CWD Safety Standards & Practices 2 — Questions and Answers
Question 1: When working near an energized power line during drilling operations, what is the minimum safe approach distance for equipment under 50 kV?
- 3 feet
- 10 feet (Correct answer)
- 20 feet
- 50 feet
Correct answer: 10 feet
OSHA requires a minimum 10-foot clearance from energized power lines up to 50 kV for equipment and workers.
Question 2: A confined space entry permit for a completed well vault must include which of the following?
- Weather forecast for the day
- Atmospheric testing results before and during entry (Correct answer)
- Equipment purchase date
- Well yield test data
Correct answer: Atmospheric testing results before and during entry
Atmospheric testing for oxygen, flammable gases, and toxic vapors must be documented before and monitored during confined space entry.
Question 3: Which type of fire extinguisher is appropriate for a Class C electrical fire on a drilling rig?
- Water-based extinguisher
- CO2 or dry chemical extinguisher (Correct answer)
- Foam extinguisher
- Wet chemical extinguisher
Correct answer: CO2 or dry chemical extinguisher
Class C fires involving energized electrical equipment require non-conductive extinguishing agents such as CO2 or dry chemical.
Question 4: What is the primary purpose of a Job Hazard Analysis (JHA) before beginning a well drilling project?
- To estimate project cost
- To identify and mitigate hazards associated with each task step (Correct answer)
- To document equipment serial numbers
- To assign crew overtime pay
Correct answer: To identify and mitigate hazards associated with each task step
A JHA systematically breaks down job tasks to identify potential hazards and establish controls before work begins.
Question 5: Hydrogen sulfide (H2S) gas encountered during drilling is most dangerous because it:
- Has an extremely pungent odor that is always detectable
- Desensitizes the sense of smell at high concentrations, giving no warning (Correct answer)
- Is heavier than air and always stays at ground level
- Reacts with drilling mud to form explosive compounds
Correct answer: Desensitizes the sense of smell at high concentrations, giving no warning
H2S paralyzes olfactory nerves at concentrations above 100 ppm, making the gas undetectable by smell at dangerous levels.
Question 6: Which lockout/tagout (LOTO) step must occur FIRST when servicing drilling rig hydraulic systems?
- Apply the tagout device to the energy source
- Notify affected employees of the shutdown
- Identify all energy sources including stored hydraulic pressure (Correct answer)
- Test the equipment to verify it is de-energized
Correct answer: Identify all energy sources including stored hydraulic pressure
Before any lockout device is applied, all energy sources — including residual hydraulic pressure — must be identified to ensure complete isolation.
Question 7: During drilling in a known pesticide-contaminated area, workers should wear at minimum which respiratory protection?
- Dust mask (N95)
- Half-face air-purifying respirator with organic vapor cartridges (Correct answer)
- Full-face supplied-air respirator
- No respiratory protection is required outdoors
Correct answer: Half-face air-purifying respirator with organic vapor cartridges
Organic vapor cartridges on a half-face APR provide baseline protection against volatile organic pesticide compounds during outdoor drilling.
CWD Safety Standards & Practices 2
When working near an energized power line during drilling operations, what is the minimum safe approach distance for equipment under 50 kV?