1. Calculate WGBT and make recommendations on work – rest schedule:
Q: On a sunny warm day (27 degrees C wet bulb, 30 degrees C globe and 29 degrees C air temp) how would work load affect required controls for heat stress?

A: WBGTout = 0.7(WB) + 0.2(g) + 0.1(d) = (0.7 x 27) + (0.2 x 30) + (0.1 x 29) = 27.8
There for: At 27.8 WBGTout the dose of work would equal * Light work @ 100 % * Moderate work @ 100 % * High work @ 25 – 50 % work rest

2. In measuring noise exposure, you have identified several different sources of noise. They produce the following sound pressure levels: 92dB, 90dB, 85dB and 87dB. What is the combined sound pressure level of the four sources of noise?
A: ** Start from highest to lowest **
92dB – 90dB = 2 therefor 92 + 2 = 94 therefor 94 – 87 = 7 therefor 94 + 1 = 95 there for 95 – 85 = 10 therefor 95 + 0 ** because all values have been used the answer is 95.
NOTE: numbers in bold and italicised writing are found on adding decibel chart

3. An employee had the following exposures in an 8 hour shift. Are they over exposed? 1hr @ 80dBA 4hrs @ 85dBA 2hrs @ 88dBA 1hr @ 91dBA

A: ** First of all 80dBA does not have an exposure level so do not use it **
Dose = (4hrs/ 8hrs + 2hrs/ 4hrs + 1hr/ 2hrs) X 100 = 150% therefor YES the worker is over exposed these numbers are found from OHS code schedule 3 Noise if under 100 % the worker is not exposed, if over 100 % the worker is exposed

4. a) Local Exhaust Ventilation: Designed to capture the contaminant stream as close to the source as possible while minimizing the amount of air exhausted b) Dilution Ventilation: Introduces uncontaminated air into the workplace to dilute contaminants being generated
Advantages of Local Exhaust Ventilation: The contaminant is not allowed to enter the workplace air, a minimal amount of air is exhausted and needed to be made up, it can be useful for contaminants having a high toxicity, and it can also be used for non-uniform release of contaminants.
Advantages of Dilution Ventilation: Useful when there are many contaminant generation points, the design of dilution ventilation systems are relatively simple, do not require elaborate system ducts.

5. Respirator Fit Test:
- Qualitative: Involves the introduction of a known substance (test agent) around the head of the respirator wearer. It relies on the subject response of the wearer. Tests are fast and usually performed in the field. (resp goes on, irritant released, worker moves head up and down, if the wearer detects irritant there is a leak)
- Quantitative: Measures the level of particulate inside the respirator and compares to the level outside the respirator. Does not rely on objective responses by the wearer.

6. Respirator Protection Factors PF = Concentration outside of face Concentration inside of face * Often specified by regulators, when selecting respirators the following should be true
Airborne concentration LESS THAN (<) OEL PF of respirator
Eg. Xelyne has OEL of 100ppm and an airborne concentration of 500ppm has been measured. A respirator with what protection factor is required to ensure the wearer is breathing below the OEL?
PF > 500ppm / 100ppm > 5
Disposable / low maintenance = 5 or less
Half mask = 10
Full face = 50
PARP with HEPA filter = 100
Full face airline pressure demand = 1000
Positive pressure SCBA = 10,000
7. What are some ways to improve air quality?
- Take all complaints serious
- Review patterns and other information – formulate a hypothesis which may explain the problem
- repeat the process
- Use flow charts, assess complaint, HVAC info
- take samples and measure or evaluate

8. How long does it take people to acclimatize? 5 days

9. What are the steps to developing an IAQ profile? - Collect and review existing records - Conduct a walk through inspection of the building (investigate using your 4 sense) - Collect detailed info
10. What causes sensory – neural hearing loss?
Frequencies between 20HZ and 20,000HZ over a long period of time

11. What are three ways to control exposure?
Engineering, Admin, PPE

12. What does L.A.S.E.R stand for?
Light Amplification by Stimulated Emission of Radiation

13. What is the difference between ionizing and non-ionizing radiation?
Ionizing radiation is higher energy and is capable of ionizing atoms that make up our bodies. Non-ionizing radiation is lower energy and although capable of some negative health effects cannot cause ionization.

Highest =Alpha, beta, gamma, neutron, UV and visible infrared, microwaves, radio wave and TV = Lowest

14. What is the most serious cold illness: Hypothermia

15. Heat stress environmental factors are: - Dry bulb temp: air temp - Wet bulb temp: produces and indication of relative humidity - Relative humidity - Ventilation, airflow and wind - Globe temperature - Clothing / PPE
16. What is the most common indoor air quality concern? Odors

17. What are the main components of local exhaust ventilation system (LEV) - Stack: the outlet or exhaust point where the air is released from the system - Exhaust Fan: Provides the necessary movement of air through the system - Air cleaner: Removes the contaminant from the air before it is released to the environment - Air duct: carries the contaminated air from the work area through the system to the exhaust 1111111rack - Exhaust Hood: captures and draws the contaminant into the system

18. What height level should you work at for precision work? Chest Height

19. What are some benefits of ergonomics? - Reduced fatigue and stress - increased comfort and safety - Increased job satisfaction - Increased productivity and quality - Reduced # of injuries

20. What is the WBGT Index? - Takes into account air temp, humidity, radiant heat and air movement - Air temp is measured using dry bulb thermometer - Black globe absorbs heat and measures radiant heat - Wet bulb measures evaporation and air movement

21. How can HVAC systems create contaminant issues?
HVAC systems have a significant impact on condensation, a source of moisture for mold. The system can also transport mold spores between areas of a building. Poor design, operation and maintenance of the system also can provide moisture to support mold growth, and the system can provide a viable transportation mode for mold spores throughout a building.