Question Answer Notes
True or false: The essential purposes of a ventilation system are to create airflows of sufficient quality and quantity, and to dilute contaminants to safe concentrations and remove them from the mine, as well as dilute heat and provide air conditioning. True  
Escapeways for underground mines are typically located in the ____? A. Exhaust airways; B. Shops & lunchrooms; C. Fresh air intake; D. Primary haulage drifts C. Fresh air intake  
Which statement is true about mine doors? A. They allow people and equipment through high traffic areas while still controlling airflow; B. They are often hung in pairs to form an airlock; C. They are always hung so ventilating air pressure will push them closed; D. All of the above D. All of the above Airlock: when 2 doors are installed in series to prevent short-circuiting of air flow during passage of men or equipment. Should be installed instead of single doors where interruptions of the ventilation circuit are frequent and serious or the pressure drop is high. Installed in entries and haulageways serving as major airways or located near them. The distance between doors should be made great enough to accommodate the longest train of cars or equipment passing. Mechanical doors are usually prevented from opening or equipped with a warning device when one door of an airlock is open and an attempt is made to open the other.
One of the main objectives of a ventilation system is to dilute pollutants to a safe level and then remove them. Name three common pollutants that may be encountered. Gases; products of combustion; dusts; heat and humidity; radioactive solids and byproducts; DPM  
Two main categories of airflow control devices in a ventilation system are active devices and passive devices. Which are not passive devices? A. Stoppings & seals; B. Regulators & air crossings; C. Main fans & booster fans; D. Air doors & air locks C. Main fans & booster fans Main fans handle the whole mine airflow and are commonly sited on the surface. While main fans generally handle all the mine airflow, other fans are used in mines to boost the airflow energy to allow air to be circulated over greater distances. These are called booster fans and generally serve specific areas of the mine.
Name one factor that affects the atmosphere in a mine. Vehicles; people; fires; ventilation  
Mechanical ventilation is required in underground mines to support these two things. Life; equipment  
Mechanical ventilation is used to control humidity, remove dust particles, dilute gases, and mitigate this potentially hazardous environmental condition. Heat  
In underground hard rock mining, primary escapeway routes should always be located in this type of working. Fresh air intake  
What are three potential sources of CO in an underground mine? Fire; diesel equipment; blasting  
What key component of a ventilation system is used to control airflow direction or build up air pressure? Air doors, regulators, or stoppings Of the 23,824 passenger vehicle occupants killed in 2020, 51% were not wearing seat belts — a 4% increase from 2019.
The fresh air intake is typically associated with: A. Secondary escape ways; B. Primary haulage (e.g., belt lines); C. Primary escape ways; D. All of the above C. Primary escape ways  
Which ventilation method is most commonly used in modern mines? A. Natural ventilation; B. Shaft bottom thermal induction; C. Mechanical fan systems; D. None of the above C. Mechanical fan systems  
A copy of the ventilation map is handy . . . A. To know where mine phones, SCSRs, and refuge chambers are located; B. To understand where all the best hiding places are; C. To understand primary and secondary escape routes; D. So I can improve my odds of escape in the event of an emergency evacuation; E. A, C, and D; F. All of the above E. A, C, and D  
Which of the following is the least effective ventilation control device? A. Stoppings; B. Muck piles; C. Overcasts; D. Air doors; E. Brattice cloth B. Muck piles  
If you measure 1000 feet of air using an anemometer over a two-minute traverse in a heading that measures 147 square feet, what is the quantity? A. 147,000 cfm; B. 73,500 cfm; C. 294,000 cfm; D. 500 fpm; E. None of the above B. 73,500 cfm  
True or false: For a mine with naturally occurring gas in the strata, such as with methane in coal, the best type of ventilation system would be positive pressure because it keeps the gas trapped in the rock. False  
True or false: Under 30 CFR 75, it is acceptable for miners and supervisors to alter the ventilation in their working area after giving fifteen minutes notice to mine management. False  
Smoke and contaminated air in the mine intake airway in an indication of what? A. Fire underground; B. The ventilation system has been compromised; C. Primary and secondary escape routes may no longer be safe; D. All of the above D. All of the above  
Effective ventilation can be a deterrent against harmful gases in the mine by: A. Preventing it from stratifying in hazardous concentrations; B. Diluting it below the Threshold Limit Value; C. Promoting liberation of the gas from the in-situ formation; D. Supporting an ongoing concentration of airborne dust which makes the gas easier to see; E. All of the above; F. A, B, and C F. A, B, and C  
Why is ventilation necessary in an underground mine? A. It provides a respirable atmosphere for miners; B. It controls hazardous gases and dusts; C. It dries the air in the mine; D. A and B; E. A and C D. A and B  
Important information contained on the mine ventilation map could include: A. Direction of airflow and quantities; B. Location of refuge chambers and emergency escape routes; C. The location of SCSR caches, mine phones, man-doors, etc.; D. Any or all of the above D. Any or all of the above  
Which of the following is an example of a technique for controlling ventilation in an underground mine? A. Overcasts and undercasts; B. Air doors; C. Bulkheads; D. Line brattice; E. All of the above; F. None of the above E. All of the above  
How often must mine ventilation plans must be reviewed and submitted to MSHA for approval? A. Every six months; B. Every two years or when there is a change in airflow direction in the mine; C. At least annually or sooner depending on changes in the mine; D. The mine ventilation plan is approved permanently and does not require re-submitting to MSHA C. At least annually or sooner depending on changes in the mine  
Why is ventilation important in a mine? A. Mine gases could build up; B. The product you are mining needs air; C. There could be low oxygen; D. Both A and C; E. None of the above D. Both A and C  
Should you ever alter the ventilation system in a mine? A. Yes; B. No; C. If there is an emergency B. No