Official UL standards are proprietary and typically require purchase.
UL 2431 is a standard for Fire Alarm Systems, specifically covering requirements for Carbon Monoxide (CO) Detection. If you're interested in reading the PDF version of this standard, here are a few suggestions: ul 2431 pdf free
The standard subjects materials to various simulated environments to check for physical and chemical stability: Official UL standards are proprietary and typically require
Outdoor, Heavy Industrial (the most stringent, often required for UL 1709 certification). Category II: Indoor, General Purpose. Category III: Indoor, Controlled Environment. How to Access UL 2431 Legally Heavy Industrial (the most stringent
The standard subjects fire-resistive materials (such as intumescent or cementitious coatings) to rigorous conditioning to simulate long-term exposure: