Great looking game!
What rules are you using for gas attacks?
Nicked from WH "Over the Top" supplement, suitably modified to fit in with Bolt Action. Throw a D6 for each unit score of 6 means it has been effective, it then causes D3 hits, D2 if a small unit, throw to damage as usual. Each unit hit must pass an order test, if it fails it receives a pin too.