ANSI Z21.94-2006 (R2021)/CSA 6.31-2006 (R2021)

Preface This publication represents a basic standard for safe operation, substantial and durable construction, and acceptable performance of flammable vapor sensor systems and components. It is the result of years of experience in the manufacture, testing, installation, maintenance, inspection and research on flammable vapor sensor systems and components. There are risks of injury to persons inherent in appliances that, if completely eliminated, would defeat the utility of the appliance. The provisions in this standard are intended to help reduce such risks while retaining the normal operation of the appliance. Part I: Construction 1.1 Scope 1.1.1 This standard applies to flammable vapor sensors and systems intended for use in gas-burning appliances. 1.1.2 Compliance of a flammable vapor sensor or system with this standard does not imply that it is acceptable for use in gas appliance control systems without supplemental testing as applied to the particular appliance design. 1.1.3 This standard addresses the details of construction, performance, and testing of flammable vapor sensors and systems used for sensing the presence of flammable vapors in residential applications. 1.1.4 This standard applies to a sensor and/or system for incorporation into a flammable vapor sensor system. The complete system shall be a single use or manual reset type. 1.1.5 The sensor shall not require calibration or shall be self-calibrating. 1.1.6 Sensors and systems covered by this standard shall not have means for field adjustment of the manufacturers specified flammable vapor sensor response curve characteristics. 1.1.7 This standard applies to a flammable vapor sensor or system capable of operating throughout a temperature range of 32°F (0°C) to 125°F (51.5°C). The manufacturer is allowed to specify temperatures below 32°F (0°C) and above 125°F (51.5°C).