Smoke control design to CEN/TR 12101-5Paul Compton Colt International Limited 1 LOGO CEN/TR 12101-5: Smoke and heat control systems – Part 5: Guidelines on functional recommendations and calculation methods for smoke and heat exhaust systems. 2 LOGO . Contents Introduction How to use the TR Results The future 3 LOGO . History Based on British design methods: -Fire papers 7 & 10 1963 & 1964 -BR 34 1979 -BR 186 1990 -BR 258 1994 -BR 368 1999 -BS 7346-4 2003 4 LOGO . It is used when there is insufficient agreement for an EN. It does not have the same authority as an EN.Why a CEN/TR? A CEN/TR is a Technical Report. LOGO 5 . Doesn’t cover equipment selection or installation (CEN/TR 12101-4). 6 LOGO .Purpose of the TR Fire Size Guidance to designers on function and steady state calculation of SHEVS. mass and volume flow rates. aerodynamic area of exhaust and inlet and minimum number of exhausts. Time Gives zoning. Not very user friendly layout. More research is needed to improve some calculations. 7 LOGO .Weaknesses Limited guidance on fire size. Best spill plume calculation is difficult to use. 8 LOGO . Authorities checking designs also need knowledge so they can do more than simply check the maths. knowledge and training.Who should use CEN/TR 12101-5 Intended for people with suitable understanding. 9 LOGO .How to use it – criteria The starting point is to know what the system is for and what criteria need to be met: -Maximum smoke layer temperature -Minimum clear layer height -Maximum air inlet velocity. not maximum possible size -Realistic maximum before control by sprinklers or fire fighters -Realistic high and low heat outputs. LOGO 10 .How to use it – design fire This is the most critical part of the design: -Pre flashover. How to use it – smoke reservoirs Design formulae in the TR do not allow for cooling of the smoke layer. The 60m limit separately limits travel distance for evacuation under the smoke layer. -Heat losses by conduction and radiation should be separately calculated. 11 LOGO . or. Therefore: -Maximum reservoir areas are limited to keep cooling low enough to be ignored. Cooling of the smoke layer due to sprinklers is explicitly included in the calculations. The heat output per m2 is unchanged.Interaction with sprinklers Sprinklers allow use of a smaller design fire. Guidance on initiation gives priority to sprinklers unless the SHEVS is a life safety system. 12 LOGO . Options The standard is deliberately written with all calculations in Informative Annexes. such as NFPA 92 or 204. This allows use of alternative calculation methods. Mixing calculation methods is not recommended. LOGO 13 . Follow one method throughout. while still following 12101-5. 14 LOGO . There is still much work to be done to turn this into an installed system.Results Following this standard provides design flow rates and ventilation areas. CEN/TR 12101-4 and/or national guidance can be used for this. probably the best. 12101-5 will need to change to match it – but probably not for at least 5 years. In the meantime – used properly – CEN/TR 12101-5 is a good guide. 15 LOGO . It takes a more “European” approach.The future 12101-12 for time dependent design is being written. The end 16 LOGO .