Hello I am in a bit of an engineering bind. I need to evacuate a small room of a flammable, explosive gas that is at a nominal pressure of 3 mbar by pushing it from room to another room (both at equal pressure). The environment is Class 1 Div 1. The rooms have valved piping that enable me to attach a device to the exterior. The main difficulty with this project is that the device has to be portable. So anything electrically driven from an external power source is out of the question because plugging it in could create a spark (also any blowers I have seen are far too large of a capacity). I have examined some pneumatically driven pumps that may work, but they are not designed for gases and most of them, even plastic ones, have some steel parts that could in the worst case scenario spark. Also these pumps are designed for liquid use so a gas may not work. So now I am stuck. I have considered hand pumps, but again most of these have components that could spark and are designed for liquids. What would be ideal would be a small, battery ran, explosion proof Class 1 Div 1 certified blower. If anybody has any suggestions I would greatly appreciate it.