Is there a way to check if a high voltage generator is safe?

[unbuildpain]

I bought a 400KV high voltage generator, it looks like tube, a pair of wires stick out from two holes at the top and bottom. Can I run any tests with a digital multimeter or any other device to see if it is working and it is safe to use?

 

[dick_freebird]

Safety depends on many externalities. Those
HV generators look to have no safety features
(aside from primary:secondary isolation) and
as soon as you close the ground loop (with
wire, or meat) then it's all on practices more
than materials.