CEN/TR 12101-5: Functional Recommendations and Calculation Methods for SHEVS
CEN/TR 12101-5 is a Technical Report giving design guidance and calculation methods for smoke and heat exhaust ventilation systems (SHEVS). It is used by fire engineers in SHEVS design: not a product specification. Smoke curtains are now covered by BS 8524, not EN 12101-5.
CEN/TR 12101-5 is a CEN Technical Report, not a harmonised European Norm. That means it provides guidance, calculation methods and recommended approaches for designing smoke and heat exhaust ventilation systems (SHEVS). It is not a standard that products are certified against, and products cannot carry a CE or UKCA mark “against EN 12101-5.”
Part of the BS EN 12101 standard family.
It was reclassified from the original product-spec form (which had previously dealt with smoke curtains) into its current Technical Report form in 2018. Smoke curtains are now covered by BS 8524, not EN 12101-5.
Who uses it
Fire engineers, M&E consultants, and SHEVS designers use CEN/TR 12101-5 to size and verify natural and powered smoke ventilation systems.
What it covers
The Technical Report addresses calculation methods and functional recommendations including:
- Smoke layer depth, temperature, and mass flow estimation
- Smoke reservoir sizing principles
- Inlet area and aerodynamic free area calculations
- Plume mass flow equations for axisymmetric, balcony and line fire sources
- Time-to-tenability principles
- Inputs and assumptions for steady-state SHEVS design
For time-dependent (transient) fire scenarios, designers should refer to prEN 12101-12 (currently in draft).
Relationship to UK standards
In the UK, CEN/TR 12101-5 sits alongside:
- BS 7346-4: Components for smoke and heat control systems: code of practice on functional recommendations and calculation methods for SHEVS, primarily for car parks
- BS 7346-5: Functional recommendations and calculation methods for SHEVS in covered car parks
- Approved Document B of the Building Regulations, which references the underlying performance objectives
Designers typically use UK code-of-practice methods (BS 7346 series, BS 9991, BS 9999) in conjunction with the calculation guidance in CEN/TR 12101-5.
Where this applies
CEN/TR 12101-5 is used in the design of smoke ventilation for:
- Single-storey buildings (shopping centres, warehouses, atria)
- Multi-storey buildings with smoke clearance requirements
- Car parks
- Atria and large-volume spaces
Common misconception: smoke curtains
EN 12101-5 used to be about smoke curtains. It no longer is. Smoke curtains in the UK are covered by BS 8524-1 (product) and BS 8524-2 (code of practice).
How Vent Trade can help
Vent Trade’s natural and mechanical smoke ventilation products are supplied with the certification and performance data needed for SHEVS design under CEN/TR 12101-5 calculation methods. We can also support specifiers with aerodynamic free area data, plume calculations input data, and product selection guidance.