Which device is a non-pumped diffusion meter with chlorine alarms at 0.5 ppm (low) and 1.0 ppm (high)?

• A. MiniRAE 3000
• B. MX908
• C. QRAE
• D. ToxiRAE (1 gas)

Answer: (D)

The main idea is sampling method and gas type. A diffusion, non-pumped detector relies on gas diffusing into the sensor and is typically used for single gases like chlorine, with fixed, low/high alarm points.

The ToxiRAE (1 gas) fits perfectly: it is a diffusion-based, single-gas monitor with an electrochemical chlorine sensor and is configured to alarm at about 0.5 ppm (low) and 1.0 ppm (high). That combination—diffusion sampling for chlorine with those alarm setpoints—matches the description exactly.

The other devices are geared toward different uses: for example, a VOC detector like the MiniRAE 3000 is a PID and often used with pumped sampling, not a chlorine-specific diffusion monitor; the MX908 and QRAE are multi-gas instruments (often pumped) and not the simple non-pumped chlorine monitor with those exact alarm levels.