24-Pet-B3 Petroleum Geology, May 2016, Q17

Question 17 of 22

Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)

Notes on this paper

National Exams, May 2016 — 98-Pet-B3, Oil and Gas Evaluation and Economics (3 hours, closed book, approved non-programmable calculator only). The exam's own cover page is titled "Oil and Gas Evaluation and Economics" and every question is property valuation / reserves & production economics / DCF-NPV screening content — no geology anywhere.

Reference texts: Thompson & Wright, Oil Property Evaluation; Canadian Oil and Gas Evaluation Handbook (COGEH), Vol. 1 (Society of Petroleum Evaluation Engineers, Calgary Chapter); National Instrument 51-101, Standards of Disclosure for Oil and Gas Activities (Canadian Securities Administrators); SPE/WPC/AAPG/SPEE Petroleum Resources Management System (PRMS); Economides & Nolte, Reservoir Stimulation; Ahmed, Reservoir Engineering Handbook.

The exam's own instructions ask for only 7 of the 10 short-answer questions and note the Cash-Flow/Future-Value tables are graded by column; for "choose N of M" exams, every item below is answered in full as a study resource. Questions 1–10 correspond to the exam's printed Short-Answer items 1–10; Questions 11–20 correspond to the printed Multiple-Choice items 1–10; Question 21 is the Future Value table; Question 22 is the Cash Flow table.

Question 17

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

a. After they have been abandoned
b. During some maintenance activity
c. During normal operations
d. At start-up
e. b) and d) above ← correct

Answer: (e). Process-safety incident statistics consistently show that non-routine periods — maintenance/turnaround activity (equipment opened up, isolations in place, non-standard procedures) and start-up (equipment and process conditions being brought up from a static/depressurized state, often for the first time or after a shutdown) — carry disproportionately higher major-loss frequency than steady, normal operation. Standard operating procedures and automated safety systems are optimized for steady-state running, so deviations and human intervention during maintenance and start-up create more opportunities for error and equipment failure.

Topic: Process-safety risk by lifecycle phase

Key relations: None quantitative — a qualitative loss-history observation (widely documented by CCPS and major insurers' loss databases).

Why this works: Automated control and safety systems are designed and tuned around steady-state operation; maintenance and start-up both require manual intervention, temporary bypassing of some protections, and non-standard configurations, all of which raise the chance of an error or an undetected failure surfacing.

Common pitfall: Assuming the highest risk is during continuous normal operations simply because that is where most operating HOURS are spent — risk PER HOUR is what is elevated during maintenance/start-up, not total exposure time.

Source: Thompson & Wright, Oil Property Evaluation, Ch. on operating risk; CCPS process safety guidelines.