Corrosive and Dangerous Gas Policy

Updated: July 26, 2023

This Corrosive and Dangerous Gas Policy is applicable for models: SmartTrak 50, SmartTrak 100 Series, and TopTrak 820 Series capillary products.

This policy is intended to offer specific information regarding the service and warranty of Sierra’s 50, 100 and 800 Series capillary products in applications where the gas to be used can corrode stainless steel.  This most often occurs with gases that, in the presence of air, become powerful acids. Usually, the result of removing an instrument from a proper installation. It is rarely the result of “wet” gas at your location or improper handling, though this is always a concern.  Instead, it is because of the difficulty encountered in completely purging the reactive gas from the instrument. When such a device is returned to our facility (where humidity is always present), it becomes exposed to moisture. This begins the corrosion process. The simple nature of removing such an instrument and returning it to us can damage the device.

Return Policy Concerning Scientific Units Exposed to Corrosive and/or Dangerous  Gases

Sierra’s 50, 100 and 800 Series capillary products are compatible with most gases due to their 316 stainless steel flow bodies and sensors, provided they are used with the recommended elastomeric seal material. However, these gases can often mix with other gases or liquids during use which can alter their chemical properties and create a corrosive or dangerous condition as noted above.

Because of safety concerns, Sierra has adopted a “Do Not Return” policy for meters and controllers subjected to the following gases:
Gas Name  Gas Symbol
Boron Trichloride
           Ethylene Oxide            C2H4O
Hydrogen Chloride
Hydrogen Fluoride
Hydrogen Sulfide 
Nitrogen Dioxide
           Tetraethyl Orthosilicate            Teos
Tungsten Hexafluoride
Sulfur Dioxide
Uranium Hexafluoride

Sierra Policy Summary

  1. Other gases that are not listed might also be considered corrosive or dangerous. Before attempting to return a device to the Sierra factory for service, please provide Technical Support with a Material Safety Data Sheet (MSDS) for approval before attempting to ship.
  2. Devices subjected to listed or non?approved gases are NOT to be returned to the Sierra factory for service or calibration, regardless of purging or cleaning.
  3. The normal 1-year warranty is void once the device is exposed to one of these gases.
  4. If a problem arises, contact Sierra Technical Support for a possible solution, or to order a replacement at a discount. Standard lead times apply.
  5. If a device has been calibrated for one of the above gases but has not yet been exposed to it, it may be returned for service. A signed Non?Exposure Statement must accompany the shipment. This document is provided on the Sierra Instruments website during the RMA process. If there is any question, please contact Sierra Technical Support during Pacific Time business hours. 
  6. An Ammonia device may be returned for service through the RMA process, provided a "Declaration of Decontamination" is included. 

Sierra Industrial Device Policy Summary

Industrial products such as 620, 640, 780, 240 and 241, if exposed to any of these gases, must be properly cleaned and purged in order to return for service. During the RMA process, a “Declaration of Decontamination” must be completed and signed, and an MSDS document supplied with the shipment.

Download PDF of Dangerous and Corrosive Gas Policy