Hello Pal
Thank you for contacting us. Sulphur acid is a harmful chemical (it corrodes the sensor easily) that must be kept away from the dew point transmitter. If the exposure of the Sulphur acid can be minimized, then you can choose the right product depending on the dewpoint measurement range you are looking for. One useful chart to choose the right product can be found here: https://www.vaisala.com/sites/default/files/documents/CEN-G-CompAir-Product-Brochure-B211208EN.pdf.

Best regards
Juhani, Product Manager