IF senor value < - 10 for 12 seconds LED High

Hi,

Can anyone give me some advice on my coding.

What i need is:

IF senor value < - 10 for 12 seconds LED High else LED Low

Here's the relevant part of the code to add the above time (12 seconds too) :

if( pressure < -10) {
digitalWrite(ledPinRed, LOW);
}
else {digitalWrite(ledPinRed,HIGH);
}

IF you need anymore code just let me know.

Many Thanks!

You need to record when the sensor value goes below the threshold.
You need to record when the sensor value goes above the threshold.

If, at any given time, the sensor is below the threshold, and the time that it has been below the threshold is significant, for some definition of significant, do something.