The first NH3 sensor for continuous measuring of the ammonia concentration in the house air

DOL 53 is an electrochemical, long-term stable NH3 sensor developed by the company Dräger. The sensor is very robust and well-suited for use in livestock facilities. The Big Dutchman group is the first and only equipment supplier offering this sensor.

DOL 53 permanently monitors the ammonia concentration in the house air, thus permitting the house climate to be controlled based on the sensor’s measurements. Our climate computers ViperTouch and 307pro can receive and process the data provided by the sensor to regulate the house climate according to the measured values. Additionally, the AC Touch alarm unit can record the data and use BigFarmNet to analyse them. If you need further options of viewing the measured values, please contact our sales staff.

DOL 53 provides exact figures on the NH3 concentration in the house air at all times so you can immediately take suitable measures to reduce the ammonia content when necessary. Because only healthy animals can show their full genetic potential!

NH3 measuring at an OptiSec dryer

Measuring the NH3 concentration in the exhaust air (with a separate display for testing purposes)


  • Exact and continuous measuring of the NH3 concentration in the house air
  • Measuring range covers concentrations typical for livestock production
  • Easy integration into existing houses and their climate control systems
  • Robust and reliable
  • Easy to install
  • Analogue 0 to 10 V output

1: Suspension easily height-adjusted

2: Cable with socket sensor can be removed easily for cleaning

3: Status LED indicates operating mode of the sensor

4: Robust shell well-suited for the conditions in the barn


  • Measuring range of the sensor: 0 to 100 ppm NH3
  • Accuracy: 1.5 ppm or ± 10 % of the measured value
  • Power supply: Rated voltage 24 V (15 to 30 V DC)
  • Current consumption: < 10 mA
  • Temperature range: 0 to 50°C
  • Humidity: 15 to 95 %
  • Dimensions: (WxHxD) 100 x 200 x 50 mm
  • Weight: 450 g
  • Protection rating: IP 65
  • Service life: 3 years from commissioning (expiry date: see label on the sensor)