Technical Analysis: Systems, Radiation Protection, and Maintenance Package Development

Lesson Overview

This lab session is the technical heart of your capstone project. You will produce three interconnected work products—a system functional analysis, an ALARA radiation work permit (RWP) analog, and a lockout/tagout (LOTO) package—written to the professional standard expected of a nuclear plant training document. Each product must stand on its own, yet all three must describe the same scenario and the same system. That integration is what makes this capstone meaningful.

Section 3: System Functional Analysis

A system functional analysis answers four questions: What does this system do under normal conditions? What safety function does it perform when something goes wrong? What are its major components and their relationships? How does it interact with other plant systems?

Begin by reading your assigned Piping and Instrumentation Diagram (P&ID) carefully. Identify the system boundary—the outermost isolation valves that separate your system from adjacent systems. Mark every pump, heat exchanger, major valve, and instrument. Copy the instrument tag numbers exactly; tag numbers are how operators and engineers reference physical equipment in the field, and errors create confusion that can affect safety.

Document normal operating parameters: flow rates, pressures, temperatures, and fluid inventory levels that operators expect to see during steady-state power operation. These are your baseline. If a parameter leaves its normal band, an operator must know why. Your write-up should explain the consequence of each major parameter deviation.

Describe the safety function last, because it depends on understanding normal operation first. For example, a residual heat removal (RHR) system may run in standby during power operation, but its safety function—removing decay heat after shutdown—is critical to fuel integrity. Reference the specific design-basis event that activates the system.

Format Section 3 using the NEI NUCP Uniform Curriculum document conventions. Every figure must be labeled with a figure number and caption. A minimum of eight pages is required, but completeness and accuracy matter more than page count.

Section 4: ALARA Radiation Work Permit Analog

The principle of ALARA—As Low As Reasonably Achievable—requires that radiation exposure be reduced below regulatory limits wherever practical, not merely kept within them. The NRC dose limits in 10 CFR Part 20 set the legal ceiling; ALARA planning sets the practical target, typically a small fraction of that ceiling.

Your RWP analog documents the radiological conditions workers will encounter, the controls that will protect them, and the dose budget for the job. Use the radiological survey data provided with your scenario. Survey data typically gives dose rates in millirem per hour (mrem/hr) or microsievert per hour (µSv/hr) at specific measurement points. Apply the point-source or buildup-factor calculation methods you practiced in Course 5 to estimate dose rates at worker locations.

Specify dosimetry: at minimum, a passive whole-body dosimeter (TLD or OSL badge) is required for any work in a radiologically controlled area. A self-reading dosimeter or electronic personal dosimeter (EPD) allows real-time monitoring. If surface contamination levels exceed action levels, anti-contamination (anti-C) clothing is required. If airborne radioactivity is present above established limits, specify respiratory protection consistent with plant procedures and 10 CFR Part 20 requirements.

Calculate a stay time: divide your ALARA dose goal for the task by the expected dose rate at the work location. That quotient gives the maximum minutes a worker should spend in the area without exceeding the dose goal. Build in margin—radiation work rarely goes exactly as planned.

After your peer review using the instructor checklist, revise and finalize. Peer review is not a formality; it mirrors how licensed nuclear facilities use independent verification to catch errors before work begins.

Section 5: LOTO Package

Lockout/tagout protects workers from unexpected release of hazardous energy. In a nuclear plant, hazardous energy sources include electrical (motor-operated valves, pump motors), mechanical (rotating equipment), thermal (high-temperature piping), pneumatic (air-operated valves), and hydraulic (pressurized systems). Your scenario will involve more than one of these categories.

The OSHA standard at 29 CFR 1910.147 governs LOTO in general industry, and nuclear plants apply it alongside plant-specific procedures. The required steps are: notify affected employees; shut down the equipment using normal stopping procedures; isolate every energy source; apply locks and danger tags to each isolation point; release or restrain stored energy (bleed pressure, block valves against gravity, discharge capacitors); verify that the equipment cannot be energized by attempting to start it.

Your package must list every energy source—omitting even one is an automatic return-for-correction in this course, because a missed energy source in the field can kill a worker. Write step-by-step isolation procedures using the actual valve numbers from the P&ID. Include a verification checklist that a second qualified person signs. Include a danger tag log recording tag number, location, installed-by, and date.

After drafting, audit the package against the instructor-supplied 1910.147 audit form. Correct every deficiency before submission.

Safety Reminders

Through this lab you are writing documents that could guide real workers near radioactive systems and energized equipment. Treat accuracy as a life-safety matter, because in practice it is. When in doubt about a regulatory requirement, look it up in the primary source—10 CFR Part 20 or 29 CFR 1910.147—rather than relying on memory. Flag any uncertainty to your instructor before submission, not after.