ATEX Approved IS Relative Humidity Probes

Duct Mounting

The HP140IS is a Duct mounting Intrinsically Safe Relative Humidity transmitter.

It has been approved by Baseefa (2001) Ltd, certificate number Baseefa 03ATEX0101X/3, for use in Zone 20 conditions and is certified to  II 1 GD EEx ia IIC T4( -20°C <Ta <+ 70°C) T135°C GAS & DUST. The probes operate as a two wire transmitter and produces a 4 to 20mA output proportional to 0 to 100% Relative Humidity. Interface to the safe area must be via approved barriers. Baseefa (2001) Ltd have also approved the system drawings using MTL7728 –ve or MTL7788R+ve barriers. The system certificate number is Baseefa03Y0103.

Product Power Mounting SIL Downloads
HP140IS- Intrinsically Safe RH Transmitter N/A N/A No



Find out more

Our innovative instruments and systems have been used by all sectors of industry for over 50 years.

  • Probes, sensors and signal conditioning. 
  • Cloud-based Monitoring Systems engineered to your specification.
  • Remote Control and Monitoring Systems.


Find out more

Providing excellent service to all our customers is what Lee-Dickens is all about. In response to changing customer needs we have continued to adapt our product range and equally the services that we offer.


Our experienced Engineers can offer all the services necessary to take any product from concept through to full production.  

Our Cloud Hosted Monitoring Systems and IIOT services are attracting more amd more subscribers, and our commitment to customer service means our support team regularly exceed customers' expectations.