Shenzhen Wanyi Technology Co., Ltd. (brand CESTSEN), an established radon detection module manufacturer based in Shenzhen, China, is proud to announce the availability of the RAD-S51 radon gas sensor — a high-sensitivity silicon detector module engineered for long-term, continuous indoor radon monitoring. Since 2011, CESTSEN has dedicated itself to the research, development and manufacturing of air-quality measurement instruments, and the RAD-S51 reflects more than a decade of accumulated expertise in radiation and environmental sensing.
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The RAD-S51 measures radon gas concentration through static air diffusion. By taking advantage of the radioactive properties of radon and its decay products, the module collects alpha particles through a large-sized collection chamber and a silicon detector, and then converts the alpha counts via a precise signal acquisition system into an accurate radon concentration value. Because the measurement system is insensitive to humidity, the module maintains stable performance even in damp basements, mines and other demanding environments where conventional sensors tend to drift.
The detector offers a detection sensitive area of 100 mm2 (10 × 10 mm) and a sensitivity of 0.027 cph/[Bq/m3], enabling reliable tracking of radon levels across a very wide measurement range of 5 to 300000 Bq/m3 with a low detection limit of 5 Bq/m3.
| Indicator | Parameter |
|---|---|
| Detector | Silicon detector |
| Measurement object | Radon gas |
| Measurement range | 5 ~ 300000 Bq/m3 |
| Detection sensitive area | 100 mm2 (10 × 10 mm) |
| Sensitivity | 0.027 cph/[Bq/m3] or 0.982 cph/[pCi/L] |
| Detection limit | 5 Bq/m3 |
| Background count rate | ≤ 0.05 cph (Nitrogen) |
| Uncertainty | 120 hours later ≤ 10% (K=2) when radon concentration is greater than 200 Bq/m3 |
| Measurement time | ≥ 60 min |
| Working voltage | 3.3V |
| Power consumption | ≤ 3.3 mW |
| Communication protocol | 3.3V TTL level serial asynchronous output |
| Baud rate | 9600 bps |
| Working environment | -10°C ~ +50°C; RH ≤ 90% (at +45°C) |
| Storage environment | -25°C ~ +85°C; RH ≤ 90% (at +45°C) |
| Dimensions | 60 × 60 × 21 mm |
| Certification | CE, RoHS |
Engineered for professional markets, the module supports three core application fields:
As a manufacturer rather than a trading company, CESTSEN controls the entire production chain — from sensor design and firmware development to calibration and final quality inspection. With a workforce of 50 to 100 employees and 70 to 80 percent of production shipped to export markets, the company supplies distributors, environmental monitoring firms and instrument brands worldwide. The RAD-S51 is available for OEM and ODM cooperation, with adjustable parameters and a flexible interface that make it straightforward to embed into a partner's own monitoring system.
For wholesale pricing, samples and technical documentation of the RAD-S51 radon detection module, contact CESTSEN today and discover how a proven silicon-based radon sensor can elevate your next-generation monitoring product.