CWEA Laboratory Analyst Grade 4 Exam:
100 Practice Questions and Explanations
Part One: Laboratory Safety and Hazard
Communication (1–15)
1. Which piece of personal protective equipment (PPE) is essential when handling
corrosive chemicals in the laboratory?
A. Safety glasses only
B. Nitrile gloves and safety goggles
C. Cotton lab coat only
D. Steel-toed boots
:B
Explanation: When handling corrosive chemicals, chemical-resistant gloves and safety
goggles or a face shield are essential to protect against splashes and burns. Safety glasses
alone do not provide sufficient splash protection .
2. What information is found on a Safety Data Sheet (SDS)?
A. Only the chemical name and formula
B. Physical and chemical properties, health hazards, first aid measures, and handling
precautions
C. The purchase price of the chemical
D. The name of the manufacturer only
:B
Explanation: An SDS provides comprehensive information about a chemical substance,
including physical and chemical properties, health hazards, first aid measures, handling and
storage precautions, exposure controls, and disposal considerations .
3. What is the primary purpose of a fume hood in the laboratory?
A. To provide additional storage space
B. To contain and exhaust hazardous vapors, gases, and fumes away from the analyst
C. To keep samples at a constant temperature
D. To prevent contamination of reagents
:B
Explanation: Fume hoods are engineering controls designed to protect laboratory personnel
by containing and exhausting hazardous airborne contaminants. They are essential when
working with volatile or toxic chemicals .
4. Which of the following is an example of an engineering control for laboratory safety?
A. Wearing safety goggles
,B. Using a fume hood
C. Reading the SDS
D. Following standard operating procedures
:B
Explanation: Engineering controls are physical modifications to the workplace that reduce
hazards. A fume hood is an engineering control. Safety goggles are PPE. Reading the SDS and
following SOPs are administrative controls .
5. What does the acronym "SDS" stand for in laboratory safety?
A. Standard Data Sheet
B. Safety Data Sheet
C. Sample Data Sheet
D. Standard Deviation Sheet
:B
Explanation: SDS stands for Safety Data Sheet, formerly known as Material Safety Data Sheet
(MSDS). It is a standardized document required by OSHA's Hazard Communication Standard
that communicates the hazards of chemical products .
6. What is the appropriate first aid for a chemical splash to the eyes?
A. Rub the eyes gently
B. Flush eyes with water for at least 15 minutes
C. Apply eye drops
D. Cover the eyes with a bandage
:B
Explanation: Immediate and thorough flushing of the eyes with water for at least 15 minutes
is the recommended first aid for chemical eye splashes. This helps dilute and remove the
chemical before it causes permanent damage .
7. Which class of fire extinguisher is used for flammable liquids such as gasoline, oils, and
solvents?
A. Class A
B. Class B
C. Class C
D. Class K
:B
Explanation: Class B fire extinguishers are designed for flammable liquids and gases,
including gasoline, oils, solvents, and paints. Class A is for ordinary combustibles, Class C is
for electrical fires, and Class K is for cooking oils .
8. What is the correct order of actions in the event of a fire in the laboratory?
A. Use a fire extinguisher, call 911, evacuate
B. Evacuate, pull the alarm, call 911, use extinguisher only if safe
C. Run and hide
, D. Call your supervisor first
:B
Explanation: The priority in a fire emergency is life safety: evacuate and activate the alarm
immediately. If the fire is small and safe to approach, use an extinguisher, but only after
evacuation and alarm activation .
9. According to Cal/OSHA requirements for a Grade 4 Laboratory Director, what document
must be reviewed and updated annually to ensure compliance with hazardous chemical
exposures in the workplace?
A. The Standard Operating Procedure (SOP) manual
B. The Chemical Hygiene Plan (CHP)
C. The Safety Data Sheet (SDS) inventory binder
D. The Emergency Action and Fire Evacuation Plan
:B
Explanation: Cal/OSHA requires that every laboratory utilizing hazardous chemicals maintain
and annually update a Chemical Hygiene Plan (CHP) specifically designed to protect workers
from physical and health hazards .
10. A laboratory analyst experiences chemical burns from a concentrated sulfuric acid spill.
Which administrative control must a Grade 4 Manager ensure was functioning to satisfy
immediate safety compliance?
A. Checking the expiration date on the employee's personal respirator
B. Verifying that the emergency eyewash and safety shower were inspected weekly and
provide tepid water
C. Reviewing the laboratory's liability insurance policy limits
D. Initiating an immediate formal reprimand file for the worker
:B
Explanation: Weekly verification and physical testing of safety showers and eyewash stations
are mandatory safety protocols under OSHA/Cal-OSHA to ensure mechanical reliability and
adequate water pressure in an emergency .
11. Hood flow should be monitored and documented at:
A. 50 linear feet per minute
B. 100 linear feet per minute
C. 150 linear feet per minute
D. 200 linear feet per minute
:B
Explanation: Hood flow should be monitored and documented at 100 linear feet per minute
to ensure adequate containment of hazardous vapors .
12. Standard phenylarsine oxide solution (PAO):
A. Is safe to handle without precautions
B. Should be handled with caution because it is a severe poison
100 Practice Questions and Explanations
Part One: Laboratory Safety and Hazard
Communication (1–15)
1. Which piece of personal protective equipment (PPE) is essential when handling
corrosive chemicals in the laboratory?
A. Safety glasses only
B. Nitrile gloves and safety goggles
C. Cotton lab coat only
D. Steel-toed boots
:B
Explanation: When handling corrosive chemicals, chemical-resistant gloves and safety
goggles or a face shield are essential to protect against splashes and burns. Safety glasses
alone do not provide sufficient splash protection .
2. What information is found on a Safety Data Sheet (SDS)?
A. Only the chemical name and formula
B. Physical and chemical properties, health hazards, first aid measures, and handling
precautions
C. The purchase price of the chemical
D. The name of the manufacturer only
:B
Explanation: An SDS provides comprehensive information about a chemical substance,
including physical and chemical properties, health hazards, first aid measures, handling and
storage precautions, exposure controls, and disposal considerations .
3. What is the primary purpose of a fume hood in the laboratory?
A. To provide additional storage space
B. To contain and exhaust hazardous vapors, gases, and fumes away from the analyst
C. To keep samples at a constant temperature
D. To prevent contamination of reagents
:B
Explanation: Fume hoods are engineering controls designed to protect laboratory personnel
by containing and exhausting hazardous airborne contaminants. They are essential when
working with volatile or toxic chemicals .
4. Which of the following is an example of an engineering control for laboratory safety?
A. Wearing safety goggles
,B. Using a fume hood
C. Reading the SDS
D. Following standard operating procedures
:B
Explanation: Engineering controls are physical modifications to the workplace that reduce
hazards. A fume hood is an engineering control. Safety goggles are PPE. Reading the SDS and
following SOPs are administrative controls .
5. What does the acronym "SDS" stand for in laboratory safety?
A. Standard Data Sheet
B. Safety Data Sheet
C. Sample Data Sheet
D. Standard Deviation Sheet
:B
Explanation: SDS stands for Safety Data Sheet, formerly known as Material Safety Data Sheet
(MSDS). It is a standardized document required by OSHA's Hazard Communication Standard
that communicates the hazards of chemical products .
6. What is the appropriate first aid for a chemical splash to the eyes?
A. Rub the eyes gently
B. Flush eyes with water for at least 15 minutes
C. Apply eye drops
D. Cover the eyes with a bandage
:B
Explanation: Immediate and thorough flushing of the eyes with water for at least 15 minutes
is the recommended first aid for chemical eye splashes. This helps dilute and remove the
chemical before it causes permanent damage .
7. Which class of fire extinguisher is used for flammable liquids such as gasoline, oils, and
solvents?
A. Class A
B. Class B
C. Class C
D. Class K
:B
Explanation: Class B fire extinguishers are designed for flammable liquids and gases,
including gasoline, oils, solvents, and paints. Class A is for ordinary combustibles, Class C is
for electrical fires, and Class K is for cooking oils .
8. What is the correct order of actions in the event of a fire in the laboratory?
A. Use a fire extinguisher, call 911, evacuate
B. Evacuate, pull the alarm, call 911, use extinguisher only if safe
C. Run and hide
, D. Call your supervisor first
:B
Explanation: The priority in a fire emergency is life safety: evacuate and activate the alarm
immediately. If the fire is small and safe to approach, use an extinguisher, but only after
evacuation and alarm activation .
9. According to Cal/OSHA requirements for a Grade 4 Laboratory Director, what document
must be reviewed and updated annually to ensure compliance with hazardous chemical
exposures in the workplace?
A. The Standard Operating Procedure (SOP) manual
B. The Chemical Hygiene Plan (CHP)
C. The Safety Data Sheet (SDS) inventory binder
D. The Emergency Action and Fire Evacuation Plan
:B
Explanation: Cal/OSHA requires that every laboratory utilizing hazardous chemicals maintain
and annually update a Chemical Hygiene Plan (CHP) specifically designed to protect workers
from physical and health hazards .
10. A laboratory analyst experiences chemical burns from a concentrated sulfuric acid spill.
Which administrative control must a Grade 4 Manager ensure was functioning to satisfy
immediate safety compliance?
A. Checking the expiration date on the employee's personal respirator
B. Verifying that the emergency eyewash and safety shower were inspected weekly and
provide tepid water
C. Reviewing the laboratory's liability insurance policy limits
D. Initiating an immediate formal reprimand file for the worker
:B
Explanation: Weekly verification and physical testing of safety showers and eyewash stations
are mandatory safety protocols under OSHA/Cal-OSHA to ensure mechanical reliability and
adequate water pressure in an emergency .
11. Hood flow should be monitored and documented at:
A. 50 linear feet per minute
B. 100 linear feet per minute
C. 150 linear feet per minute
D. 200 linear feet per minute
:B
Explanation: Hood flow should be monitored and documented at 100 linear feet per minute
to ensure adequate containment of hazardous vapors .
12. Standard phenylarsine oxide solution (PAO):
A. Is safe to handle without precautions
B. Should be handled with caution because it is a severe poison
