Press Release Water Quality
October 2023, Sensirion AG, 8712 Stäfa, Schweiz

SWT50i: Sensirion’s first water quality sensor

Sensirion’s new SWT50i sensor is the first product in the family of water quality sensing. The sensor uses a UV-absorption-based measurement principle and impresses with small size, easy integrability and cost-effectiveness.

The SWT50i sensor helps to assess organic substances in water and supports the user in controlling water treatment processes or monitoring the water quality. The sensor acts as photometer, measuring the absorption in the UV-C range and allows the user to monitor typical organic contaminants and various pollutants such as benzene and antibiotics, pesticides, detergents, plastics, and solvents. The exceptionally small size of 70 x 70 x 70 cm and flow through-design enables easy integration into challenging designs while meeting the highest reliability demand and cost-efficiency.

Organic pollutants, climate change and the associated water shortage are putting increased strain on the precious resource of water. Measurement technology plays a major role here, helping to increase the efficiency of purification processes, monitor their effectiveness or ensure compliance with legal guidelines.

Conventionally, the measurement of such pollutants is done at only a few points by means of TOC (total organic carbon) analyzers. These laboratory instruments are expensive, complicated to use and do not allow real-time monitoring. Additionally, there is the UV absorption method, based on the UV light absorbing property of organic molecules. While online measuring devices exist, which so far, they have been designed exclusively as probes and are also quite expensive.

The SWT50i uses the same measuring principle (UV absorption) but presents a completely new form factor at an attractive price. This allows measurement at several points in one system or in applications where it was previously not feasible in terms of price. In addition, Sensirion uses a flow-through sensor, which, unlike the available probes, can be easily inserted into closed hose systems with smaller hose diameters (5-15mm).

The SWT50i is part of Sensirion's vision to enable area-wide sensor networks in order to better record processes or the environment. This allows for a more efficient and resource-saving use of the precious resource water. With this sensor, the sensor specialist Sensirion enters the stage of water quality measurement for the first time. With cost-efficient and easy-to-integrate sensors, Sensirion wants to enable water quality measurement across the board: in production processes, water purification in waterworks to distribution systems or in private households.

For more information about the SWT50i water quality sensor, please visit Sensirion’s website at:

About Sensirion – Experts for Environmental and Flow Sensor Solutions

Sensirion is one of the world’s leading developers and manufacturers of sensors and sensor solutions that improve efficiency, health, safety, and comfort. Founded in 1998, Sensirion now employs around 1’000 people at its headquarters in Stäfa, Switzerland and in numerous international subsidiaries. Sensirion sensors can be used to measure a wide range of environmental parameters and flow rates precisely and reliably. The company’s aim is to make the world smarter with pioneering sensor technology. As a pioneer in innovation, Sensirion develops solutions for the specific needs of customers and partners from the automotive, industrial, medical technology and consumer electronics markets, as well as high-quality products for cost-efficient mass production. More information and current key figures at