In the book One Second After author explains consequences from electromagnetic pulse (EPM) attack.
We have some critical infrastructure with limit budget, so we wonder how we can calculate EMP protection from simple aluminum foil or any other home material (any suggestions and how to estimate protection)?
What if device connected to electric grid, will Circuit breaker save it?
What if device connected to electric grid, will Circuit breaker save it?
Circuit breakers are designed to prevent fires due to wires over-heating. They typically take a significant fraction of a second or even several seconds to activate when an overload condition occurs.
A circuit breaker is unlikely to provide useful protection against an EMP. Similarly, we don't expect a breaker to provide protection from ESD, lightning strikes, or other short transient events.
A ground fault interrupter (GFCI) or residual current device (RCD) might be included as part of a circuit breaker. This is designed to prevent electric shock due through an alternate path to ground (through the user) that doesn't use the usual neutral wire. These react more quickly than a circuit breaker, but also aren't likely to protect from an EMP, since the EMP likely delivers too much energy for the RCD to interrupt adequately.
