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Fire Protection Analysis: Dell Academic Building
Culminating Experience ProjectFPE 596David Gramlich
Agenda• Applicable Codes and Standards• Building Overview• Occupancy Classification• Construction Type• Structural Requirements• Emergency Power• Occupant Loading• Fire Alarm• Fire Protection• Performance Based Design: Egress Analysis• Performance Based Design: FDS Modeling• Questions
Applicable Codes and Standards
• Life Safety Code, NFPA 101, 2012 Edition (LSC)• International Building Code, 2012 Edition (IBC)• University of Texas System’s Owner’s Design
Guidelines (UT Design)• University of Texas Austin Construction
Standards (UT Standards)
Dell Academic Building
Dell Academic Building
Dell Academic Building Site Plan
Dell Academic Building Interior
Building Overview• Analysis performed at a “snapshot” of 95% Design
Development Stage (DD) (Building currently in CD Phase)
• 6 story medical administration and classroom building Square Footage:▫ Level 1: 15,611 sq.ft. ▫ Level 1.5: 4,572 sq.ft.▫ Level 2: 15,228 sq.ft. ▫ Level 3: 15,537 sq.ft. ▫ Level 4: 15,421 sq.ft. ▫ Level 5: 13,530 sq.ft. ▫ Penthouse: 7,617 sq.ft.
• Building contains 5 story Atrium• Fully sprinklered• Mixed use non-separated
Occupancy Classification• Assembly▫ Group A-2 (IBC §303.1)▫ Assembly (LSC §6.1.2.1)
• Business ▫ Group B (IBC §304.1)▫ Business (LSC §6.1.11.1)
• Storage ▫ Group S-2 (IBC §311.1)▫ Storage (LSC §6.1.13.1)
Construction Classification
• Minimum Construction Type:▫ Type IB (IBC Table 503) Maximum Height Allowed: 180 Feet Maximum Number of Stories: 12 Stories Maximum Allowable Area: Unlimited
▫ Type 222 is the minimum construction type per LSC § 12.1.6. However, the IBC was used.
Structural RequirementsStructural Member IBC Requirement
(IB)LSC Requirement (222)
Structural Frame 2-hours (Table 601.a) 2-hours (A.8.2.1.2)
Floors – Floor/Ceiling 2-hour (Table 601) 2-hours (A.8.2.1.2)
Roofs – Roof/Ceiling 1-hour (Table 601) 1-hour (A.8.2.1.2)
Shaft Enclosures* 2-hours (713.4) 2-hours (6.6.5.1)
Stairways* 2-hours (1009.3.1.2) 2-hours (7.1.3.2.1)
Atrium Separation** 1-hour (404.6) 1-hour (8.6.7)
Electrical Rooms with transformers > 112.5 kVa
1-hour (NFPA 70 §450.21.b)
Fire Pump Room 1-hour (NFPA 20 §5.12.1.1.2)
Fire Command Center 1-hour (§911.1.2)
*No less than the assembly penetrated**Closely spaced sprinklered glass may be used in lieu of a 1-hour fire barrier if glass forms smoke partition per IBC 404.6 Exception and LSC §8.6.7
Opening Protective RequirementsDoor Rating Requirement
IBC Requirement LSC Requirement
2-hour fire barrier 1 ½ hour (Table 716.5) 1 ½ hour (Table 8.3.4.2)
2-hour shaft 1 ½ hour (Table 716.5) 1 ½ hour (Table 8.3.4.2)
1-hour fire barrier ¾ hour (Table 716.5) ¾ hour (Table 8.3.4.2)
In lieu of fire barrier closely spaced sprinklered glass may be used. Doors in these glass barriers must be automatic-closing and must be installed in gasketed frames in a manner that the framing system does not obstruct the sprinkler protection per IBC §404.6 and LSC §8.6.7.
Emergency Power• Emergency Power required for illumination, fire
pump, smoke control system & fire alarm• Building is powered from two separate reliable
power grids in lieu of an emergency power supply system located on site.
• 1st grid is supplied from campus CUP. • 2nd grid is supplied from public grid.• Each grid independently connected to the building. • Automatic transfer switches within the switchgear
located on site transfer power between the two grids in the event of power failure.
Egress: Travel Distances
AssemblyComponent*
LSC Requirement (Table 1016.2)
Maximum AllowableTravel
250 ft.
Common Path (50 or more occupants)
20 ft.
Common Path 75 ft.
Dead End 20 ft.
*Mixed Use nonseparated; assembly maximum travel distances are used throughout these floors.
BusinessComponent
LSC Requirement (Table 1016.2)
Maximum Allowable Travel
300 ft.
Common Path 100 ft.
Dead End 50 ft.
Levels 1, 4 & 5 (Contain assembly) Levels 1.5, 2, 3 (No assembly)
Egress: Occupant Loading Factors & Egress Capacity
Use Occupant Loading Factor (OLF)
Assembly (Fixed Seating) Fixed
Assembly (Less Concentrated)
15 sq.ft./occupant net
Business 100 sq.ft./occupant gross
Kitchen **200 sq.ft./occupant gross
Storage/Mechanical **300 sq.ft./occupant gross
Locker Rooms *50 sq.ft./occupant net
Laboratories *50 sq.ft./occupant net
*OLF per LSC Table 7.3.1.2**OLF per IBC Table 1004.1.2
Egress Component Capacity (in./person)
Doors & Corridors .2
Stair .3
LSC Table 7.3.3.1
Occupant Loading Level 1
Occupant Loading Level 1Group Area (sq.ft.) OLF (sq.ft/occupant) Occupants
Fixed Seating 2225 N/A 90
Assembly 2301 15 154
Business 7552 100 86
Kitchen 325 200 2
Storage/Mech. 3209 300 15
Totals 15611 347
Component Door Width (Effective)
Capacity Factor Capacity Total Used
Door #1 136” 0.2 680 88
Door #2 68” 0.2 340 86
Door #3 34” 0.2 170 86
Door #4 68” 0.2 340 87
Totals 1530 347
Occupant Loading Level 1.5
Occupant Loading Level 1.5Group Area (sq.ft.) OLF (sq.ft/occupant) Occupants
Business 908 100 12
Storage/Mech. 3664 300 19
Totals 4572 31
Component Door Width(Effective)
Capacity Factor Capacity TotalUsed
Door #1 68” 0.2 340 21
Stair #1 44” 0.3 146 10
Stair #2 44” 0.3 146 0
Totals 632 31
Occupant Loading Level 2
Occupant Loading Level 2Group Area (sq.ft.) OLF (sq.ft/occupant) Occupants
Business 13927 100 176
Storage/Mech. 1300 300 9
Totals 15228 185
Component Stair Width(Effective)
Capacity Factor Capacity Total Used
Stair #1 44” 0.3 146 92
Stair #2 44” 0.3 146 93
Totals 292 185
Occupant Loading Level 3
Occupant Loading Level 3Group Area (sq.ft.) OLF (sq.ft/occupant) Occupants
Business 14809 100 169
Storage/Mech. 728 300 7
Totals 15537 176
Component Stair Width(Effective)
Capacity Factor Capacity Total Used
Stair #1 44” 0.3 146 88
Stair #2 44” 0.3 146 88
Totals 292 176
Occupant Loading Level 4
Occupant Loading Level 4Group Area (sq.ft.) OLF (sq.ft/occupant) Occupants
Assembly (Fixed)
769 N/A 49
Laboratories 3487 50 73
Locker Rooms 333 50 8
Business 9964 100 115
Storage/Mech. 867 300 8
Totals 15421 253
Component Stair Width(Effective)
Capacity Factor Capacity Total Used
Stair #1 44” 0.3 146 126
Stair #2 44” 0.3 146 127
Totals 292 253
Occupant Loading Level 5
Occupant Loading Level 5Group Area (sq.ft.) OLF (sq.ft/occupant) Occupants
Assembly 935 15 63
Business 12142 100 143
Storage/Mech. 453 300 4
Totals 13530 210
Component Stair Width(Effective)
Capacity Factor Capacity Total Used
Stair #1 44” 0.3 146 105
Stair #2 44” 0.3 146 105
Totals 292 210
Occupant Loading Penthouse
Occupant Loading PenthouseGroup Area (sq.ft.) OLF (sq.ft/occupant) Occupants
Business 570 100 7
Storage/Mech. 7047 300 27
Totals 7617 34
Component Stair Width (Effective)
Capacity Factor Capacity Total Used
Stair #1 44” 0.3 146 17
Stair #2 44” 0.3 146 17
Totals 292 34
Fire Alarm System Requirements• A manual fire alarm system and automatic fire detection is required
in accordance with NFPA 72 (IBC §907.2.6 & UT Design)• Manual pull stations provided within 5 ft. of exits. • Emergency Communication System (ECS) required and provided at
Fire Alarm Control Panel (FACP) (IBC 907.2.13) • Fire Department Radios to be used in lieu of Fire Fighter Phone
Jacks (UT Design Standard)• General Alarm Panel provided at building main entrance (UT Design
Standard)• Heat detection provided in Elevator Machine Room• Smoke detection must be installed in the following locations (IBC
907.2.18.1):▫ Main supply duct with fans greater than 2,000 CFM , return air
plenum, and ducts serving two or more stories▫ Mechanical and Electrical Rooms▫ Atrium (IBC 907.2.14)▫ Elevator Lobbies
Example Fire Alarm System Layout Level 1
Fire Protection Systems Code Requirements• Automatic Sprinkler System Required (IBC
903.3.1.1 & IBC §404.3)• Class 1 Combination Standpipe System provided
at floor landings (IBC 905.3.1). • Building contains two risers.• Standpipe demand: 750 gpm total demand at
100 psi (500 gpm at most remote riser & 250 gpm for the additonal riser per NFPA 14).
Atrium Sprinkler Zone• Atrium is a separate sprinkler zone from remainder
of building for smoke control system activation. • Zone separation is performed with separate
waterflow switch at riser location.• Atrium glass separation is required to be sprinklered
with closely spaced sprinklers in accordance with IBC §404.6 Exception 1 and NFPA 13 §8.15.4. Sprinklers must be within 4-12 inches off glass at intervals no greater than 6 ft on the walking side.
• Sprinklers must have a maximum RTI of 50 m½s½
(quick response) in accordance with DETACT analysis.
Sprinkler System Riser Diagram
Sprinkler System Design• Quick Response Sprinklers provided throughout
and utilize remote area reduction in accordance with NFPA 13 Figure 11.2.3.2.3.1.
Rooms Hazard Classification
Density and Remote Area
Offices & Circulation
Light Hazard .1 gpm/sq.ft. over a 945 sq.ft. design area
Mech./Elec./Storage and Labs
Ordinary Hazard (Group 1)
.15 gpm/sq.ft. over a 945 sq.ft. design area
Fire Pump Requirements• Backflow prevention accomplished with double
check valve assembly in a vault exterior to building. • Standpipe demand calculated as 784 GPM @ 164.6
psi with HASS. This exceeds estimated sprinkler demand.
• Water Supply: 84.6 PSI Static, 81.6 Residual @ 1247 GPM flow.
• 750 GPM @ 100 PSI boost fire pump required. • Fire Pump specified as electric horizontal-split case.• PRV used at pump outlet to regulate pressures
under 175 psi.
Sprinkler System One-Line Diagram
Sprinkler System & Atrium Limits 1st
Floor
Sprinkler System & Atrium Limits 2nd
Floor
Sprinkler System and Atrium Limits 3rd
Floor
Sprinkler System and Atrium Limits 4th
Floor
Sprinkler System and Atrium Limits 5th
Floor
Sprinkler System and Atrium Limits Penthouse
Performance Based Design Smoke Control System
• FDS Modeling used to support smoke control system design.
• LSC §8.6.7 requires smoke control system to maintain tenable conditions for 20 minutes or 1.5 calculated egress time whichever is greater.
• Tenable conditions must be maintained a minimum of 6 ft. above the walking surface per LSC §8.6.7 .
Timed Egress Analysis
• ASET > RSET• Tenable conditions must be provided for 1.5 x
calculated egress time or 20 minutes whichever is greater per LSC §8.6.7.
• tRSET = required safe egress time• Δtdet = detection time • Δta = alarm time • Δtpre = premovement time• Δttrav = travel time
Alarm, Detection and Premovement• (Δtdet ) The detection time is assumed to be the time for sprinkler
activation of 198 seconds (3.3 minutes). • (Δta) According to the National Fire Alarm Code, NFPA 72, 2007
edition, activation of initiating devices are required to occur within 90 seconds of a water flow (NFPA72 §5.11.2). NFPA 72 prescribes that the delay to occupant notification from the time of initiating signal is to be 10 seconds (NFPA72 §6.8.1.1). A value of 100 seconds (1.67 minutes) was used in this analysis as the delay from detection to occupant notification.
• (Δtpre ) Premovement time was estimated to be 60 seconds (1 minute) for familiar, awake, office buildings with voice communication in accordance with SFPE Handbook 4th Edition Table 3-12.2.
• Total time before occupant movement is 358 seconds (5.97 minutes).
Travel Time• Δttrav calculated utilizing SFPE 4th Edition Hand
Calculations. • Assumptions: ▫ Open stair within Atrium not utilized as portion of
means of egress.▫ All occupant walking speed to exit assumed to be 155
ft./min. (with locomotion disability SFPE Handbook 4th Edition Table 3-12.4).
▫ All occupant walking speed down stair assumed to be 212 ft./min. (disabled occupants use stair as an area of refuge).
▫ Occupants begin movement at the same time.▫ Stairs are filled simultaneously.
Maximum Travel Time to Reach Exits
Travel time evaluated at 155 ft./min.
Level Exit No. Maximum Travel Distance (ft.)
Travel Time (min.)
1
1 119 0.772 177 1.143 63 0.414 118 0.76
1.5Door 112 0.72
Stair No. 1 64 0.41
2Stair No. 1 191 1.23Stair No. 2 144 0.93
3Stair No. 1 205 1.32Stair No. 2 160 1.03
4Stair No. 1 134 0.86Stair No. 2 124 0.80
5Stair No. 1 150 0.97Stair No. 2 150 0.97
PHStair No. 1 100 0.65Stair No. 2 100 0.65
Stair #1-Exit No.4 4 36 0.23
Stair #2- Exit No. 1 1 78 .50
Passage Time through Egress Components
• Fs = (1-αD)kD• tp = P/ (FsWe)
▫ tp = time for passage in min.▫ α = 2.86 for speed in ft./min.▫ D = density in people per sq.ft. (.3 max for crush)▫ k = 275 for doorways and corridors; 212 for stairways with 7
in. risers and 11 in. treads▫ We = effective width in feet (minus 12 in. for boundary
layer)▫ Fsm = maximum value for corridors and doorways is 24
occ./min/ft; maximum value for 7/11 stairways is 18.5 occ./min/ft
Total Egress Times Ground Levels
Floor Exit No. Occupantstp -Exit Access Corridor (min)
tp -Exit Doorways
(min)
tp -Governing
Passage Time (min)
1
1 88 1.20 1.20 1.20
2 86 0.27 0.77 0.77
3 86 0.46 1.96 1.96
4 87 1.20 1.20 1.20
1.5 Door 21 0.29 0.29 .29
Queuing Locations
Total Egress Time Upper Floors• 34-inch stair discharge doors govern time
passage through stair at maximum flow of 24/person/min/ft. (44 persons/min).
Stairway Occupant Load Time To Discharge (min.)
Stair No. 1 438 9.95
Stair No. 2 430 9.77
Total Egress Analysis
Floor Exit tdet ta tpre 1.5 * (ttrav) RSET
1
1
3.3 1.67 1
1.5*(.77+1.20)=2.35 8.32
2 1.5*(1.14+.77)=2.48 8.45
3 1.5*(.41+1.96)=3.56 9.53
4 1.5*(1.20+.76)=2.56 8.53
1.5 Door 1.5*(.72+.29)=1.37 7.34
1.5-PH
S1* 1.5*(1.32+9.95+.23)=16.25 23.22S2* 1.5*(1.03+9.97+.5)=16.68 23.22
*Assume floor with largest travel time receives last priority into the stair and out of the discharge door. This is the 3rd Level.
FDS Modeling Tenability
Tenability Criteria Metric Units English Units
Visibility 10 meters 33 feet
Temperature 60°C 140°F
Toxicity (CO) 1000 ppm 1000 ppm
FDS Modeling Design Fire Scenarios
• Assumed maximum fuel loads to be graduate displays within atrium (kiosks)
• NISTIR 6030 provides data for burning of Kiosks (6.9 ft high x 13 sq.ft.)
• Burning of “open” kiosk has maximum HRR of 1750 kW per Kiosk
• Conservatively estimated as a “fast” growing fire
FDS Design Fire Scenario #1• 5.25 MW Axisymmetrical Fire (three kiosks)• “fast” growing fire• Maximum HRR to be maintained throughout
duration of model • Materials burned a conservative mixture of
plastic, wood and foam with the following properties:
Property Value
Heat of Combustion 20,000 kJ/kg
Soot Yield .05 g/g
CO Yield .05 g/g
0
1000
2000
3000
4000
5000
6000
0 200 400 600 800 1000 1200
HRR (kW)
time (s)
Design Fire Scenario #1
FDS Design Fire Scenario #2• 5.25 MW Balcony Spill Plume Condition on Level 1• DETACT Model showing sprinkler activation at
1,840 kW at 198 seconds.• DETACT: Ceiling height was set to 24.6 feet for the
first floor and RTI of the sprinkler was set at 50 m½s½.
• Assume sprinkler control but not extinguish.• HRR at sprinkler activation is to be maintained
throughout duration of model. • Same fuel properties as Scenario #1
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0 200 400 600 800 1000 1200
HRR (kW)
time (s)
Design Fire Scenario #2 & #3
Fire Design Scenario #1 & #2 Locations
Scenario #2Scenario #1
NFPA 92B Hand Calculation Estimation
Fire Design Scenario NFPA 92B HandCalculations Exhaust Rate
Fire Scenario #1 (Axisymmetrical)
370,000 CFM
Fire Scenario #2 (Balcony Spill Plume)*
335,000 CFM
*Width of the plume (W) assumed to be half the height of the ceiling (12 ft.).
FDS Model
• Modeled Exhaust CFM 710,000 (maximum due to makeup air openings)• Makeup 2,485 sq.ft. of openings (estimated 246 ft./min. through
openings)
Fire Design Scenario #1 Results
Fire Design Scenario #1 Temperature
Fire Design Scenario #1 Visibility
Fire Design Scenario #1 CO Concentration
.001 mol/mol of Carbon Monoxide = 1,000 ppm
Fire Design Scenario #1 Velocities
Fire Design Scenario #2 Results
Fire Design Scenario #2 Temperature
Fire Design Scenario #2 Visibility
FDS Design Fire Scenario #3
• Same as Scenario #2 however, the effect of placing the fire on Level 2 is observed.
• Scenario performed in order to eliminate the effect of any smoke allowed to escape makeup air opening.
• Same fuel properties as all scenarios.
Fire Design Scenario #3 Location
Fire Design Scenario #3 Results
Fire Design Scenario #3 Temperature
Fire Design Scenario #3 Visibility
Conclusions• Recommend separating corridors on Levels 2, 3,
4 & 5 from atrium to prevent smoke entrainment of those spaces.
• Egress should not be allowed down grand stair case due to increased velocities.
• Rerun scenarios in order to reduce CFM after corridors are separated.
• One of the exit stairs must discharge directly to the exterior.
Questions?