Watchdog Application

[ScruffR]

Having interrupts turned off between iterations of loop() is no good idea.

As I already have pointed out to you in your other thread

@ScruffR

Just one thing to be careful about. While an Arduino doesn’t do a lot else than running your code, Particle devices do other stuff while not occupied with your code (e.g. cloud house keeping) which might get affected by disabling interrupts for prolonged periods.

You should only disable interrupts for very short times, e.g. only for a couple of instructions to transfer highly volatile variables.
Instead of using noInterrupts() I'd rather use ATOMIC_BLOCK for such cases.