# 4b051 Bioenvironmental Engineering Journeyman CDC Ure Questions Vol. 5

Approved & Edited by ProProfs Editorial Team
The editorial team at ProProfs Quizzes consists of a select group of subject experts, trivia writers, and quiz masters who have authored over 10,000 quizzes taken by more than 100 million users. This team includes our in-house seasoned quiz moderators and subject matter experts. Our editorial experts, spread across the world, are rigorously trained using our comprehensive guidelines to ensure that you receive the highest quality quizzes.
| By Mav_2591
M
Mav_2591
Community Contributor
Quizzes Created: 5 | Total Attempts: 4,101
Questions: 100 | Attempts: 648

Settings

• 1.

### In ventilation work, what pressure is exerted outward against the interior surface of an enclosure?

• A.

Positive static.

• B.

Negative static.

• C.

Positive velocity.

• D.

Negative velocity.

A. Positive static.
Explanation
Positive static pressure is exerted outward against the interior surface of an enclosure in ventilation work. This means that the pressure inside the enclosure is higher than the pressure outside, causing air to be pushed outwards. This can be achieved by using fans or other ventilation equipment to increase the pressure inside the enclosure. Positive static pressure is commonly used to prevent the entry of contaminants or to maintain a specific air quality within the enclosure.

Rate this question:

• 2.

### The value for velocity pressure in a ventilation system is

• A.

Always positive.

• B.

Always negative.

• C.

Negative on the blowing side.

• D.

Negative on the exhausting side.

A. Always positive.
Explanation
In a ventilation system, velocity pressure refers to the pressure exerted by the moving air due to its velocity. Since velocity is always a positive value, the velocity pressure will also be positive. This is because the pressure exerted by the moving air is always greater than the static pressure of the surrounding air. Therefore, the correct answer is always positive.

Rate this question:

• 3.

### Less resistance and better contaminant capture in a ventilation system can be realized by using

• A.

An air cleaner.

• B.

Higher velocities.

• C.

Elbows in the ducting

• D.

A flange or tapered hood.

D. A flange or tapered hood.
Explanation
A flange or tapered hood can help in reducing resistance and improving contaminant capture in a ventilation system. The flange or tapered hood design allows for smoother airflow and reduces turbulence, which in turn decreases resistance in the system. Additionally, the design of the flange or tapered hood helps to direct and capture contaminants more effectively, improving the overall performance of the ventilation system.

Rate this question:

• 4.

### How can friction losses in a ventilation system be reduced?

• A.

Decrease the hood size.

• B.

Increase the duct length.

• C.

Increase the duct velocity.

• D.

Increase the duct diameter.

D. Increase the duct diameter.
Explanation
Increasing the duct diameter can reduce friction losses in a ventilation system. This is because a larger diameter allows for smoother airflow, reducing the resistance caused by friction between the air and the duct walls. This results in improved airflow efficiency and reduced energy consumption.

Rate this question:

• 5.

### A density factor of one means that the air you are dealing with is at

• A.

A high altitude.

• B.

Elevated temperature.

• C.

High barometric pressure.

• D.

Standard temperature and pressure conditions.

D. Standard temperature and pressure conditions.
Explanation
A density factor of one indicates that the air is at standard temperature and pressure conditions. This means that the air is at a temperature of 0 degrees Celsius and a pressure of 1 atmosphere. Standard temperature and pressure conditions are used as a reference point for comparing and measuring the properties of gases.

Rate this question:

• 6.

### Which type of velocity refers to the speed of air at a point in front of a hood that is needed to pull contaminants into the hood?

• A.

Face velocity.

• B.

Duct velocity.

• C.

Capture velocity.

• D.

Transport velocity.

C. Capture velocity.
Explanation
Capture velocity refers to the speed of air at a point in front of a hood that is needed to pull contaminants into the hood. It is the velocity required to overcome the opposing forces (such as gravity and air currents) and ensure that the contaminants are effectively captured and drawn into the hood.

Rate this question:

• 7.

### What are two parameters at a given point in ventilation systems that are needed to calculate the air flow volume?

• A.

Area and pressure.

• B.

Area and velocity.

• C.

Velocity and pressure.

• D.

Diameter and velocity.

B. Area and velocity.
Explanation
To calculate the air flow volume in ventilation systems, two parameters needed are the area of the opening through which the air flows and the velocity of the air. The area represents the size of the opening, while the velocity represents the speed at which the air is moving through that opening. By multiplying the area and velocity together, the air flow volume can be determined.

Rate this question:

• 8.

### Areas of ducts and hoods must be expressed in

• A.

Inches.

• B.

Linear feet.

• C.

Square feet.

• D.

Cubic feet per minute.

C. Square feet.
Explanation
The areas of ducts and hoods must be expressed in square feet because square feet is a unit of measurement for two-dimensional surfaces. Ducts and hoods are typically flat or have a specific cross-sectional shape, so their areas can be measured in square feet. This measurement is important for determining the size and capacity of ducts and hoods in various applications, such as ventilation systems or kitchen exhaust systems. Inches, linear feet, and cubic feet per minute are not appropriate units for expressing the area of ducts and hoods.

Rate this question:

• 9.

### What circumstance would result in a high K factor?

• A.

• B.

Higher contaminant toxicities.

• C.

An even evolution of contaminant.

• D.

A high occupational exposure limit.

B. Higher contaminant toxicities.
Explanation
A high K factor refers to a high contaminant toxicity, meaning that the contaminant being released into the air is highly toxic. This toxic contaminant can have a significant impact on the health and safety of individuals in the surrounding environment, making it crucial to take appropriate measures to control and mitigate its effects.

Rate this question:

• 10.

### What is the maximum amount of a certain chemical vapor that air can hold at a given temperature?

• A.

Vapor pressure.

• B.

Explosive limit.

• C.

Saturation concentration

• D.

Required air flow volume.

C. Saturation concentration
Explanation
Saturation concentration refers to the maximum amount of a certain chemical vapor that air can hold at a given temperature. It is the point at which the air is fully saturated and can no longer hold any more vapor. This is determined by factors such as temperature, pressure, and the properties of the specific chemical.

Rate this question:

• 11.

### A minimum K factor of four is used in dilution ventilation for fire and explosion control because

• A.

Very toxic chemicals are involved.

• B.

Good air distribution cannot be achieved.

• C.

Concentrations must be kept at or below 25% of the lower explosive limit (LEL).

• D.

Concentrations must be kept at or below 25% of the upper explosive limit(UEL).

C. Concentrations must be kept at or below 25% of the lower explosive limit (LEL).
Explanation
A minimum K factor of four is used in dilution ventilation for fire and explosion control because concentrations must be kept at or below 25% of the lower explosive limit (LEL). This means that the ventilation system needs to dilute the concentration of flammable gases or vapors in the air to a safe level to prevent explosions. A K factor of four ensures that the concentration is reduced to a level that is below 25% of the LEL, minimizing the risk of fire or explosion.

Rate this question:

• 12.

### Other than good contaminant control, what is the biggest advantage of local exhaust over dilution ventilation?

• A.

Less noise.

• B.

Lower operating costs.

• C.

Better protection for equipment.

• D.

B. Lower operating costs.
Explanation
The biggest advantage of local exhaust over dilution ventilation is lower operating costs. Local exhaust systems are designed to capture and remove contaminants at the source, which reduces the need for large amounts of ventilation air. This results in lower energy consumption and operating costs compared to dilution ventilation, which requires a higher volume of air to dilute and remove contaminants.

Rate this question:

• 13.

### Two major advantages of local exhaust enclosures are that they provide

• A.

Better protection for the equipment and less noise.

• B.

The best contaminant control with the lowest air volume.

• C.

Better air distribution with the elimination of disturbances.

• D.

B. The best contaminant control with the lowest air volume.
Explanation
Local exhaust enclosures provide the best contaminant control with the lowest air volume. This means that they are effective in capturing and removing contaminants from the air in a specific area, while minimizing the amount of air that needs to be treated. By controlling and reducing the amount of air volume required, local exhaust enclosures can be more efficient and cost-effective compared to other options. This advantage makes them a preferred choice for industries and processes that generate airborne contaminants that need to be controlled and removed.

Rate this question:

• 14.

### The purpose of using splitter vanes, multiple takeoffs, or baffles inside of a local exhaust hood is to provide

• A.

A reduction in system resistance.

• B.

An increase in hood static pressure.

• C.

Proper discharge of air away from inlets.

• D.

Uniform air distribution across the hood face.

D. Uniform air distribution across the hood face.
Explanation
Splitters vanes, multiple takeoffs, or baffles inside of a local exhaust hood are used to ensure that the air is evenly distributed across the hood face. This is important because it helps to capture and remove contaminants effectively. By achieving uniform air distribution, the hood can effectively capture the contaminants at their source, preventing them from escaping into the surrounding environment.

Rate this question:

• 15.

### Increasing the velocity of air through a slot hood without increasing the air flow volume most often results in

• A.

An increase in contaminant control.

• B.

A decrease in contaminant control.

• C.

An increase in system resistance.

• D.

A decrease in system resistance.

C. An increase in system resistance.
Explanation
Increasing the velocity of air through a slot hood without increasing the air flow volume will result in an increase in system resistance. This is because increasing the air velocity without increasing the air flow volume means that the same amount of air is being forced through a smaller area, leading to increased pressure and resistance within the system. This can make it more difficult for the air to flow through the system and can potentially decrease the effectiveness of contaminant control.

Rate this question:

• 16.

### What type of ventilation system survey would Bioenvironmental Engineering (BE) perform on a new ventilation system to verify it is operating properly before putting it into service?

• A.

Routine survey.

• B.

Baseline survey.

• C.

Initial acceptance survey

• D.

Contaminant source survey.

C. Initial acceptance survey
Explanation
Bioenvironmental Engineering (BE) would perform an initial acceptance survey on a new ventilation system to verify it is operating properly before putting it into service. This type of survey is conducted to ensure that the system meets all the necessary requirements and standards for operation and that there are no issues or malfunctions that could potentially impact the health and safety of individuals using the system. It is an essential step in the process of implementing a new ventilation system to ensure its effectiveness and efficiency.

Rate this question:

• 17.

### In a routine survey, ventilation system data collected during the routine assessment should be compared to

• A.

Key parameters.

• B.

Factory findings.

• C.

Previous routine survey data.

• D.

Data collected during the baseline survey.

D. Data collected during the baseline survey.
Explanation
In a routine survey, the ventilation system data collected should be compared to the data collected during the baseline survey. This is because the baseline survey provides the initial measurements and conditions of the ventilation system, which serves as a reference point for future assessments. By comparing the current data to the baseline data, any changes or deviations can be identified and evaluated. Comparing the data to key parameters, factory findings, or previous routine survey data may not provide an accurate assessment of the ventilation system's performance over time.

Rate this question:

• 18.

### When performing face velocity measurements, what must you do just before measuring the air flow of a ventilation system?

• A.

Calibrate the survey meter.

• B.

Take static pressure measurements.

• C.

Identify the key parameter for the system.

• D.

Measure out or mentally form a grid over the duct opening.

D. Measure out or mentally form a grid over the duct opening.
Explanation
Before measuring the air flow of a ventilation system, it is necessary to measure out or mentally form a grid over the duct opening. This is important because it helps to ensure that the measurements are taken at consistent and accurate points across the opening. By creating a grid, it becomes easier to systematically measure the face velocity at various points, which provides a more comprehensive understanding of the air flow in the system. This step helps to ensure reliable and consistent measurements during the face velocity measurements.

Rate this question:

• 19.

### What important procedure must you follow to obtain accurate readings with a velometer?

• A.

Hold the probe parallel to the air flow.

• B.

Always make two traverses at right angles to one another.

• C.

Choose a section of the duct with smooth flow for measurement.

• D.

Hold tube so that the mark aligns with the side of the duct and point tube directly into the air stream.

A. Hold the probe parallel to the air flow.
Explanation
To obtain accurate readings with a velometer, it is important to hold the probe parallel to the air flow. This ensures that the measurement is taken in the direction of the air flow, allowing for accurate velocity readings. Holding the probe at an angle could result in incorrect measurements as it may not capture the full force of the air flow. Therefore, aligning the probe parallel to the air flow is crucial for obtaining accurate readings with a velometer.

Rate this question:

• 20.

### What may be indicated by a very strong flow coming in an open door of a room containing a local exhaust system?

• A.

• B.

Excessive cross drafts.

• C.

• D.

Proper discharge of air away from inlets.

Explanation
A very strong flow coming in an open door of a room containing a local exhaust system may indicate inadequate makeup air. This means that the exhaust system is pulling in more air from outside the room than is being supplied, causing a negative pressure inside the room. As a result, air is being drawn in through any available openings, such as the open door, to balance the pressure. This indicates that the room is not receiving enough fresh air to compensate for the air being exhausted, leading to inadequate makeup air.

Rate this question:

• 21.

### What is the purpose of the inner tube that makes up a pitot tube?

• A.

Detect total pressure.

• B.

Detect static pressure.

• C.

Determine the duct diameter.

• D.

Determine the density factor.

A. Detect total pressure.
Explanation
The purpose of the inner tube in a pitot tube is to detect the total pressure of the fluid flow. The total pressure is the sum of the static pressure (pressure exerted by the fluid due to its motion) and the dynamic pressure (pressure exerted by the fluid due to its velocity). By measuring the total pressure, the pitot tube can provide information about the velocity and energy of the fluid flow.

Rate this question:

• 22.

### What can be said of velocity pressure when measured across the duct?

• A.

It is constant across the duct.

• B.

It is weak along the sides and becomes weaker as you near the center.

• C.

It is weaker along the sides and becomes stronger as you near the center.

• D.

It is stronger along the sides and becomes weaker as you near the center.

C. It is weaker along the sides and becomes stronger as you near the center.
Explanation
Velocity pressure refers to the pressure exerted by a fluid due to its velocity. In the case of a duct, the velocity of the fluid is highest at the center and decreases towards the sides. Therefore, the velocity pressure is weaker along the sides and becomes stronger as you near the center.

Rate this question:

• 23.

### When evaluating ventilation systems using the pitot traverse method, what step is performed after balancing the system?

• A.

Prepare the equipment for use.

• B.

Find a suitable measurement point.

• C.

Take velocity pressure measurements.

• D.

Identify the key parameter for the system.

C. Take velocity pressure measurements.
Explanation
After balancing the system, the next step in evaluating ventilation systems using the pitot traverse method is to take velocity pressure measurements. This involves using a pitot tube to measure the velocity pressure at various points in the system to determine the airflow velocity. These measurements are essential in determining the effectiveness and efficiency of the ventilation system.

Rate this question:

• 24.

### The range of acceptable values for the air flow volume on routine tests is within what percentage of the baseline value?

• A.

25%.

• B.

20%.

• C.

15%.

• D.

10%.

D. 10%.
Explanation
The range of acceptable values for the air flow volume on routine tests is within 10% of the baseline value. This means that the air flow volume can deviate by up to 10% from the baseline value and still be considered acceptable.

Rate this question:

• 25.

### Two sources of indoor air contamination are interior air and

• A.

Volatile organic compounds (VOC).

• B.

Exterior air.

• C.

• D.

Combustion contaminants.

B. Exterior air.
Explanation
Exterior air is one of the sources of indoor air contamination. This means that pollutants from the outdoor environment can enter indoor spaces and contribute to poor air quality. These pollutants can include dust, pollen, smoke, and other harmful particles. It is important to have proper ventilation and filtration systems in place to minimize the impact of exterior air on indoor air quality.

Rate this question:

• 26.

### What are the two most important factors to any indoor air quality (IAQ) survey?

• A.

Education and training.

• B.

Education and counseling.

• C.

Communication and education.

• D.

Communication and counseling.

C. Communication and education.
Explanation
The two most important factors to any indoor air quality (IAQ) survey are communication and education. Effective communication is crucial for gathering accurate information and understanding the concerns and needs of the individuals involved. It helps in establishing trust and creating a comfortable environment for sharing information. Education is important to ensure that everyone involved understands the importance of IAQ, the potential risks, and the necessary steps to improve it. It helps in promoting awareness and empowering individuals to make informed decisions regarding IAQ.

Rate this question:

• 27.

### Who interviews the workplace supervisor and enrolled individual when investigating an abnormal exposure to determine its cause?

• A.

MAJCOM Bioenvironmental Engineering (BE) and base BE.

• B.

• C.

Installation Radiation Safety Officer (IRSO) and BE.

• D.

Base Ground Safety and workplace supervisor.

C. Installation Radiation Safety Officer (IRSO) and BE.
Explanation
The Installation Radiation Safety Officer (IRSO) and BE (Bioenvironmental Engineering) would be responsible for conducting an investigation into an abnormal exposure to determine its cause. They would interview both the workplace supervisor and the enrolled individual to gather information and gather evidence to identify the cause of the exposure. The IRSO would specifically focus on radiation safety concerns, while BE would have expertise in investigating and assessing environmental factors that may have contributed to the exposure.

Rate this question:

• 28.

### If any abnormal or potential overexposure occurs, the Installation Radiation Safety Officer (IRSO) must notify what person/agency?

• A.

Air Force Medical Support Agency (AFMSA/SG3PB).

• B.

Aerospace Medicine Council.

• C.

• D.

Base Ground Safety.

A. Air Force Medical Support Agency (AFMSA/SG3PB).
Explanation
The correct answer is the Air Force Medical Support Agency (AFMSA/SG3PB). The Installation Radiation Safety Officer (IRSO) is responsible for ensuring radiation safety at the installation. If any abnormal or potential overexposure occurs, the IRSO must notify the AFMSA/SG3PB, which is the agency responsible for providing medical support and guidance to the Air Force. They have the expertise and resources to assess and manage any radiation-related health concerns that may arise.

Rate this question:

• 29.

### When radiation exposures to the head and lens of the eye must be evaluated, what is the primary device used to evaluate exposure?

• A.

Collar.

• B.

Neutron.

• C.

Extremity.

• D.

Whole body.

A. Collar.
Explanation
The primary device used to evaluate radiation exposures to the head and lens of the eye is a collar. A collar is a protective device worn around the neck that measures the radiation dose received in that area. It is specifically designed to protect the thyroid gland and the lens of the eye, which are particularly sensitive to radiation. By using a collar, the exposure to these critical organs can be accurately evaluated and appropriate measures can be taken to minimize the risk of radiation damage.

Rate this question:

• 30.

### If a work area being monitored by the USAF Personnel Dosimetry Program requires five whole body badges, five collar badges, and five finger badges each monitoring period, how many control badges does it require??

• A.

15.

• B.

5

• C.

3

• D.

1

C. 3
Explanation

Rate this question:

• 31.

### When is monitoring required for certain radiation workers?

• A.

Pregnant workers likely to exceed 50 millirem (mrem) during gestation.

• B.

Pregnant workers likely to exceed 100 mrem during pregnancy.

• C.

Workers likely to exceed 15% of the annual limits of intake.

• D.

Workers likely to exceed 10% of the annual external dose limit.

D. Workers likely to exceed 10% of the annual external dose limit.
Explanation
Monitoring is required for certain radiation workers when they are likely to exceed 10% of the annual external dose limit. This means that if their exposure to radiation is expected to reach or exceed 10% of the maximum allowable dose for a year, they need to be monitored. This helps ensure that their radiation exposure is within safe limits and allows for appropriate measures to be taken if necessary to protect their health and safety.

Rate this question:

• 32.

### Prior to briefing the dosimeter wearer, completing the Listing 1523, and issuing the dosimeter, what must you do to enroll an individual in the dosimetry program?

• A.

Complete the listing 1499.

• B.

Establish the exposure history.

• C.

Obtain medical examination findings.

• D.

Coordinate with the Base Safety Office.

B. Establish the exposure history.
Explanation
To enroll an individual in the dosimetry program, it is necessary to establish their exposure history. This involves gathering information about their past exposure to radiation, such as previous job roles or activities that may have exposed them to radiation. By understanding their exposure history, the dosimetry program can accurately assess and monitor their radiation dose levels to ensure their safety.

Rate this question:

• 33.

### What factor necessitates a more frequent dosimeter exchange?

• A.

Pregnant workers with a potential to exceed 200 mrem during pregnancy.

• B.

Certain operations having radiation exposures greater than 1.25 rem per year.

• C.

Certain operations having radiation exposures greater than 1.50 rem per month.

• D.

Prior exposure history of individual beginning work as an occupational radiation worker.

D. Prior exposure history of individual beginning work as an occupational radiation worker.
Explanation
Workers who have a prior exposure history of working with radiation would require a more frequent dosimeter exchange. This is because their previous exposure history indicates that they may have a higher risk of radiation exposure in their current occupation. By exchanging the dosimeter more frequently, it allows for more accurate monitoring of their radiation exposure levels and ensures that they are not exceeding the recommended limits.

Rate this question:

• 34.

### Once dosimeters are collected after the monitoring period and disassembled, what two things must be compared to account for all issued dosimeters?

• A.

TLD number and the Listing 1523.

• B.

Shipping document and TLD number.

• C.

TLD shipping holder and TLD number.

• D.

Listing 1499 and shipping document.

A. TLD number and the Listing 1523.
Explanation
The TLD number and the Listing 1523 must be compared to account for all issued dosimeters. This is because the TLD number is a unique identifier for each dosimeter and the Listing 1523 is a record that lists all the dosimeters that were issued. By comparing the TLD number with the Listing 1523, it can be ensured that all the dosimeters that were issued have been accounted for.

Rate this question:

• 35.

### You must ship dosimeters within how many working days after the monitoring period ends?

• A.

2

• B.

5

• C.

15

• D.

30

B. 5
Explanation
According to the given question, the dosimeters must be shipped within a certain number of working days after the monitoring period ends. The correct answer is 5, which means that the dosimeters should be shipped within 5 working days after the monitoring period ends.

Rate this question:

• 36.

### What should the Installation Radiation Safety Officer (IRSO) develop for each dose equivalent category of the Listing 1499?

• A.

Maximum exposure rates.

• B.

ALARA training requirements.

• C.

Investigation actions levels.

• D.

Installation activity levels.

C. Investigation actions levels.
Explanation
The Installation Radiation Safety Officer (IRSO) should develop investigation action levels for each dose equivalent category of the Listing 1499. This means that the IRSO needs to establish specific levels at which further investigation and actions should be taken in response to certain dose equivalent levels. These levels will help in determining the appropriate steps to be taken in order to ensure radiation safety and minimize any potential risks or hazards.

Rate this question:

• 37.

### Which agency serves as the office of primary responsibility (OPR) for the installation respiratory protection program?

• A.

Civil Engineering (CE).

• B.

Bioenvironmental Engineering (BE).

• C.

USAF School of Aerospace Medicine (USAFSAM).

• D.

Occupational Safety and Health Administration (OSHA).

B. Bioenvironmental Engineering (BE).
Explanation
Bioenvironmental Engineering (BE) serves as the office of primary responsibility (OPR) for the installation respiratory protection program. This means that BE is responsible for overseeing and managing all aspects of the program, including developing policies and procedures, conducting training, and ensuring compliance with regulations. BE has the expertise and knowledge in environmental health and safety to effectively manage and implement the respiratory protection program at the installation.

Rate this question:

• 38.

### What document lists each of the workplaces that use respiratory protection?

• A.

Master Respirator Inventory.

• B.

Certified Respirator Inventory.

• C.

Respirator Protection Inventory.

• D.

Installation Respirator Inventory.

A. Master Respirator Inventory.
Explanation
The Master Respirator Inventory is a document that lists each of the workplaces that use respiratory protection. It serves as a comprehensive record of all the locations where respiratory protection is required, ensuring that all workplaces are accounted for and properly equipped with the necessary respiratory equipment. This inventory helps in managing and tracking the availability and distribution of respirators across different workplaces, ensuring the safety and well-being of the employees.

Rate this question:

• 39.

### What type of respirator is designed to filter a chemical out of the surrounding air?

• A.

Air-line.

• B.

Air-purifying.

• C.

Closed circuit SCBA.

• D.

Atmosphere supplying.

B. Air-purifying.
Explanation
An air-purifying respirator is designed to filter a chemical out of the surrounding air. This type of respirator uses filters or cartridges to remove contaminants from the air before it is inhaled by the wearer. It is commonly used in situations where the air is contaminated with harmful substances such as chemicals, gases, or particles. The filters or cartridges in an air-purifying respirator are specifically designed to trap and remove the particular type of contaminant present in the air.

Rate this question:

• 40.

• A.

N

• B.

P

• C.

R

• D.

S

A. N
• 41.

### What respirator remains dependent upon an air supply that is not carried by the wearer?

• A.

Air-line.

• B.

Air-purifying.

• C.

Open-circuit SCBA.

• D.

Closed-circuit SCBA.

A. Air-line.
Explanation
An air-line respirator remains dependent upon an air supply that is not carried by the wearer. This type of respirator is connected to an external air source through a hose or tube, providing a continuous supply of clean air to the wearer. Unlike air-purifying respirators that rely on filters to remove contaminants from the air or self-contained breathing apparatus (SCBA) that carry their own air supply, the air-line respirator requires a separate air source to function effectively.

Rate this question:

• 42.

### Which respirator is designed to capture and scrub the exhaled air of carbon dioxide?

• A.

Air-line.

• B.

Air-purifying.

• C.

Open-circuit self-contained breathing apparatus (SCBA).

• D.

Closed-circuit SCBA.

D. Closed-circuit SCBA.
Explanation
A closed-circuit SCBA is designed to capture and scrub the exhaled air of carbon dioxide. Unlike other respirators, which release the exhaled air into the environment, a closed-circuit SCBA recirculates the exhaled air back to the user after removing carbon dioxide through a scrubbing process. This ensures that the user breathes in clean air without the build-up of carbon dioxide, making it an effective choice for environments with high levels of carbon dioxide or where air quality needs to be closely controlled.

Rate this question:

• 43.

### At a minimum, respirators used for emergency use only are required to be inspected

• A.

Monthly.

• B.

Quarterly.

• C.

Annually.

• D.

Bi-annually.

A. Monthly.
Explanation
Respirators used for emergency use only are required to be inspected at a minimum of once a month. This frequency ensures that the respirators are in proper working condition and ready for use during emergencies. Regular inspections help identify any potential issues or damage that may affect the effectiveness of the respirators. By inspecting the respirators monthly, any necessary repairs or replacements can be made promptly, ensuring the safety of the users.

Rate this question:

• 44.

### Who shoulders the responsibility for respirator use in their work area?

• A.

Safety manager.

• B.

Individual user.

• C.

Shift supervisor.

• D.

Workplace supervisor.

D. Workplace supervisor.
Explanation
The workplace supervisor shoulders the responsibility for respirator use in their work area. They are responsible for ensuring that proper safety measures are in place, including providing and maintaining respirators, training employees on their proper use, and enforcing their use in the work area. The safety manager may have a role in overseeing overall safety protocols, but the immediate responsibility for respirator use lies with the workplace supervisor. The individual user and shift supervisor may have some responsibility in using and enforcing the use of respirators, but the ultimate responsibility lies with the workplace supervisor.

Rate this question:

• 45.

### Selecting respiratory protection equipment starts with what?

• A.

Calculating the hazard ratio for each contaminant involved.

• B.

Identifying existing engineering and administrative controls.

• C.

Identifying work center respiratory hazards that may be present.

• D.

Performing a hazard determination of the contaminant(s) involved.

C. Identifying work center respiratory hazards that may be present.
Explanation
Selecting respiratory protection equipment starts with identifying work center respiratory hazards that may be present. This is because it is important to first determine the hazards that workers may be exposed to in order to select the appropriate respiratory protection equipment. Once the hazards are identified, a hazard determination can be performed to assess the level of risk and determine the type of respiratory protection needed. Calculating the hazard ratio, identifying existing controls, and performing a hazard determination are all important steps in the process, but they come after identifying the respiratory hazards.

Rate this question:

• 46.

### Which of the following might affect the service life of a respirator?

• A.

Exposure route.

• B.

Extreme physical exertion.

• C.

Immediately dangerous to life or health conditions.

• D.

Whether the worker is in the hazardous area continuously or intermittently during the shift.

B. Extreme physical exertion.
Explanation
Extreme physical exertion can affect the service life of a respirator because it can cause the wearer to breathe more heavily and increase the demand for air. This increased breathing rate can lead to a faster depletion of the respirator's filtering capacity and reduce its effectiveness in filtering out contaminants. Additionally, physical exertion can cause sweating, which can affect the fit of the respirator and compromise its seal, allowing contaminants to enter.

Rate this question:

• 47.

### What is the highest contaminant concentration for which a respirator adequately protects the wearer?

• A.

Fit factor.

• B.

Hazard ratio.

• C.

Maximum use concentration.

• D.

Assigned protection factor.

C. Maximum use concentration.
Explanation
The highest contaminant concentration for which a respirator adequately protects the wearer is referred to as the maximum use concentration. This indicates the maximum level of a hazardous substance that a respirator can effectively filter out, ensuring the wearer's safety. The maximum use concentration is determined through extensive testing and evaluation of the respirator's performance and efficiency.

Rate this question:

• 48.

### During which step of the respirator selection process do you measure the concentration of the contaminant, and determine if it is equal to or greater than 10 percent of the lower explosive limit, if the potential for an explosive atmosphere exists?

• A.

Performing a hazard determination.

• B.

Calculating the maximum use concentration.

• C.

Calculating the hazard ratio for each contaminant involved.

• D.

Identifying work center respiratory hazards that may be present.

A. Performing a hazard determination.
Explanation
Performing a hazard determination is the step in the respirator selection process where you measure the concentration of the contaminant and determine if it is equal to or greater than 10 percent of the lower explosive limit. This is important when there is a potential for an explosive atmosphere, as it helps to assess the level of risk and determine the appropriate respirator to use in such conditions.

Rate this question:

• 49.

### Fit testing is the only practical way to ensure a barrier is formed between a worker’s respiratory system and the harmful agent. Which refers to the measurement of the integrity of this barrier?

• A.

Fit factor.

• B.

Comfort variable.

• C.

IDLH concentration.

• D.

Maximum use concentration.

A. Fit factor.
Explanation
Fit factor refers to the measurement of the integrity of the barrier formed between a worker's respiratory system and the harmful agent. It is the only practical way to ensure that the barrier is effective in protecting the worker from the harmful agent. Comfort variable, IDLH concentration, and maximum use concentration are not related to the measurement of the barrier's integrity.

Rate this question:

• 50.

### What actions should be taken if a respirator quantitative fit-test (QNFT) sequence fails a second time?

• A.

Repeat the test on a replacement mask of the same size.

• B.

Size down one size and repeat the fitting and fit-testing procedures.

• C.

Repeat the test on the same mask.

• D.

Size up one size and repeat the fitting and fit-testing procedures.

A. Repeat the test on a replacement mask of the same size.
Explanation
If a respirator quantitative fit-test (QNFT) sequence fails a second time, the recommended action is to repeat the test on a replacement mask of the same size. This suggests that the issue may not be with the mask itself but with the fit or seal of the mask on the individual's face. By using a replacement mask of the same size, it allows for the possibility of a better fit and a successful fit-test result.

Rate this question:

Related Topics