NEBOSH Diploma Unit B - Revision- Questions
Latest Update 2024-2025 Real Exam 150
Questions and 100% Verified Correct Answers
Already Graded A+ Verified by Professor
Comment on its value as a measure to control contaminants (dilution ventilation) -
CORRECT ANSWER: This method is only suitable where there is a relatively low
concentration of high WEL contaminant which is given off slowly. It is not suitable where
operators are in close contact with the source of contamination
Define 'Workplace exposure limit'. - CORRECT ANSWER: defined as "maximum
concentration of an airborne substance, averaged over a reference period, to which
employees may be exposed by inhalation".
Define anxiety and depressions - CORRECT ANSWER: Anxiety - "feeling of unease,
such as worry or fear that can be mild or severe" (NHS)
Depression is when you have feelings of extreme sadness, despair or inadequacy that
last for a long time.
Define the term ' relative humidity' - CORRECT ANSWER: Relative humidity is an
expression of the ratio of water vapour in air relative to the maximum concentration of
water vapour that would be required to saturate air at the given temperature
Define the WBGT heat stress index - CORRECT ANSWER: WBGT is a heat stress
index used to make a prediction of the heat stress on a worker carrying out a particular
rate of work.
WBGT is calculated from:
WBGT = 0.7 WB + 0.3 GT indoors
,or
WBGT = 0.7 WB + 0.2 GT + 0.1 DB outdoors
where:-
- WB is the wet build temperature
- GT is the globe thermometer temperature
- DB is the dry bulb temperature
The index value (WBGT) must be used in conjunction with empirical recommendations
(set out in ISO 7243) to indicate a level that is safe for most people who are physically
fit and in good health.
Different values are quoted to distinguish persons acclimatised or unacclimatised to
heat.
If conditions of exposure fluctuate, a time-weighted average exposure can be derived
and used
Define what the Equality Act 2010 means by a disabled person - CORRECT ANSWER:
a person is disabled if they have "a physical or mental impairment which has a
substantial and long-term adverse effect on their ability to carry out normal dat-to-day
activities".
Describe a test that can be used to detect genetic mutation - CORRECT ANSWER: The
most well known test is the Ames test.
This involves exposing the mutagen to a specific strain of bacteria that will not normally
grow in a histidine-deficient growth medium.
Mutagens will cause a mutation in the bacteria allowing them to grow in a histidine-free
medium
,Describe an example of a retrospective cohort study - CORRECT ANSWER: Asbestos
exposure and lung disease
2 populations are identified which differ only by the fact that one group has been
historically exposed to asbestos and the other has not.
Evidence of exposure is collected from health records.
Medical surveillance is then carried out to gather data about the prevalence of lung
disease in these 2 groups.
This is reinforced with other health data.
Statistical analysis is then carried out to see if a link between lung disease and historic
asbestos exposure can be proven to exist.
Describe how oxygen enters the bloodstream - CORRECT ANSWER: Inhaled air
passes through the nose or mouth, down the trachea, bronchi and bronchioles, into
alveoli.
Here, the very thin lining of alveoli and blood vessels flows oxygen to diffuse into the
bloodstream where it then diffuses into red blood cells and is bound to haemoglobin.
Carbon dioxide is excreted by the same process
Describe how the ear converts sound waves into nerve stimulation to the auditory
centre of the brain. - CORRECT ANSWER: The ear transmits nerve impulses to the
brain as a result of detecting and transmitting mechanical vibration through the outer
ear, the middle ear and the inner ear.
Describe measures that can be taken to reduce individual stress by improving work
relationships. - CORRECT ANSWER: Interpersonal skills training:-
Interpersonal skills involve the ability to communicate and build relationships with
others. Often called "people skills," they tend to incorporate both your innate personality
traits and how you've learned to handle certain social situations. Effective interpersonal
skills can help you during the job interview process and can have a positive impact on
your career advancement.
, Effective systems to deal with various types of interpersonal conflict
Describe the classification system for lasers based on relative hazard potential -
CORRECT ANSWER: The classification System for lasers-
- Class 1 is considered safe use reasonably foreseeable used
- Class 1M is similar to Class 1, but the beam is not safe if viewed with the aid of
magnifying optical instruments
- Class 1C is the contact application to skin, such as in cosmetic skin treatments
- Class 2 (for lasers emitting in the visible range) - low power devices - eye protection is
normally afforded by the aversion response and the blink reflex of the eye.
- Class 2M is similar to Class 2, but beam is not safe if viewed with the aid of magnifying
optical instruments
- Class 3R laser products limited to maximum output power of 5mW - these can
potentially cause eye injury
- Class 3B laser products limited to a maximum output power of 500mW - these are
considered hazardous to the eye, both directly and reflections.
- Class 4 high -powered devices (>500mW) - they are hazardous to eyes and skin and
can cause fires
Describe the condition vibration-induced white-finger - CORRECT ANSWER: In the
early, stages, vibration causes slight tingling and numbness in the fingers.
With further exposure, the tips of one or more fingers suffers blanching and with
continued exposure blanching will extend to the base of the finger.
Latest Update 2024-2025 Real Exam 150
Questions and 100% Verified Correct Answers
Already Graded A+ Verified by Professor
Comment on its value as a measure to control contaminants (dilution ventilation) -
CORRECT ANSWER: This method is only suitable where there is a relatively low
concentration of high WEL contaminant which is given off slowly. It is not suitable where
operators are in close contact with the source of contamination
Define 'Workplace exposure limit'. - CORRECT ANSWER: defined as "maximum
concentration of an airborne substance, averaged over a reference period, to which
employees may be exposed by inhalation".
Define anxiety and depressions - CORRECT ANSWER: Anxiety - "feeling of unease,
such as worry or fear that can be mild or severe" (NHS)
Depression is when you have feelings of extreme sadness, despair or inadequacy that
last for a long time.
Define the term ' relative humidity' - CORRECT ANSWER: Relative humidity is an
expression of the ratio of water vapour in air relative to the maximum concentration of
water vapour that would be required to saturate air at the given temperature
Define the WBGT heat stress index - CORRECT ANSWER: WBGT is a heat stress
index used to make a prediction of the heat stress on a worker carrying out a particular
rate of work.
WBGT is calculated from:
WBGT = 0.7 WB + 0.3 GT indoors
,or
WBGT = 0.7 WB + 0.2 GT + 0.1 DB outdoors
where:-
- WB is the wet build temperature
- GT is the globe thermometer temperature
- DB is the dry bulb temperature
The index value (WBGT) must be used in conjunction with empirical recommendations
(set out in ISO 7243) to indicate a level that is safe for most people who are physically
fit and in good health.
Different values are quoted to distinguish persons acclimatised or unacclimatised to
heat.
If conditions of exposure fluctuate, a time-weighted average exposure can be derived
and used
Define what the Equality Act 2010 means by a disabled person - CORRECT ANSWER:
a person is disabled if they have "a physical or mental impairment which has a
substantial and long-term adverse effect on their ability to carry out normal dat-to-day
activities".
Describe a test that can be used to detect genetic mutation - CORRECT ANSWER: The
most well known test is the Ames test.
This involves exposing the mutagen to a specific strain of bacteria that will not normally
grow in a histidine-deficient growth medium.
Mutagens will cause a mutation in the bacteria allowing them to grow in a histidine-free
medium
,Describe an example of a retrospective cohort study - CORRECT ANSWER: Asbestos
exposure and lung disease
2 populations are identified which differ only by the fact that one group has been
historically exposed to asbestos and the other has not.
Evidence of exposure is collected from health records.
Medical surveillance is then carried out to gather data about the prevalence of lung
disease in these 2 groups.
This is reinforced with other health data.
Statistical analysis is then carried out to see if a link between lung disease and historic
asbestos exposure can be proven to exist.
Describe how oxygen enters the bloodstream - CORRECT ANSWER: Inhaled air
passes through the nose or mouth, down the trachea, bronchi and bronchioles, into
alveoli.
Here, the very thin lining of alveoli and blood vessels flows oxygen to diffuse into the
bloodstream where it then diffuses into red blood cells and is bound to haemoglobin.
Carbon dioxide is excreted by the same process
Describe how the ear converts sound waves into nerve stimulation to the auditory
centre of the brain. - CORRECT ANSWER: The ear transmits nerve impulses to the
brain as a result of detecting and transmitting mechanical vibration through the outer
ear, the middle ear and the inner ear.
Describe measures that can be taken to reduce individual stress by improving work
relationships. - CORRECT ANSWER: Interpersonal skills training:-
Interpersonal skills involve the ability to communicate and build relationships with
others. Often called "people skills," they tend to incorporate both your innate personality
traits and how you've learned to handle certain social situations. Effective interpersonal
skills can help you during the job interview process and can have a positive impact on
your career advancement.
, Effective systems to deal with various types of interpersonal conflict
Describe the classification system for lasers based on relative hazard potential -
CORRECT ANSWER: The classification System for lasers-
- Class 1 is considered safe use reasonably foreseeable used
- Class 1M is similar to Class 1, but the beam is not safe if viewed with the aid of
magnifying optical instruments
- Class 1C is the contact application to skin, such as in cosmetic skin treatments
- Class 2 (for lasers emitting in the visible range) - low power devices - eye protection is
normally afforded by the aversion response and the blink reflex of the eye.
- Class 2M is similar to Class 2, but beam is not safe if viewed with the aid of magnifying
optical instruments
- Class 3R laser products limited to maximum output power of 5mW - these can
potentially cause eye injury
- Class 3B laser products limited to a maximum output power of 500mW - these are
considered hazardous to the eye, both directly and reflections.
- Class 4 high -powered devices (>500mW) - they are hazardous to eyes and skin and
can cause fires
Describe the condition vibration-induced white-finger - CORRECT ANSWER: In the
early, stages, vibration causes slight tingling and numbness in the fingers.
With further exposure, the tips of one or more fingers suffers blanching and with
continued exposure blanching will extend to the base of the finger.
