Servicing a composter in a tight space is tricky; the air quality might be bad, and raking and removing the end product difficult. Warning: Many odorless and invisible gases, such as carbon dioxide, carbon monoxide, sulfur dioxide, methane (natural gas), and radon are heavier than air and can fill up a foundation from external sources and displace the oxygen-carrying atmosphere. You cannot survive in such an anoxic environment. If you or a service person climbs down into the room that contains these gasses, you could be in big trouble and not know it until you pass out from lack of oxygen.