I'm wondering if it's safe to put an energized circuit in a static shielding bag...as part of a high altitude balloon project.
I'm not too sure how these work, so I tried seeing if either the outside or inside of the bag was conductive on a regular multimeter, which I found that it was not.
I wouldn't put a high voltage spark generator in it but most other stuff will be OK - circuits won't break or burn-out because the resistance of the static bag is higher than a regular multimeter would read. Having said that some may be lower than a couple of Mohm.
This link might prove to be insiteful: -
Do antistatic bags have conductive interior, exterior or both?
Yes they do have conductive interiors and exteriors. However the surface of the bag has may mega-ohms of resistance per inch. If you would like a comparason, an antistatic bag is very similar to an anti-static mat.
If you have high voltage or extremely sensitive components/analog circuitry you may run into problems. Another problem that the normal user shouldn't have, but could be an issue, is if you are working on a board that has traces extremely close together.
One other note, is that if you seal the bag, it can act like a faraday cage, and prevent/inhibit radio signals from entering or exiting the bag.
Alternatively instead of putting the circuit inside of an antistatic bag, a better way may be to create a large ground plane on the circuit, and then use some TVS diodes like these to protect any important components.
While they might by slightly conductive, all you need to do is insulate your circuit, from the bag. Don't let any metal/conductive part touch the bag and you would be fine, for normal, non-high voltage circuits.
In working with folks in the military packaging industry, yes, static shielding bags do have conductive interiors and exteriors. Also, keep in mind there are 2 types of static shielding bags and one might be more suited for your purpose:
Metal In Static Shielding Bags Metal-In static shielding bags offer superior durability at a low cost. Enhanced durability is obtained with the metallized layer buried between the polyester and the polyethylene layers of the metal-in shielding. The metal-in layer prevents the penetration of damaging electrostatic fields. Tribocharging is minimized by specially processed, non-static-generating polyethylene. This type of bag is recommended when packaging static sensitive components.
Metal Out Static Shielding Bags Metal-Out static shielding bags are designed to protect against static-induced damage. The Metal-Out layer is close to the surface for low surface resistivity readings. The Metal-Out static shielding bags will dissipate a 5,000-volt static charge to zero in less than 100 microseconds.
