I would strongly recommend you switch to carefresh or shredded aspen for your sand boa. It is a myth, based on their name, that they are always busied in the sand, but this is absolutely not true. In the wild, they tend to find burrows of other creatures to live in. Sure, they will bury in a particulate substrate if that's all they have, but let me ask you this.... if I buried you in cocnut fibre, would you be able to breathe? Guess what... they can't either.
Please consider aspen shavings or carefresh.
- Ken LePage