🔍 Key Concepts

• Response time of gas detection instruments such as oxygen indicators • Manufacturer’s recommended stabilization or sampling time before taking a reading • Difference between real-time sensors and those that require a brief delay for an accurate measurement

💭 Think About

• Think about whether gas concentration readings change instantly, or whether the instrument usually needs a short period to stabilize after drawing in a sample. • Consider what would be safer in a confined space: taking the very first flickering reading, or waiting a short, specific time for a stable value. • Compare the options and ask: which time delay is commonly associated with letting a meter settle, without being unnecessarily long?

✅ Before You Answer

• Check what a typical oxygen indicator response time is in training materials or manufacturer guides. • Verify whether the exam is likely to prefer a specific settling time rather than saying "immediate" or a very long delay. • Confirm that the chosen option allows the reading on the meter to stabilize rather than relying on an instantaneous, possibly fluctuating value.