🔍 Key Concepts

• Differences between CO₂ extinguishers and other types (like dry chemical or water) • How you can tell if a CO₂ extinguisher is still properly charged when it usually does not have a pressure gauge • Typical inspection requirements on a MODU (Mobile Offshore Drilling Unit) for fixed and portable extinguishers

💭 Think About

• Think about the physical design of a CO₂ extinguisher: what simple, objective feature changes when some CO₂ has leaked out, even if very slowly over time? • Which method would allow you to detect a small loss of charge without reducing the extinguisher’s remaining firefighting capability? • On an offshore unit, why might an inspector avoid any method that risks partially using up the agent during a routine check?

✅ Before You Answer

• Compare which choices would consume or alter the CO₂ charge versus which would leave it untouched. • Ask yourself which option would still work if the extinguisher has no pressure gauge on the valve assembly. • Consider which method is commonly used in industry to verify the charge of high‑pressure gas cylinders (like CO₂ bottles) during periodic inspections.