Dual action pull stations.

When the first action is done, can it be undone without someone having to do the second action and thus set off the system?

On a lot of pulls, it’s just pushing something in that springs back automatically, or a cover that could easily be put back into place.

Are you talking about dual action or dual stage?

ex, on the sigcom style double action t-bars, ie fenwal, dmp, simplex, etc, its exactly as described above.