the specific gravity of methane?
A	0.555.
Q	Where is methane usually found in mines?
A	Along the roof, to the rises, in the vicinity of working faces, in dead ends and above falls.
Q	Is methane an explosive by itself?
A	No. Oxygen is required to support combustion.
Q	Why can there be no explosion when the percentage of methane is greater than fifteen percent (15%)?
A	Because the amount of oxygen present is insufficient for rapid combustion to occur.
Q	How can methane gas be detected in a coal mine?
A	Chemical analysis, flame safety lamp and methane detectors.
Q	What is the explosive range of methane?
A	Five to fifteen percent.
Q	What is the percentage of methane required for maximum explosive violence?
A	Ten percent (10%).
Carbon Monoxide
Q	What percent of carbon monoxide can cause death in less than one hour?
A	0.4 percent or more.
Q	What is the ignition temperature of Carbon monoxide?
A	1100 degrees F.
Q	Why are small quantities of carbon monoxide injurious?
A	Because it is not easily eliminated and it accumulates in the blood.
Q	What is the specific gravity of carbon monoxide?
A	0.967.
Q	What is carbon monoxide (CO)?
A	It is a colorless, odorless, tasteless, combustible, and poisonous gas.
Q	How can carbon monoxide be detected?
A	By carbon monoxide detectors, and by analysis.
Q	Workers should not be employed for a period of 8 hours where the carbon monoxide content exceeds what?
A	50 PPM (0.005%)
Q	What percentage of carbon monoxide might produce symptoms of poisoning if breathed indefinitely?
A	0.01%.
Q	What is the source of carbon monoxide?
A	It is the product of incomplete combustion (combustion with an insufficiency of oxygen).
Q	When is carbon monoxide most likely to be found in mines?
A	When there is a mine fire or after an explosion.
Q	What does the presence of CO in a sealed mine area indicate?
A	A fire.
Q	What percentage of blood saturation by Carbon monoxide (CO) will cause death?
A	70% -80%.
Q	The explosive range of carbon monoxide is what?
A	12.5-74 percent.
Q	What percentage of carbon monoxide will produce slight symptoms in several hours?
A	200 PPM (.02%).
Q	What percentage of carbon monoxide will produce discomfort in two or three hours?
A	400 PPM (.04%).
Q	What percentage of carbon monoxide will produce a tendency to stagger in one and one-half (12) hours?
A	1200 PPM (0.12%).
Q	What percentage of carbon monoxide will produce symptoms of unconsciousness in thirty (30) minutes?
A	2000-2500 PPM (.20%-.25%).
Q	How much greater affinity does hemoglobin have for carbon monoxide than for oxygen?
A	About three hundred (300) times.
Q	What is the principal poisonous gas produced by explosions?
A	Carbon monoxide.
Q	What effect does carbon monoxide have on life?
A	It is extremely poisonous.
Q	How does carbon monoxide cause injury to life?
A	By combining with the hemoglobin of the blood and excluding oxygen.
Oxides of Nitrogen
Q	How are oxides of Nitrogen formed?
A	From the use of explosives in mines.
Q	How do oxides of nitrogen cause death?
A	Causes fluid to accumulate in lungs resulting in asphyxia.
Q	How are results from analysis of oxides of nitrogen reported?
A	In terms of nitrogen dioxide.
Q	List the threshold limit value for oxides of nitrogen.
A	5 ppm.
Hydrogen
Q	What are the sources of Hydrogen in a mine?
A	Charging batteries, mine fires, and explosions.
Q	Hydrogen is always present after what type of explosion?
A	Coal dust explosions.
Q	Is hydrogen explosive?
A	Yes.
Q	What is the specific gravity of hydrogen?
A	It is the lightest of all gases with a specific gravity of 0.0695
Q	Name the gas which is generated from a storage battery.
A	Hydrogen (H2).
Q	What is the explosive range of hydrogen?
A	4.1 to 74 percent.
Q	How is hydrogen detected?
A	By chemical analysis.
Q	Is hydrogen flammable?
A	Yes.
Miscellaneous
Q	Write down the chemical symbols of methane and hydrogen sulfide.
A	CH4 and H2S
Q	Name the non-explosive gases found in coal mines.
A	Carbon dioxide (CO2) and Nitrogen (N2)
Q	Name the explosive gases found in bituminous coal mines in Pennsylvania.
A	Methane (CH4), Carbon Monoxide (CO), and Hydrogen Sulfide (H2S).
Q	What is TLV?
A	Threshold limit value.
Q	Convert 0.01 percent of carbon monoxide to ppm.
A	100 ppm.
Q	What is noxious gas?
A	Any gas in the air which is harmful to life when inhaled.
Q	What is the percentage of oxygen below which no explosion of a methane air-mixture can occur?
A	Twelve percent (12%).
Q	What effect does an atmosphere with a reduced oxygen content have upon the explosibility of methane?
A	A greater percentage of methane is necessary to start an explosion in an atmosphere which contains less than the normal percentage of oxygen.
Oxygen
Q	What percentage of the earth's atmosphere is oxygen?
A	20.94 percent oxygen.
Q	A sealed area of a coal mine after a period of time will be found to have the absence of what?
A	Oxygen.
Q	Can there be a mine fire or an explosion without the presence of oxygen?
A	No
Q	Mine air should not contain less than what percentage of oxygen?
A	19.5%.
Q	How does the body receive oxygen?
A	Through breathing, the oxygen is taken up by the hemoglobin of the blood and carried to all parts of the body.
Q	What supports the chemical reaction that produces fires and explosions?
A	Oxygen.
Q	What percent oxygen can a person most easily work in?
A	20.9%
Q	What percent oxygen will a person breathe faster and deeper while at work?
A	17 percent.
Q	A flame safety lamp will go out when the oxygen percentage is below what?
A	16 percent.
Q	What element in the air is essential for life?
A	Oxygen.
Q	How does the body receive oxygen?
A	By breathing, oxygen is absorbed by the blood and carried to the cells of the body.
Q	When is the oxygen (O2) level in air considered to be dangerous?
A	When the Oxygen (O2) level falls below 16%.
Nitrogen
Q	What percent of the earth's atmosphere is nitrogen?
A	78.09 % Nitrogen
Q	What is the threshold limit value of nitrogen?
A	81%.
Q	What is nitrogen?
A	It is a tasteless, odorless and colorless gas which will neither support life nor combustion.
Q	Is nitrogen combustible?
A	No.
Q	What effect does nitrogen have towards propagating an explosion?
A	None
Q	What effect does nitrogen have upon life?
A	It has no effect. except when it depletes oxygen to the extent that there is a deficiency of oxygen.
Q	Does nitrogen have an ignition temperature?
A	No, nitrogen will not explode.
Diffusion of Gases
Q	Once two or more gases mix uniformly will they separate or come apart?
A	No
Q	Define the term diffusion of gases.
A	Diffusion is a phenomenon by which gases mix by natural forces.
Q	What is the law of diffusion?
A	The rate of diffusion varies inversely as the square root of specific gravity.
Q	What is stratification?
A	When gases do not diffuse completely, layers of gas stratify horizontally.
Q	What type of atmosphere is easy for the detection of a gas a diffused one or a stratified one?
A	A stratified one.
Carbon Dioxide
Q	Is carbon dioxide combustible?
A	No.
Q	What is the specific gravity of carbon dioxide?
A	1.529
Q	Where might concentrated accumulations of carbon dioxide ordinarily be found?
A	Near the floor, in inadequately ventilated places.
Q	What effect does carbon dioxide have upon life?
A	Respiration is increased as concentration of carbon dioxide increases.
Q	How is carbon dioxide detected?
A	Usually by chemical analysis.
Q	What is carbon dioxide (CO2)?
A	Carbon dioxide is a colorless and odorless gas formed by the chemical combination of carbon and oxygen.
Q	How is carbon dioxide formed in a mine?
A	By combustion, by breathing of miners and animals, by decay of vegetable and animal matter, by the oxidation of coal and by chemical action of acid water on carbonates.
Q	What is a product of complete combustion?
A	Carbon dioxide.
Q	Where might concentrated accumulations of carbon dioxide ordinarily be found?
A	Near the floor, in inadequately ventilated places.
Q	What effect does carbon dioxide have upon life?
A	Respiration is increased as concentration of carbon dioxide increases.
Q	How is carbon dioxide detected?
A	Usually by chemical analysis
Q	What is carbon dioxide (CO2)?
A	Carbon dioxide is a colorless and odorless gas formed by the chemical combination of carbon and oxygen.
Q	How is carbon dioxide formed in a mine?
A	By combustion, by breathing of miners and animals, by decay of vegetable and animal matter, by the oxidation of coal and by chemical action of acid water on carbonates.
Q	What is a product of complete combustion?
A	Carbon dioxide
Q	What is the chemical symbol of carbon dioxide?
A	CO2
Sulfur Dioxide
Q	How is sulfur dioxide formed in a mine?
A	By burning coal containing pyrites
Q	What is the specific gravity of sulfur dioxide?
A	2.263.
Q	What is the particular danger of sulfur dioxide?
A	It is extremely poisonous even in small amounts
Q	How is sulfur dioxide detected?
A	By the sense of smell and its effect on the air passages.
Q	What is the first effect on a person exposed to sulfur dioxide?
A	It is extremely irritating and suffocating and is intolerable to breathe.
Q	Is sulfur dioxide combustible?
A	No, it is incombustible.
Q	Is sulfur dioxide soluble in water?
A	Yes.
Hydrogen Sulfide
Q	What are the properties of hydrogen sulfide?
Q	Poisonous and colorless with an odor like rotten eggs
Q	What mine gas can be detected by its odor?
A	Hydrogen sulfide
Q	What is the origin of hydrogen sulfide?
A	It is liberated by burning explosives containing sulfur such as black powder or dynamite.
Q	How can hydrogen sulfide be detected other than by sense of smell?
A	By the hydrogen sulfide detector or by paper dipped in acetate of lead. which will turn black immediately on exposure to hydrogen sulfide.
Q	What distinctive odor does hydrogen sulfide gas smell like?
A	Smells like rotten eggs.
Q	What is the specific gravity of hydrogen sulfide?
A	1.191
Q	What is the explosive range of Hydrogen Sulfide?
A	4.3% to 45%.
Q	Is hydrogen sulfide poisonous?
A	Yes, it is extremely poisonous even in small amounts.
Q	What is the immediate effect of hydrogen sulfide on a person?
A	It is extremely irritating to the eyes.
Q	What is the threshold limit value of hydrogen sulfide?
A	10 PPM.
Q	Among methane, carbon monoxide, and hydrogen sulfide, which one has the lowest ignition temperature?
A	Hydrogen Sulfide (700°F).
Mine Damps
Q	What is meant by the term "black damp"?
A	An atmosphere deficient in oxygen.
Q	What is the effect of black damp' on flame safety lamp?
A	The flame of a safety lamp is dimmed or extinguished depending on concentration of gases present.
Q	What is the most simple and safe test for the presence of black damp?
A	A flame safety lamp.
Q	Stink damp refers to which gas?
A	Hydrogen sulfide
Q	White damp refers to which gas?
A	Carbon monoxide.