Stair Case Pressurization Calculation - Class A

Calculation for Stair case pressurization System . ST-1 & 2 CLASS A SYSTEM Case-1 ; Considering only leakage through the Door at the ST-1 area Double Door area ( only at Ground floor) Height-H/(m) = Width-D/(m) = Total No of Door = Total Area = Leakage factor for Double Door is , K Air Flow rate Q , as per BS 5588 Q=0.83xAxP^0.5 Q=0.83x(1X0.03)x50^0.5

2.2 2.2 1 4.84 0.03

m m Nos m2

3

Q1 0.18 m /s Single Door Area (all the floor apart from Ground Floor ) Height-H/(m) = 2.2 m Width-D/(m) = 1.1 m Total No of Door = 29 Nos 2 Total Area = 70.18 m Leakage factor for single Door is , K 0.01 Air Flow rate Q , as per BS 5588 Q=0.83xAxP^0.5 Q=0.83x(29X0.01)x50^0.5 3 Q2 1.70 m /s Total Air Flow rate for ST-01 Q3 = Q1+Q2 m3/s Q3 = 0.18+1.7 3 1.88 m /s 3,980.66 cfm 3 Increase by 50% 2.82 m /s Q3 = 5,970.99 cfm Case-2 ; Considering one single door is opened (Class A system) Single Door Area Height-H/(m) Width-D/(m)

= =

Total area A = From the BS5588 ,velocity is to be 0.75m/s

2.2 m 1.1 m 2.42 sqm V = 0.75 Q4= AV Q4= 2.42X0.75 Q4= 1.815 3,846.97

m/s m3/s m3/s cfm

Total of case 1 & Case 2 Q= Q3+Q4 3 Q= 2.82+1.815 m /s 3 Q= 4.63 m /s 9,818 cfm

Total Volume Flow Rate Add Duct leakages @ 15%

9,817.96 cfm 3 0.69 m /s 1,472.69 cfm 3 Total Volume Flow Rate of the Fan should be 5.33 m /s 11,290.65 cfm According to the BS 5588 Staircase pressurization fan is to be single speed 1hr fire rating @300C a) To calculate pressure required in stairwell to exhaust 1.815 m3/s to atmosphere via fire floor Area of single leaf door=2.2X1.1=2.42 sq.m Area of exhaust vent = 1.815/2.5 =0.726 sq.m A.E = (1/A1^2+1/A2^2)^-0.5 = (1/2.42^2+1/0.726^2)^-0.5 = 0.70 sq.m P1=(Q/(0.83XA.E))^2 = (1.815/(0.83X0.7))^2 = 9.758902835 Pa This is more than covered by 50 Pa b) To calculate area of pressure relief Quantity of air to be wasted = 5.33 - 2.82 3 = 2.51 m /s Area of pressure relief = Q/(0.83XP^0.5) = 2.51 / (0.83X50^0.5) = 0.428 sq.m Let Height of Pressure relief damper = 0.7 m then Width will be = 0.428 / 0.7 = 0.62 m, say 0.65m

FAN SELECTED IS 11,300 CFM @ 240 PA

Static Pressure Calculations Note:1) The Equivalent Diameter Formula is: De = 1.3(ab)^0.625 / (a+b)^0.25 2) The friction loss and the velocity can be obtained from the charts knowing the flow and the eq. diameter 3) The equivalent length for an elbow can be obtained from the formula: Le = W exp [-2.13(H/W)^0.126 ln(0.33R/W)]

ST-01 & 02 - Presurization unit (11310cfm)@237Pa Straight Ducts

Width/(mm) 1600 1550 1500 1450 1400 1350 1300 1250 1200 1150 1100 1050 1000 950 900 850 800 750 700 650 600 550 500 450 400 350 300 250 500 350

Height/(mm) 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 500 200 200

Volume flow Rate/(cfm) 11,310.00 10,933.00 10,556.00 10,179.00 9,802.00 9,425.00 9,048.00 8,671.00 8,294.00 7,917.00 7,540.00 7,163.00 6,786.00 6,409.00 6,032.00 5,655.00 5,278.00 4,901.00 4,524.00 4,147.00 3,770.00 3,393.00 3,016.00 2,639.00 2,262.00 1,885.00 1,508.00 1,131.00 754.00 377.00

Length(m) 10 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 10 8

54 Fittings Size Elbow 1600x500 Reducer

Qty 2 29

Eq. length (m) 3 1.0

Friction Loss (Pa) 4.0 19.1

Eq. Diameter(De) m 0.939 0.926 0.913 0.900 0.886 0.872 0.857 0.843 0.827 0.812 0.795 0.779 0.762 0.744 0.726 0.706 0.687 0.666 0.644 0.622 0.598 0.573 0.547 0.518 0.488 0.455 0.420 0.381 0.337 0.286

SAT(sound attonuator) VAV Flexible duct

Fire Damper Size

0 0 0

0.3inch/100ft sub total

70 0 0.00 89.14

Pressure Drop (Pa) 0

VCD Size Various

Qty

grilles Various

Qty

Preassure Drop (Pa) Additional 20%

2

Avg Pressure Drop/(Pa) 20

1

Avg Pressure Drop/(Pa) 10

197.20 Pa 39.44 Pa

Total pressure Drop accros the exhaust air side of FAHU-1 unite

237 pa

^0.126 ln(0.33R/W)]

Friction loss pa/m

inch/100ft

0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57 0.57

0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07

TOTAL

Total Friction Loss(Pa) 5.740 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 2.296 5.740 4.592

78.064

Calculation for Stair case pressurization System . ST-3 to 7 CLASS A SYSTEM Case-1 ; Considering only leakage through the single Door at the ST-3 area Double Door area ( only at Ground floor) Height-H/(m) = 2.2 m Width-D/(m) = 2.2 m Total No of Door = 1 Nos 2 Total Area = 4.84 m Leakage factor for Double Door is , K 0.03 Air Flow rate Q , as per BS 5588 Q=0.83xAxP^0.5 Q1 =0.83X(1X0.03)X50^0.5 3 Q1 0.18 m /s Single Door Area (all the floor apart from Ground Floor ) Height-H/(m) = 2.2 m Width-D/(m) = 1.1 m Total No of Door = 6 Nos 2 Total Area = 14.52 m Leakage factor for single Door is , K 0.01 Air Flow rate Q , as per BS 5588 Q=0.83xAxP^0.5 Q2=0.83X(4X0.01)X50^0.5 3 Q2= 0.35 m /s Total Air Flow rate for ST-01 Q3 = Q1+Q2 3 Q3 = 0.18+0.35 m /s 3 0.53 m /s 1,119.56 cfm 3 Increase by 50% 0.79 m /s 1,679.34 cfm Case-2 ; Considering one single door is opened (Class A system) Single Door Area Height-H/(m) Width-D/(m)

= =

Total area A = From the BS5588 ,velocity is to be 0.75m/s

2.2 m 1.1 m 2.42 sqm V = 0.75 Q4= AV Q4= 2.42X0.75 Q4= 1.815 3846.97

m/s m3/s m3/s cfm

Total of case 1 & Case 2

Total Volume Flow Rate of the Fan should be Add duct losses @ 15%

Q= Q3+Q4 Q= 0.62+1.815 Q= 2.607 Q= 5,526 5,526.31 0.39 828.95

m3/s m3/s cfm cfm m3/s cfm

3

3.00 m /s 6,355.26 cfm According to the BS 5588 Staircase pressurization fan is to be single speed 1hr fire rating @300C Total Volume Flow Rate of the Fan should be

a) To calculate pressure required in stairwell to exhaust 1.815 m3/s to atmosphere via fire floor Area of single leaf door=2.2X1.1=2.42 sq.m Area of exhaust vent = 1.815/2.5 =0.726 sq.m A.E = (1/A1^2+1/A2^2)^-0.5 = (1/2.42^2+1/0.726^2)^-0.5 = 0.70 sq.m P1=(Q/(0.83XA.E))^2 = (1.815/(0.83X0.7))^2 = 9.758902835 Pa This is more than covered by 50 Pa b) To calculate area of pressure relief Quantity of air to be wasted = 2.80 - 0.62 3 = 2.18 m /s Area of pressure relief = Q/(0.83XP^0.5) = 2.18 / (0.83X50^0.5) = 0.371 sq.m Let Height of Pressure relief damper = 0.5 m then Width will be = 0.371 / 0.5 = 0.742 m, say 0.75m

FAN SELECTED IS 6400 CFM @ 150 PA

Static Pressure Calculations Note:1) The Equivalent Diameter Formula is: De = 1.3(ab)^0.625 / (a+b)^0.25 2) The friction loss and the velocity can be obtained from the charts knowing the flow and the eq. diameter 3) The equivalent length for an elbow can be obtained from the formula: Le = W exp [-2.13(H/W)^0.126 ln(0.33R/W)]

ST-3 TO 7 - Presurization unit (6356cfm)@148Pa Straight Ducts

Width/(mm) 750 650 650 550 450 350 350

Volume flow Rate/(cfm)

Height/(mm) 650 650 550 550 550 550 350

Length(m) 10 4 4 4 4 4 4 34

6,356.00 5,448.00 4,540.00 3,632.00 2,724.00 1,816.00 908.00

Eq. Diameter(De) m 0.763 0.711 0.653 0.601 0.543 0.477 0.383

Fittings Size Elbow 2100x1100 Reducer

Qty 2 6

SAT(sound attonuator) VAV Flexible duct

0 0 0

Fire Damper Size

Friction Loss (Pa) 4.0 4.0

0.3inch/100ft sub total

70 0 0.00 73.96

Pressure Drop (Pa) 0

0

VCD Size Various

Qty

grilles Various

Qty

Preassure Drop (Pa) Additional 20%

Eq. length (m) 3 1.0

2

Avg Pressure Drop/(Pa) 20

1

Avg Pressure Drop/(Pa) 10

123.48 Pa 24.70 Pa

Total pressure Drop accros the exhaust air side of FAN-ST-1 unite

148 pa

Friction loss pa/m 0.57 0.57 0.57 0.57 0.57 0.57 0.57 TOTAL

inch/100ft 0.07 0.07 0.07 0.07 0.07 0.07 0.07

Total Friction Loss(Pa) 5.740 2.296 2.296 2.296 2.296 2.296 2.296 19.516