Lesson 5.4 — Exercise
Exercise — Business Case for Adaptive Legionella Control at CERN
This is a self-guided activity. Download the detailed exercise handout, open the participant workbook in Google Sheets and complete the task in your own copy.
Lesson content
This exercise asks you to build a management-ready business case for an adaptive Legionella control solution at CERN, using a Year 0–8 cost-and-benefit model and a 3.5% discount rate.
What you will learn
- Define the status quo and do-nothing risks
- Estimate PCP, deployment and operating costs
- Quantify financial, safety and environmental benefits
- Interpret the calculated NPV
- Identify key risks, mitigations and evidence gaps
How to complete the exercise
The handout contains the complete scenario and assumptions. Use the Google Sheet to build and calculate your business case.
Enter benefits
Review automatic NPV
Explain assumptions and risks
Key terms
| Input cell | A cell intended for participant assumptions; formulas should not be changed. |
|---|---|
| Cash flow | The costs or benefits assigned to a specific year. |
| Sensitivity | How the conclusion changes when assumptions such as cost, benefit or timing are varied. |
| Mitigation | A planned action that reduces the likelihood or impact of a risk. |
What to deliver
Completed cost table + completed benefit table + automatic NPV result + a short explanation of the assumptions and risks that most influence the decision.
Before you continue
Reflection: Which assumption has the greatest effect on your NPV, and what evidence would make it more reliable?
Lesson resources: (1) downloadable S5 Exercise Handout — complete scenario, assumptions and task; (2) participant workbook in Google Sheets — input cells, formulas and the Year 0–8 model.
Access requirement: the handout must download correctly and the Google Sheet must open without requesting access.
