Exit Buttons & Door Alarms for Access Control in Dubai

Staff badge in fine, but how do they get out? And who notices when a door is propped open all afternoon? A request-to-exit (REX) button, a door contact and a door-held-open alarm are small, low-cost parts that decide whether your access control system in Dubai works properly or generates false alarms and security gaps.

What Each Component Does

• Request-to-exit (REX) button or sensor: lets people leave through a locked door. It releases the lock and tells the controller the opening is authorised, so no forced-door alarm is raised.
• Door contact (magnetic reed switch): reports whether the door is open or closed.
• Door-held-open (DHO) alarm: triggers a local buzzer or alert if the door stays open longer than a set time.
• Forced-door alarm: triggers if the door opens without a valid card, fingerprint, or REX signal.

Why They Matter in Dubai Buildings

Offices, warehouses, clinics and residential towers across the UAE see heavy foot traffic and frequent deliveries. Doors get wedged open for trolleys, for cooling, or for convenience. Without a door contact and DHO alarm, nobody knows. Without a REX device, people get trapped behind a locked door or somebody forces it, setting off false alarms in your control room.

Types of Exit Devices

1. Push-button REX

The standard wall-mounted button. Simple, robust, affordable. Choose a metal, vandal-resistant model for car parks, plant rooms and outdoor areas where dust and humidity are a concern.

2. No-touch infrared REX

Wave your hand near the sensor. A good fit for clinics, labs, F&B and any area where hygiene matters.

3. PIR motion sensor

Detects approach from the secure side and unlocks automatically. Convenient, but mount it carefully so it cannot be triggered from the outside through gaps or glass.

4. Panic bar / push-bar exit device

Mechanical egress hardware used on exit routes. See our guide on panic bars and exit devices in Dubai.

Wiring Basics: How It Connects

1. The REX button connects to the controller's input (or the reader's exit input) and also cuts power to, or signals, the lock release.
2. The door contact connects to a separate monitored input on the controller.
3. The controller logic: valid credential or REX = authorised open; open with neither = forced-door alarm; open longer than the timer = held-open alarm.

Whether the lock is fail-safe or fail-secure also changes the design. Read fail-safe vs fail-secure locks before choosing. Standard Hikvision and UNV access controllers support door contact and exit inputs on their standard boards.

Setting the Right Door-Held-Open Timer

• Staff doors: short timer, typically 20 to 30 seconds, then a local buzzer.
• Loading and delivery doors: longer timer, or a time-schedule that allows extended open periods during delivery hours.
• High-security doors: alarm to the control room or mobile app, not just a local buzzer.

Settings should follow your site risk assessment and be confirmed against Dubai Civil Defence and your building's fire consultant, because exit routes must stay usable in an emergency.

Common Problems and Quick Fixes

• Constant forced-door alarms: REX not wired to the controller input, or the contact is misaligned. See our access control troubleshooting guide.
• Door will not unlock from inside: loose REX wiring or a dead button.
• False held-open alarms: gap between magnet and contact too wide after door sag, or the timer is too short.
• Contact fails often: dust and heat in outdoor or plant areas; use heavy-duty surface-mount contacts.

Quick Checklist for Facility Managers

1. Does every access-controlled door have a working REX or egress device?
2. Does every door have a monitored door contact?
3. Are held-open and forced-door alarms tested monthly?
4. Do alarms reach someone who will act on them?
5. Is it all covered under an AMC?

Get Your Doors Checked by Merac Dubai

Merac Dubai supplies, installs and maintains access control systems across Dubai and the UAE, including controllers, readers, locks, REX buttons, door contacts and alarms, plus automatic doors, gate barriers and CCTV. Our engineers can audit your existing doors and fix the gaps.

📞 Call or WhatsApp us for a free site assessment, or ask about an Annual Maintenance Contract (AMC) for your access control system.