Tube Failure Detection (TFD) system Patent No. 7,001,153 and 7,284,964 No False Triggering! Breakthrough technology for Peristaltic Pumps. The TFD system will detect a wide range of chemicals (i.e. chlorine, acids, soaps, etc.). This unique technology was designed NOT to false trigger by condensation and washdown. Many companies require the TFD system for their peristaltic pumps.