Case Study 2 Production and Storage. SFPE Polish Chapter Wojciech Węgrzyński, Grzegorz Krajewski Building Research Institute (ITB)

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2 Case Study 2 Production and Storage SFPE Polish Chapter Wojciech Węgrzyński, Grzegorz Krajewski Building Research Institute (ITB)

3 So What Are You We Going to Show You? A lot of tables, simplified methods etc. this is how our legal system works at the moment! Some performance engineering mainly connected with the design of SHEVS A bit of paradox when it comes to ESFR sprinklers and SHEVS, we are in quite of a trouble

4 Engineering Methods in Use, Related to Industrial Buildings Type Software / model CFD Evacuation Hand calculations FDS, ANSYS, Phoenix, Smartfire, AutodeskCFD Pathfinder, Evac, buildingexodus Popularity high high Application CFD analysis form the base of most of SHEV design, are widely used in evaluation of environmental conditions for users, Often referred as the valid method for estimation of ASET time Usually combined with CFD analysis as the method for estimation of RSET, but usually not as a part of industrial building design Fire Load Density high Requirements for industrial buildings rely on Fire Load Density, thus this element is part of every industrial design Explosion Risk high Risk of explosion will increase the requirements for the building Sizing SHEVS NFPA, PB, DIN, TR high Hand calculations are always part of the SHEVS design, and often the only dimensioning approach used

5 Engineering Methods in Use, Related to Industrial Buildings Type Software / model Popularity Application Zone Modeling CFAST, Brisk, fireplatform.eu medium Used in preliminary design, rarely part of the building design permit application Radiation modeling fireplatform.eu, FDS, ANSYS low Used in the derogation process for the possible separation between the buildings, may be used for the design of separation between storage areas in storage facility FEM FVM ANSYS, Robot low Used in structural design of some buildings (for fire conditions)

6 Tenant 1 High bay storage with 2 levels of catwalks at levels of 4 and 8 m (document archive), additional office mezzanine above loading bay Tenant 2 High bay storage with man-up system (car parts warehouse) Tenant 3 Production of furniture with raw material storage and ready products storage, 2 floor office building

7 Estimation of Fire Load Density Fire load density is a key parameter in determination of safety requirements for industrial buildings The most popular methods for estimation of the fire load density are inventory methods involving survey of fire materials in a building. Such methods require an estimation of the amount of each flammable material, that adds up to the sum of fire load within the area It is uncommon in Poland to use performance engineering or more advanced fire load estimation methods (ie. NFPA 557) Qd fire load density [MJ/m2] Qci x Gi Heat of combustion x mass F - Area

8 Estimation of Fire Load Density tenant 1 tenant 2 tenant 3 Type Storage/Archive High storage car parts (plastics?) Medium storage, production Materials Paper, evenly packed in closed Metals (20%), plastics (PE - 25%, PCV 25%), foams (PU) (30%) Multplier 0,2 - - Heat of combustion [MJ/kg] 16 24,25 19,85 Estimated mass Fire Load Density approx t of paper 312 MJ/m² Q < 500 MJ/m² approx. mass of t of stored goods MJ/m² Q > 4000 MJ/m² Wood (30%) and cellulose materials (15%), upholstery (15%) packaged goods (40%) 105 t of stored materials 15 t of goods in the production line 324 t of stored goods MJ/m² 1000 MJ/m² < Q < 2000 MJ/m²

9 Fire Risk Classes of the Building If sprinklers are used risk class E relating to lowest requirements If no sprinklers or SHEVS are used: tenant 1 class E tenant 2 class A tenant 3 class C

10 Fire Resistance Building risk class Main structure of the building Required fire resistance class for structure elements roof structure roof external walls internal walls roof covering "A" R 240 R 30 REI 120 EI 120(o i) EI 60 RE 30 "C" R 60 R 15 REI 60 EI 30 (o i) EI 154) RE 15 "E" (-) (-) (-) (-) (-) (-) Class A and C give requirements so high for an industrial building, that it is not economically reasonable to not use sprinklers!

11 Fire Zone Area Allowed Fire load Q > < Q Q 500 Maximum area of the fire zone (single floor building) basic + SHEVS + Sprinkler + Sprinkler + SHEVS unlimited unlimited unlimited

12 Separation Distances Distance between buildings of given classes Human occupation (ie. office) Human occupation (ie. office) Livestock building Production/storage Q < Q Q > Livestock building Production/storage Q Production/storage < Q Production/storage Q >

13 Evacuation From any point in the building to an exit to an evacuation route, other fire zone or outside of the building, from 100 to 175 m (dependant on choice of fire protection features) Length of evacuation route (corridors, staircases etc.): Type of fire zone single direction Length of evacuation route shortest route, when two directions or more are available (length for 2nd direction) Industrial, Q > 500 MJ/m² 30* 60 (120) Industrial, Q < 500 MJ/m² 60* 100 (200) ZL III (offices) 30* 60 (120) * not more than 20 m on a horizontal route

14 Potential Problem Office above Loading Bay Real solution in Poland the legal downside of an office within industrial fire zone is too big for any investor to allow it simpler solution is to move this part into other building

15 Potential Problem Separation Distance in Unsprinklered Zone (Tenant 1) 5 MW 10 MW

16 Potential Problem Max. Area of the Fire Zone, Tenant 2

17 Potential Problem Functional Separation of Smoke Zones in Tenant 3 Zone as a Protection for Fragile Production Equipment a Need for a Shevs Overdesign

18 The Main Use of Performance Engineering in Poland Design of Smoke and Heat Exhaust System

19 Design example the design of NSHEV system of the tenant 1 zone. The goal is to allow safe evacuation, limit the spread of fire and the damage done to the archive, and allow rescue operations.

20 There are mezzanine levels in the zone, so the evacuation from top tier (+8,00 m) must be possible. The office must be separated from the smoke zone of archive, by at least a smoke curtain.

21 Standard approach PN-B Max area of smoke zone 2 600m² Min. Height of smoke curtain 3,075 m, which makes smoke free height of ~ 9,00 m (does not guarantee safe evacuation!)

22 Aerodynamic area of smoke ventilators in each smoke zone 1,50% of the zone area, which relates to 39 m²

23 Mass density of smoke (0,00 0,20 g/m3) t = 10 min, 5 MW fire Temperature ( K) t = 10 min, 5 MW fire

24 Mass density of smoke (0,00 0,20 g/m3) t = 10 min, 10 MW fire Temperature ( K) t = 10 min, 10 MW fire

25 Replacing PN-B approach with NFPA 204. The fire for an archive may be considered as slow. The calculated aerodynamic free area of the ventilators is 39,6 m²

26 Mass density of smoke (0,00 0,20 g/m3) t = 10 min, 5 MW fire Temperature ( K) t = 10 min, 5 MW fire

27 Mass density of smoke (0,00 0,20 g/m3) t = 10 min, 5 MW fire Temperature ( K) t = 10 min, 5 MW fire

28 Can We Further Optimize the System with Computational Fluid Dynamics Tools? The search for the minimum area of ventilators

29 Mass density of smoke (0,00 0,20 g/m3) t = 10 min, 5 MW fire Temperature ( K) t = 10 min, 5 MW fire

30 Mass density of smoke (0,00 0,20 g/m3) t = 10 min, 10 MW fire Temperature ( K) t = 10 min, 10 MW fire

31 What about the Adverse Influence of Wind on the System Performance?

32 Combined wind and fire analysis: 1. Wind coefficient analysis 2. Fire performance of NSHEV 3. Optimization

33 Wind pressure coefficient, for Uref = 4,67 m/s, at Zref = 10 m

34 Wind pressure coefficient, for Uref = 10,00 m/s, at Zref = 10 m

35 HRR = 5 MW, α = 135, A = 26 m² for Uref = 1,0 m/s for Uref = 4,67 m/s for Uref = 10,0 m/s

36 HRR = 10 MW, α = 135, A = 26 m² for Uref = 1,0 m/s for Uref = 4,67 m/s for Uref = 10,0 m/s

37 Real Application Example

38 Tenant 2 the Problems with ESFR Sprinklers and SHEVS

39 Issue with ESFR Sprinklers and Ventilation For the benefits shown in the beginning of the presentation, combination of SHEVS and sprinklers is required SHEVS system has to be automatic (by law), while most standards require SHEVS in manual control ie. automatic solution is not allowed by VdS 2815 : Solution is to provide high-temperature actuators (140 C, 182 C) for the ventilator, that allow sprinklers to operate long before the SHEVS, but at the same time, if for some case sprinklers do not actuate, the SHEVS system can

40 120 s, HRR = 2701 kw 180 s, HRR = 6078 kw 240 s, HRR = kw

41 Temperature ( C) H = 11,00 m 180 s, HRR = 6078 kw 240 s, HRR = kw

42 Mass density of smoke at the time of firefighter approach (t = 600 s) Required free area of ventilators for smoke clearence less than 10 m²

43 Thank You for Your Attention!