Re: Fire Risk ?
The interesting thing of Diesel , Natural Gas, etc ... they are stored in tanks, outside of your building.
If you want, you can put 3 sided walls around the tank (cinder block w concrete and rebar inside) to help direct the blast away from the building. The fourth side is open to allow access for refilling tank. (You could even put up a blast wall on that side too but away from the tank. )
Most of the energy and flame from the blast goes up.
That said... there are some newish developments on the Li battery tech that reduces the risk of fire. Still, if it were my DC ... I'd isolate it as much as possible. Definitely a firewall/blast wall and try to direct a blast upward.