What is SHEV?
A smoke and heat exhaust ventilator (SHEV) opens roof or wall flaps in case of fire, letting smoke, heat and combustion gases escape upwards. Escape routes stay smoke-free, fire brigades can advance and the structure is relieved (less heat build-up).
Three technical variants: electric (spindle drive, typically 24 V DC with battery backup), pneumatic (CO₂ cartridge drives a piston), pyrotechnic (initiator blows the flap open).
Intervals: annual and semi-annual
applicable proof of usability "SHEV — natural smoke vents" and applicable proof of usability mandate annual service by a competent person. Additionally, MLüAR NRW requires semi-annual operator visual checks.
Central components like SHEV control units are subject to additional testing per DIN VDE 0833 (fire-alarm systems).
What is serviced?
Flaps: travel, spindle/cylinder, seal, latch. Release: manual (SHEV button), automatic (smoke detector, alarm signal), thermal (pyro: fusible link). Power: mains, battery, backup — capacity test for electric systems. Controls: SHEV panel, line monitoring, multi-zone logic. Documentation: protocol with photo, defects, next test date.
Typical deficiencies
Jammed flaps from corrosion / leaves / pigeon debris. Empty or deeply discharged batteries — most common cause of failed tests. Triggered detectors in SHEV loops not reset. Obsolete control panels without spares. Missing adjustment after rebuild (smoke zones changed, SHEV design not updated).
Cost
Per SHEV flap: €45–120 annual service by type. SHEV panel: €80–250 by size and redundancy. For larger sites (> 20 flaps) frame contracts with annual flat-fee are standard. Battery replacement every 4–6 years: €80–200 per set.
Lessons from the Abels Brandschutz NRW service contracts: for an industrial hall with 24 flaps and a redundant control unit, a typical annual service flat-fee is €1,800–2,600 net, including half-yearly manual-trip-point inspection, emergency-power test and an electronic register.
How a SHEV service by Abels Brandschutz runs
A complete SHEV service in a mid-sized site (industrial hall with 15–25 flaps) takes us 4–6 hours. The sequence is standardised: pre-notification of the operator due to fire-detection trigger, disconnection from the fire alarm during the test, function test of every flap individually (manual and automatic actuation), flow and tightness measurement, battery capacity test under load, cleaning of smoke switches, documentation of every single flap with photo.
We work brand-agnostically — SHEV systems by Mercor, STG-Beikirch, Geze, D+H and Hekatron are our most common installations in NRW. Spare parts for common types are kept on stock; unusual components arrive within 1–2 working days. Where defects are identified, the operator decides: same-visit repair, separate repair order or temporary fix with defect notice to the insurer.
We produce the service documentation directly during the appointment as a digital PDF and upload it to the central register. Insurers and surveyors for preventive fire protection can be granted direct read-access on request.
Legal consequences of missed SHEV service
SHEV systems are part of the fire-protection concept in most NRW projects and therefore an obligation in the building permit. A missed service violates Building Code NRW (BauO NRW § 81) and the Special-Building Ordinances (e.g. VStättVO for assembly venues, KrhBauVO for hospitals).
After a fire with personal injuries the surveyor will check the SHEV's operational state. If the system was not serviced, it counts as 'not operational' — and insurance cover under VdS 2095 is at risk. For gross negligence the insurer can deny the claim, for ordinary negligence reduce it.
Criminal liability: in the event of a smoke-filled escape route with injuries or fatalities, prosecutors check for negligent homicide. A missing SHEV service record is regularly the anchor for personal liability of the managing director or owner.
Common mistakes in SHEV design and adaptation
SHEV systems are sized for a specific building geometry and fire-load assumption. If the building is later modified — new partitions, changed smoke zones, taller racking — the original SHEV design often no longer fits. The most common mistake we see: hall extensions with mezzanines added without recalculating the SHEV.
Before any significant rebuild, the fire-protection concept must be updated and the SHEV design reviewed. We offer a SHEV inventory analysis: comparison of the as-built state with the current fire-protection concept, inspection per the relevant proof-of-usability documents (DIN 18232-2 for natural SHEV, DIN EN 12101-2 for flaps, DIN VDE 0833 for control), and a retrofit recommendation.