Histology Certification Laboratory Safety 2 — Questions and Answers
Question 1: Which class of fire extinguisher is appropriate for a chemical solvent fire in a histology lab?
- Class A
- Class B (Correct answer)
- Class C
- Class D
Correct answer: Class B
Class B extinguishers are designed for flammable liquid fires, including chemical solvents such as xylene and alcohol.
Question 2: What is the correct first action when a histology technician splashes formalin into their eyes?
- Apply neutralizing eyedrops immediately
- Flush eyes with water at an eyewash station for at least 15 minutes (Correct answer)
- Wipe eyes with a dry cloth and seek medical attention
- Apply a cold compress and call poison control
Correct answer: Flush eyes with water at an eyewash station for at least 15 minutes
Immediate, prolonged flushing at an eyewash station for a minimum of 15 minutes is required to dilute and remove formalin from the eyes.
Question 3: In the hierarchy of controls, which measure provides the highest level of protection against hazardous chemical exposure?
- Administrative controls
- Personal protective equipment
- Engineering controls
- Elimination or substitution (Correct answer)
Correct answer: Elimination or substitution
Elimination or substitution removes the hazard at the source and is ranked highest in the hierarchy of controls.
Question 4: Which OSHA standard specifically governs occupational exposure to formaldehyde in U.S. laboratories?
- 29 CFR 1910.1048 (Correct answer)
- 29 CFR 1910.1200
- 29 CFR 1910.132
- 29 CFR 1910.1030
Correct answer: 29 CFR 1910.1048
29 CFR 1910.1048 is OSHA's Formaldehyde Standard, setting permissible exposure limits and required controls.
Question 5: A histology lab receives a new chemical. Which document must accompany it and be accessible to all staff?
- Certificate of Analysis (CoA)
- Safety Data Sheet (SDS) (Correct answer)
- Material Purchase Order
- Biological Safety Level Assessment
Correct answer: Safety Data Sheet (SDS)
Safety Data Sheets (SDS) are legally required to accompany hazardous chemicals and must be readily accessible to employees.
Question 6: Which personal protective equipment combination is minimum standard when handling xylene in an open container?
- Gloves only
- Lab coat and safety glasses
- Chemical-resistant gloves, lab coat, safety glasses, and use in a fume hood (Correct answer)
- Surgical mask and nitrile gloves
Correct answer: Chemical-resistant gloves, lab coat, safety glasses, and use in a fume hood
Xylene is a flammable, CNS-toxic solvent requiring chemical-resistant gloves, a lab coat, eye protection, and ventilation control via a fume hood.
Question 7: What is the permissible exposure limit (PEL) for formaldehyde as an 8-hour time-weighted average set by OSHA?
- 0.1 ppm
- 0.75 ppm (Correct answer)
- 1.0 ppm
- 2.0 ppm
Correct answer: 0.75 ppm
OSHA's PEL for formaldehyde is 0.75 ppm as an 8-hour TWA, with a short-term exposure limit of 2 ppm.
Histology Certification Laboratory Safety 2
Which class of fire extinguisher is appropriate for a chemical solvent fire in a histology lab?