What is a smoke and heat exhaust ventilation system (SHEVS)? Abbreviation, function and structure explained simply.

Building owners, architects, and facility managers frequently encounter the term "smoke and heat exhaust ventilation system" (SHEVS) when planning windows and facades – often without knowing exactly what it means. The principle is quite simple: In the event of a fire, a SHEVS automatically ensures that smoke and heat are extracted from the building in a controlled manner before they block escape routes or endanger the supporting structure.

RWA: What does the abbreviation mean?

RWA stands for smoke and heat exhaust ventilation system. In the event of a fire, these systems automatically open windows, skylights, or vents in the facade and roof to allow smoke and hot combustion gases to escape. This keeps stairwells and corridors clear for escape and firefighters, while simultaneously protecting steel and wooden structures from the destructive heat of a fully developed fire.

How does a smoke and heat exhaust ventilation system (SHEVS) work?

If a smoke or fire detector is triggered, the smoke and heat exhaust ventilation (SHEV) control panel sends a signal to the electric window actuators, which automatically open the designated smoke extraction areas. Each system can also be manually activated via a manual release, for example, by emergency responders on site. To ensure this process functions reliably in an emergency, the system is also protected by an emergency power supply in the event of a power outage.

What components make up a smoke and heat exhaust ventilation system (SHEVS)?

A typical smoke and heat exhaust ventilation system consists of four components:

• Triggering devices such as smoke and fire detectors or manual release buttons
• A smoke and heat exhaust ventilation (SHEV) control panel that evaluates alarm signals and controls the drives.
• Electric window drives (Chain, linear, spindle or rack drive) that opens the smoke extraction surfaces
• An emergency power supply that ensures functionality even during a power outage.

Smoke and heat exhaust ventilation system and daily ventilation: one system, two tasks

In many buildings, the same window actuators handle both fire protection and everyday ventilation – for example, in stairwells, factory halls, or office buildings. We explain in detail how both functions can be effectively combined in a single system in our article. SHEV and daily ventilation.

What matters when it comes to the quality of a smoke and heat exhaust ventilation system (SHEVS).

Because a smoke and heat exhaust ventilation system (SHEVS) must function flawlessly in an emergency, reliability is paramount, more so than with any other building technology. Drive quality, compliance with standards – including DIN 18232 – and regular maintenance determine whether the system will actually activate in the event of a fire. A detailed overview can be found in our article. Quality criteria for window drives.

How often a SHEV system must be maintained and inspected and what matters for the window actuators is explained in the guide SHEV maintenance: inspection duties and intervals.

Conclusion

A smoke and heat exhaust ventilation system (SHEVS) is therefore much more than just a window that opens: it's a safety-relevant system comprising sensors, controls, and drive technology that can save lives in an emergency. When planning, it's worthwhile to consider the drive type, quality, and installation situation together from the outset – we would be happy to advise you personally.

Read more: Smoke Vent in the Stairwell: Requirements, Opening Size and Operation

You can find suitable drives for your smoke and heat exhaust ventilation system at Smoke and heat exhaust ventilation (SHEV) drives for windows and skylights.

Which standards apply to smoke ventilation and what they mean for window actuators is explained in our overview Smoke ventilation standards: DIN EN 12101-2, DIN 18232 and building codes.