Should the Abort Switch be installed inside or outside the room?

If you are protecting a room with a Clean Agent Fire Suppression System (such as FM-200 or Novec 1230), your primary goal is to protect critical equipment while ensuring life safety.

A core component of this system is the Abort Switch. Its purpose is to allow an occupant to manually delay the gas discharge in the event of a false alarm, ensuring people have enough time to evacuate safely.

So, where should the Abort Switch be located?
According to NFPA 2001, Section 4.3.5.1.1 (and specifically referenced in the installation guidelines of Section 9.6):

The Abort Switch must be installed inside the protected area, located near the exit door.

Why the location matters (The Logic):
Immediate Response: If a detector is triggered falsely while an occupant is inside, they need to stop the discharge immediately. If the switch were outside, the occupant might not reach it in time before the countdown ends.

Safety During Egress: Placing it near the exit allows the person to hold the button while moving toward safety, ensuring they are at the point of exit when they finally release it.

Preventing External Interference: If the switch were located outside, a passerby might accidentally or randomly delay a legitimate discharge, allowing a real fire to grow and cause catastrophic damage.

Technical Detail: The "Dead-Man" Type
Per NFPA 2001 Section 4.3.5.4, the code requires that the abort station be of a type that requires constant manual pressure to cause the abort. This is known as a "Dead-Man Switch." * How it works: As long as you keep your finger on the button, the countdown is paused. The moment you release your hand, the timer resumes its countdown to discharge. This ensures that the system is only delayed if a human is physically present to confirm the need for a delay.