Safety Practice Questions for Level 3 · Advanced

1. Question 1

   A pump is locked out, its suction line is blanked, and its casing is safely drained to zero pressure. When the drain is closed, pressure returns each time another pump starts on the common discharge header. Casing temperature stays steady. Which source must the isolation plan address?

   1. Thermal expansion of water trapped in the casing
   2. Gravity pressure entering through the suction line
   3. Pressure left from the pump's last operating cycle
   4. Header pressure passing through the discharge isolation
   Show the answer

   Answer: D. Header pressure passing through the discharge isolation

   Pressure returns only when another pump starts on the common header, while the blanked suction and steady casing temperature rule out the other listed sources. The isolation plan must therefore address header pressure passing through the discharge-side isolation.

2. Question 2

   During a permitted entry, a nearby chemical transfer releases chlorine toward the space's ventilation intake. The entrants' four-gas meter has no chlorine sensor and shows normal readings. Which action has priority?

   1. Arrange chlorine testing at the ventilation intake
   2. Have the transfer crew isolate the chemical source
   3. Order the entrants out and suspend the entry
   4. Move the intake upwind
   Show the answer

   Answer: C. Order the entrants out and suspend the entry

   A chlorine release threatens the entry atmosphere, and the four-gas meter cannot detect chlorine. The immediate priority is to remove entrants and suspend the entry; source control, testing, and ventilation changes can be handled by others, in parallel or afterward, under the site's emergency and entry procedures.

3. Question 3

   A storage review finds that sodium hypochlorite and acid tanks have separate, correctly sized containment areas. However, both containment drains lead to one common sump. Which proposed change addresses the remaining chemical-mixing hazard?

   1. Increase common-sump pumping to shorten chemical contact time
   2. Use independent collection systems with no common connection
   3. Raise both containment walls to add spill storage volume
   4. Add a high-level alarm and automatic sump shutdown
   Show the answer

   Answer: B. Use independent collection systems with no common connection

   Separate containment walls do not prevent incompatible chemicals from meeting if both areas drain to the same sump. Independent collection systems with no common connection remove that shared path and directly address the mixing hazard.

4. Question 4

   A platform task requires reaching an unguarded edge. The proposed fall-arrest system needs 18 feet of clearance, but only 12 feet is available. The existing restraint system cannot reach the work point. A portable guardrail system approved for the platform is available. Which plan should be used?

   1. Use fall arrest with a shorter lanyard and extra rescue worker
   2. Lengthen the restraint line and assign a safety monitor
   3. Install the approved guardrail before starting work
   4. Use a warning line with a dedicated spotter
   Show the answer

   Answer: C. Install the approved guardrail before starting work

   The proposed fall-arrest system lacks the required clearance, and extending the restraint system would allow access to the fall hazard. Installing the approved guardrail provides a suitable barrier at the edge before the task begins.

5. Question 5

   A supervisor reviews weekly eyewash records and finds that weak flow was documented three times. The unit remained marked available, corrosive work continued, and an open repair ticket was never verified closed. Which procedure change best corrects the program gap?

   1. Shorten the interval between activation checks and add a second weekly check
   2. Require an operable alternate eyewash or stop corrosive work
   3. Review open eyewash repair tickets during the next scheduled annual inspection
   4. Record the measured flow while leaving the unit available
   Show the answer

   Answer: B. Require an operable alternate eyewash or stop corrosive work

   The records already identified a repeated problem, but the deficient unit remained in service and corrective action was not verified. Requiring an operable alternate eyewash or stopping corrosive work closes the gap between finding a deficiency and protecting workers until it is corrected.

Operator Master has 11 Level 3 · Advanced safety questions, free.

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