Composition of Air

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What percentage of the air at sea level is comprised of oxygen?

78.09%

0.03%

0.94%

20.94% (correct)

Which of the following gases is NOT typically found in pure, dry air at sea level?

Helium

Nitrogen

Methane (correct)

Hydrogen

What is the primary mechanism by which gases can affect humans in a mine?

Toxic properties

Combustible properties

Displacement of oxygen (correct)

Explosive properties

What is a potential source of methane in a mine?

Diffusion from ore or country rock Signup and view all the answers

What is the primary purpose of adequate positive ventilating currents in a mine?

To prevent the accumulation of hazardous gases Signup and view all the answers

What is the minimum percentage of oxygen required in the atmosphere at the workplace?

19.5% Signup and view all the answers

What is the explosive range of propane?

2.4%–9.5% Signup and view all the answers

At what percentage of oxygen in the atmosphere can a person experience dizziness, buzzing noise, and rapid pulse?

15% Signup and view all the answers

What is the chemical symbol for propane?

C₃H₈ Signup and view all the answers

What happens to the heart shortly after breathing stops due to oxygen deficiency?

It stops Signup and view all the answers

What unit is used to measure airborne particulate concentrations?

Milligrams per cubic metre of air Signup and view all the answers

What is the standard substance used for measuring relative density of gases?

Air Signup and view all the answers

What is the term for the minimum concentration of a gas or vapour in air that will ignite when exposed to an ignition source?

Lower Explosive Limit Signup and view all the answers

What is the pH of pure water?

7 Signup and view all the answers

What property of air allows it to be compressed to a liquid or frozen to a solid?

Weight Signup and view all the answers

What happens when nitric oxide (NO) is exposed to air?

Nitrogen dioxide (NO₂) is formed Signup and view all the answers

What is the minimum exposure level of nitrogen dioxide that can cause immediate throat irritation?

60 PPM Signup and view all the answers

What is the effect of nitrogen on humans?

It has no physiological effect Signup and view all the answers

What is the colour of nitrogen dioxide in high concentrations?

Reddish brown Signup and view all the answers

What is the effect of inhaling nitrogen dioxide in high concentrations?

It causes bronchitis or pneumonia Signup and view all the answers

What is the primary effect of inhaling high concentrations of MAPP?

Anesthesia-like effect Signup and view all the answers

What is the minimum percentage of methane required to isolate electrical circuits in a work environment?

1.25% Signup and view all the answers

What is a common characteristic shared by MAPP, methane, and nitrogen?

Colourless and odourless Signup and view all the answers

What is a possible source of methane gas?

Diamond drilling operations Signup and view all the answers

What is a potential hazard of skin contact with liquid MAPP?

Tissue freezing or frostbite Signup and view all the answers

Which gas is formed through the decomposition of organic matter, carbonaceous rock, decaying timber, and is a component of natural gas?

Methane Signup and view all the answers

Which gas has a characteristic 'bitter almond' odour?

Hydrogen Cyanide Signup and view all the answers

Which gas is heavier than air and has a characteristic 'rotten egg' odour?

Hydrogen Sulphide Signup and view all the answers

Which gas is formed through the reaction of nitrogen and hydrogen in the presence of a catalyst?

Ammonia Signup and view all the answers

Which gas is a constituent of air, but can be formed through the decomposition of some sulphur compounds, blasting sulphide ores, and decomposition of vegetable matter in water?

Hydrogen Sulphide Signup and view all the answers

What is the primary source of hydrogen gas at mines?

Battery charging Signup and view all the answers

What is the explosive range of hydrogen gas?

4%–75% with 5% oxygen Signup and view all the answers

What is the characteristic of hydrogen cyanide gas?

Colourless, with a distinctive odour of bitter almonds Signup and view all the answers

What is the effect of hydrogen gas on humans?

It causes asphyxiation due to an oxygen-deficient atmosphere Signup and view all the answers

What should be done to stop a pinhole leak in a chlorine gas cylinder?

Drive a tapered hardwood peg or metal drift pin into the hole Signup and view all the answers

What is the effect of chlorine gas on humans at a concentration of 16–30 PPM?

Chest pain, vomiting, coughing, and difficulty breathing Signup and view all the answers

What is the chemical symbol for chlorine gas?

Cl₂ Signup and view all the answers

What is the purpose of turning a chlorine gas cylinder so that only gas is escaping before plugging the leak?

To make it easier to drive the plug into the hole Signup and view all the answers

What should be done after temporarily stopping a pinhole leak in a chlorine gas cylinder?

Empty the cylinder as quickly as possible Signup and view all the answers

What is the effect of chlorine gas on humans at a concentration of 0–6 PPM?

Eye irritation Signup and view all the answers

What is the primary factor that affects the strength of clear blue lake-ice?

The movement of water beneath the ice Signup and view all the answers

What should be done to determine the strength of the ice before traveling on it?

Test the thickness of the ice frequently in various locations Signup and view all the answers

What type of ice is the strongest form of ice?

Clear or natural ice Signup and view all the answers

What happens when a vehicle travels on ice?

It creates a resonance wave in the underlying water Signup and view all the answers

What percentage should loads be reduced by when traveling on clear blue river-ice?

15% Signup and view all the answers

What is the maximum allowable mass of a vehicle in motion for an ice thickness of 20 cm?

10,000 kg Signup and view all the answers

What is the primary concern when driving a vehicle on ice roads?

The weight and speed of the vehicle affecting the size and speed of the wave Signup and view all the answers

What is the speed limit for an empty vehicle on ice roads?

35 km/h Signup and view all the answers

What is the potential consequence of the resonance wave on the ice?

The ice will be more likely to fail Signup and view all the answers

What is the formula used to determine the maximum allowable mass of a vehicle on ice?

M = 4 × h2 Signup and view all the answers

What is the primary area of heat loss from the body?

Head and neck Signup and view all the answers

What is the purpose of the H.E.L.P. technique?

To reduce heat loss from the body Signup and view all the answers

What happens to the heart rate and respiration rate as hypothermia progresses?

They decrease rapidly Signup and view all the answers

What is a critical consideration when conserving body heat?

Protecting the head and neck Signup and view all the answers

What is the eventual outcome if hypothermia is left untreated?

All of the above Signup and view all the answers

What is the primary factor that affects the strength of clear blue lake-ice?

Temperature Signup and view all the answers

What should be done to determine the strength of the ice before traveling on it?

Drill a hole to check the thickness Signup and view all the answers

What happens when a vehicle travels on ice?

The ice is more likely to crack or break Signup and view all the answers

What is the term for the minimum concentration of a gas or vapour in air that will ignite when exposed to an ignition source?

Flammable range Signup and view all the answers

What type of ice is the strongest form of ice?

Clear blue lake-ice Signup and view all the answers

What is the expected survival time if a person is exposed to water with a temperature between 0°C and 5°C?

15–30 minutes Signup and view all the answers

At what water temperature range is exhaustion or unconsciousness expected to occur in less than 15 minutes?

0°C Signup and view all the answers

What is a characteristic of someone experiencing moderate hypothermia?

Mild confusion and stumbling pace Signup and view all the answers

What is the minimum core temperature range for someone to be classified as having mild hypothermia?

36.1–35.0°C Signup and view all the answers

What is a common symptom of someone experiencing severe hypothermia?

Sluggish thinking and amnesia Signup and view all the answers

What is a primary factor that contributes to the development of hypothermia?

All of the above Signup and view all the answers

What is a common characteristic of people who fail to recognize symptoms of hypothermia?

They are people who die in the outdoors Signup and view all the answers

What is the result when the body loses heat faster than it can produce it?

Hypothermia Signup and view all the answers

What are some of the visible symptoms that indicate the onset of hypothermia?

Shivering, confusion, and drowsiness Signup and view all the answers

What happens when the body is exposed to cold, wind, or water?

Heat loss increases Signup and view all the answers

What is the primary hazard associated with oxygen deficiency during a mine fire?

Oxygen replacement by toxic or inert gases Signup and view all the answers

Which gas is always present during a mine fire and gives little or no warning of its presence?

Carbon monoxide Signup and view all the answers

What is the primary effect of sulphur dioxide gas during a mine fire?

It gives advance warning in low concentrations Signup and view all the answers

Which gas is not produced by mine fires or explosions but may cause them?

Methane Signup and view all the answers

What is the primary hazard associated with methane gas in a mine?

It is a major hazard during rescue or recovery operations Signup and view all the answers

What is the primary concern during and after mine fires?

Carbon monoxide poisoning and oxygen deficiency Signup and view all the answers

What is the primary characteristic of hydrogen sulphide gas?

It sometimes indicates the presence of methane Signup and view all the answers

Which gas is formed through the reaction of nitrogen and hydrogen in the presence of a catalyst?

Ammonia Signup and view all the answers

What is the primary factor that affects the strength of clear blue lake-ice?

Temperature Signup and view all the answers

What is the primary mechanism by which gases can affect humans in a mine?

Oxygen replacement by toxic or inert gases Signup and view all the answers

Composition of Air

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Questions and Answers

What percentage of the air at sea level is comprised of oxygen?

Which of the following gases is NOT typically found in pure, dry air at sea level?

What is the primary mechanism by which gases can affect humans in a mine?

What is a potential source of methane in a mine?

What is the primary purpose of adequate positive ventilating currents in a mine?

What is the minimum percentage of oxygen required in the atmosphere at the workplace?

What is the explosive range of propane?

At what percentage of oxygen in the atmosphere can a person experience dizziness, buzzing noise, and rapid pulse?

What is the chemical symbol for propane?

What happens to the heart shortly after breathing stops due to oxygen deficiency?

What unit is used to measure airborne particulate concentrations?

What is the standard substance used for measuring relative density of gases?

What is the term for the minimum concentration of a gas or vapour in air that will ignite when exposed to an ignition source?

What is the pH of pure water?

What property of air allows it to be compressed to a liquid or frozen to a solid?

What happens when nitric oxide (NO) is exposed to air?

What is the minimum exposure level of nitrogen dioxide that can cause immediate throat irritation?

What is the effect of nitrogen on humans?

What is the colour of nitrogen dioxide in high concentrations?

What is the effect of inhaling nitrogen dioxide in high concentrations?

What is the primary effect of inhaling high concentrations of MAPP?

What is the minimum percentage of methane required to isolate electrical circuits in a work environment?

What is a common characteristic shared by MAPP, methane, and nitrogen?

What is a possible source of methane gas?

What is a potential hazard of skin contact with liquid MAPP?

Which gas is formed through the decomposition of organic matter, carbonaceous rock, decaying timber, and is a component of natural gas?

Which gas has a characteristic 'bitter almond' odour?

Which gas is heavier than air and has a characteristic 'rotten egg' odour?

Which gas is formed through the reaction of nitrogen and hydrogen in the presence of a catalyst?

Which gas is a constituent of air, but can be formed through the decomposition of some sulphur compounds, blasting sulphide ores, and decomposition of vegetable matter in water?

What is the primary source of hydrogen gas at mines?

What is the explosive range of hydrogen gas?

What is the characteristic of hydrogen cyanide gas?

What is the effect of hydrogen gas on humans?

What should be done to stop a pinhole leak in a chlorine gas cylinder?

What is the effect of chlorine gas on humans at a concentration of 16–30 PPM?

What is the chemical symbol for chlorine gas?

What is the purpose of turning a chlorine gas cylinder so that only gas is escaping before plugging the leak?

What should be done after temporarily stopping a pinhole leak in a chlorine gas cylinder?

What is the effect of chlorine gas on humans at a concentration of 0–6 PPM?

What is the primary factor that affects the strength of clear blue lake-ice?

What should be done to determine the strength of the ice before traveling on it?

What type of ice is the strongest form of ice?

What happens when a vehicle travels on ice?

What percentage should loads be reduced by when traveling on clear blue river-ice?

What is the maximum allowable mass of a vehicle in motion for an ice thickness of 20 cm?

What is the primary concern when driving a vehicle on ice roads?

What is the speed limit for an empty vehicle on ice roads?

What is the potential consequence of the resonance wave on the ice?

What is the formula used to determine the maximum allowable mass of a vehicle on ice?

What is the primary area of heat loss from the body?

What is the purpose of the H.E.L.P. technique?

What happens to the heart rate and respiration rate as hypothermia progresses?

What is a critical consideration when conserving body heat?

What is the eventual outcome if hypothermia is left untreated?

What is the primary factor that affects the strength of clear blue lake-ice?

What should be done to determine the strength of the ice before traveling on it?

What happens when a vehicle travels on ice?

What is the term for the minimum concentration of a gas or vapour in air that will ignite when exposed to an ignition source?

What type of ice is the strongest form of ice?

What is the expected survival time if a person is exposed to water with a temperature between 0°C and 5°C?

At what water temperature range is exhaustion or unconsciousness expected to occur in less than 15 minutes?

What is a characteristic of someone experiencing moderate hypothermia?

What is the minimum core temperature range for someone to be classified as having mild hypothermia?

What is a common symptom of someone experiencing severe hypothermia?

What is a primary factor that contributes to the development of hypothermia?

What is a common characteristic of people who fail to recognize symptoms of hypothermia?

What is the result when the body loses heat faster than it can produce it?

What are some of the visible symptoms that indicate the onset of hypothermia?

What happens when the body is exposed to cold, wind, or water?

What is the primary hazard associated with oxygen deficiency during a mine fire?

Which gas is always present during a mine fire and gives little or no warning of its presence?

What is the primary effect of sulphur dioxide gas during a mine fire?

Which gas is not produced by mine fires or explosions but may cause them?

What is the primary hazard associated with methane gas in a mine?

What is the primary concern during and after mine fires?

What is the primary characteristic of hydrogen sulphide gas?