CESCO Industrial Hygiene & Exposure Monitoring 2 — Questions and Answers
Question 1: Under OSHA's Respiratory Protection standard (29 CFR 1910.134), a quantitative fit test uses which measurement to determine respirator fit?
- Fit factor — ratio of particle concentration outside to inside the facepiece (Correct answer)
- Qualitative pass/fail based on taste or odor detection
- CO2 concentration inside the mask
- Flow resistance measured in mm H2O
Correct answer: Fit factor — ratio of particle concentration outside to inside the facepiece
Quantitative fit testing measures the fit factor — the ratio of ambient challenge agent concentration outside the mask to concentration inside — using an instrument such as a PortaCount.
Question 2: Which class of respirator provides the highest level of respiratory protection and is suitable for IDLH atmospheres?
- Self-Contained Breathing Apparatus (SCBA) (Correct answer)
- Half-face air-purifying respirator
- Powered air-purifying respirator (PAPR)
- N95 filtering facepiece respirator
Correct answer: Self-Contained Breathing Apparatus (SCBA)
SCBA supplies clean air from a portable tank, providing full-face protection independent of the ambient atmosphere, making it required in IDLH conditions.
Question 3: Heat stress is evaluated using which composite index that accounts for temperature, humidity, and radiant heat?
- Wet Bulb Globe Temperature (WBGT) (Correct answer)
- Heat Index (HI)
- Apparent Temperature
- Discomfort Index (DI)
Correct answer: Wet Bulb Globe Temperature (WBGT)
WBGT combines natural wet bulb, globe (radiant heat), and dry bulb temperatures and is the internationally accepted standard for occupational heat stress assessment.
Question 4: Ergonomic hazards that can cause musculoskeletal disorders (MSDs) in the workplace include which of the following risk factors?
- Repetitive motion, awkward postures, and forceful exertions (Correct answer)
- Noise levels above 85 dBA
- Ionizing radiation exposure
- Chemical skin sensitizers
Correct answer: Repetitive motion, awkward postures, and forceful exertions
MSDs are primarily caused by ergonomic risk factors including repetition, awkward postures, forceful exertions, contact stress, vibration, and extreme temperatures.
Question 5: A chemical is classified as a 'skin sensitizer' under GHS. What does this mean for exposure assessment?
- Dermal exposure can cause an allergic reaction upon re-exposure even at low concentrations (Correct answer)
- The chemical causes immediate burns on contact
- The chemical is primarily an inhalation hazard
- The chemical has an established skin PEL that must be monitored
Correct answer: Dermal exposure can cause an allergic reaction upon re-exposure even at low concentrations
Skin sensitizers cause allergic contact dermatitis; once sensitized, a worker can react severely to even trace exposures, making skin contact prevention critical.
Question 6: Which regulation requires that workers potentially exposed to bloodborne pathogens receive hepatitis B vaccination at the employer's expense?
- OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030) (Correct answer)
- OSHA HazCom Standard (29 CFR 1910.1200)
- CDC Universal Precautions Guidelines
- NIOSH Hierarchy of Controls
Correct answer: OSHA Bloodborne Pathogens Standard (29 CFR 1910.1030)
29 CFR 1910.1030 requires employers to offer the hepatitis B vaccine series to all employees with occupational exposure to bloodborne pathogens at no cost to the employee.
CESCO Industrial Hygiene & Exposure Monitoring 2
Under OSHA's Respiratory Protection standard (29 CFR 1910.134), a quantitative fit test uses which measurement to determine respirator fit?