The BEE runs off of a dataset that's several thousand materials deep. That means we have lots of options, but we certainly don't have everything.

The datasets we run on are curated by external third parties. They do the work of peer reviewing and performing diligence on the emissions factors. So, in order for something to end up in the BEE, it had to be studied, reviewed and approved. There are some materials for which there aren't even life cycle assessments completed, let alone assessments that have found their way into the BEE.

If the BEE absolutely does not have the material you need, input a similar material. Metals are metals; plastics are plastics -- at the end of the day, the emissions factors are similar and this will still yield a reliable estimate. 

That being said, we are always working to bulk up our library. Write us if there's something significant that we're missing!