Three mile island hra using therp: part 1

 

We will be using the Three Mile Island incident to demonstrate how a Technique for Human Error Rate Prediction (THERP) analysis is done. First, take a look at this Summary Sheet on THERP (PDF) (Links to an external site.) hosted by Alion’s System Reliability Center website.

Next do the following activities. Steps 1-3 of the Summary Sheet on THERP are given below as a guide for your THERP analysis:

Step 1: Define the system or process. This involves describing the system goals and functions and the consequences of not achieving them. It also requires identifying mission, personnel, and hardware/software characteristics.

The “Meltdown on Three Mile Island” video ( 

https://www.youtube.com/watch?v=D8W5hq5dsZ4)in Module 1 gave you an understanding of the situation on that fateful day, Wednesday, March 28, 1979. Review the video if needed (use time segment 3:15 – 4:10 to focus on the key aspects needed for this assignment).

Step 2:  Identify and list all the human operations performed and their relationships to the system or process tasks and functions. This requires an analysis of all operator and maintainer tasks.

Take a look at the human operations depicted in the Fault Tree (PDF) of what occurred in segment 3:15 – 4:10 of the video. 

Step 3: Predict error rates for each human operation or group of operations. Errors likely to be made in each task or subtask must be identified. Errors that are not significant in terms of system operation are ignored. This step includes estimating the likelihood of each error occurring and the likelihood of an error not being detected. 

For this step, use the Event Tree (PDF) provided to fill in the error rates.

Determine the basis human error probability (HEP) based on the event tree provided.  You will be using data found in the NRC: Handbook of Human Reliability Analysis with Emphasis on Nuclear Power Plant Applications (PDF) (Links to an external site.) (NUREG/CR-1278).  Go to Chapter 20 to see how to use the THERP tables to locate probability values.

For this case, the data sources in the NUREG/CR-1278 tables are shown for each action in the table below.  Given that the operators omitted a procedural step from a long (>10 items) list of procedures, what should the Basic Human Error Probability (HEP) for each action be?  

ActionsHEP (error factor)

Data Source in

NUREG/CR-1278

Operators fail to restore signal power

20-7 (2)

Operators fail to restore power to controls

20-7 (2)

Operators fail to close the relief valve

20-13 (2)

Operators fail to close the drain valve

20-13 (2)

Upload your event tree with associated Basic HEP for each branch of the tree.

Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
$26
The price is based on these factors:
Academic level
Number of pages
Urgency
Basic features
  • Free title page and bibliography
  • Unlimited revisions
  • Plagiarism-free guarantee
  • Money-back guarantee
  • 24/7 support
On-demand options
  • Writer’s samples
  • Part-by-part delivery
  • Overnight delivery
  • Copies of used sources
  • Expert Proofreading
Paper format
  • 275 words per page
  • 12 pt Arial/Times New Roman
  • Double line spacing
  • Any citation style (APA, MLA, Chicago/Turabian, Harvard)

Our guarantees

Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.

Money-back guarantee

You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.

Read more

Zero-plagiarism guarantee

Each paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.

Read more

Free-revision policy

Thanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.

Read more

Privacy policy

Your email is safe, as we store it according to international data protection rules. Your bank details are secure, as we use only reliable payment systems.

Read more

Fair-cooperation guarantee

By sending us your money, you buy the service we provide. Check out our terms and conditions if you prefer business talks to be laid out in official language.

Read more