What if they blow into your face? :/

Then you learn about how the medical system works. Everything present a learning opportunity; it's up to you to embrace it and earn some benefit.

Just to be clear, don't embrace the steam engine.

Why, because the engine won't reciprocate?

Not while they're trying to do their job at any rate.

Epic !

At least you'll have an interesting epitaph.

"Here lies isoprophlex. An insufferable hothead, like his miniature steam engines."

You hydrostatic test them at a multiple of their working pressure.

This uses water instead of steam. If something lets go, the energy released is relatively small.

Before that you should have more fear of the lathe.

Yeah and maybe buy the pressure-tank (with over-pressure valve) or just use pressured air.

And if the machine itself blows up...even more fun to repair and improve it.