Thank you for making this informative video. Sir, if the fire occurs on multiple floors, then the no. of open doors wont be only 2. How many open doors we will consider then?
You're welcome, when you consider 2 doors to be open , it means that 2 doors per floor, if there are 10 floors and fire occurs at all of them then 20 doors will be opened, which is already considered in design.
@@passionateengineer04 Thank you for your quick explanation Sir. But in the calculation you considered the area of 2 doors only(21+42). Shouldn't we multiply the area(63 sq. ft) with the total no. of floors?
2 doors are considered per floor but it can be 3 depending on the mean of egress. When 2 doors are considered it means that airflow per floor or 2 doors are considered ,then per floor cfm is multiplied with a total number of floors. If you have any confusion,send me an email. Thank you
Thank you for your concern. Yeah the duct will be reduced after the reduction of cfm. You can change size after cfm is reduced but try to not use more reducers because of the installation problems in the shaft. In our case the shaft is very tight to work there, so we avoid reducers and also because of the grill sizes.
Area of Floor & Ceiling =L x W= 17.5 x 8.5 =148.75 sqft but in your calculation showing 297.5 sqft. can u explains how came 279.5 sqft ? Door 7x3 =21 , 20 ft will be gap length.
First of all its not 21, its 20 and its not 7x3, its (7+3)*2 (perimeter) and second is 17.5*8.5*2= 297.5, these are not like your calculations because these are not cross sectional areas.
Please first understand the concept, how to calculate the areas etc than go for the other calculations, these are not straight forward cross sectional areas, because i didn't mentioned any cross sectional area, these methods are based on NFPA and ASHRAE, all references are given in excel sheet, go through it and please don't confuse other viewers. Thank you
The staircase is open from top to bottom, if we provide a grille on every floor, it will increase the wall penetration. The register location is always at the top of the stairs in the stairwell or staircase.
Thank you Sir. NFPA 92 stated that maximum spacing is 3 floor between grilles. It did not specify why max is 3 floors. Now I understand why. "It will increase the wall penetration." You mean, it will increase the air leakage Sir?
@@nikmatic6807 if there is opening above the staircase, you can place fan directly above it, but you are using duct system than max spacing is 3 floors, you can put in every floor, but it will increase cost of wall penetration and grilles plus increase ESP.
Can you make a video for lift well pressurization for high rise buildings as per NFPA.
Please watch staircase pressurisation calculation video, it same as lift
But don't consider open doors
Nice video sir. Is there an SI unit version of the excel sheet? Thank you
Can I also get a copy of the drawing?
Share your email address please
Sorry, not available
Dear Sir, how did you get the value of 0.2 differential pressure inch w.g. for the Q2 calculation?
Its standard depends on the door opening force.
Refer NFPA and ASHRAE handbook
@@passionateengineer04 Do you have design calculation for Fire Lift Shaft pressurisation and fire fighting lobby?
@ShashiSanmukhiya yes
@@passionateengineer04 can you send me the link for the video on youtube if possible.
Please share you email
Thank you Sir. I loved your explanation. Can you please share with us the link of the excel sheet for reference. I will be grateful.
I got it from the description. You shared it already.
Can you please help me where to find the excel file ?
@@GEORGEPAPATHANASIOU-b3k go to the video description. The is there
@@GEORGEPAPATHANASIOU-b3k passionatengineer.blogspot.com/2023/03/staircase-pressurization-system-design.html
Thank you for making this informative video.
Sir, if the fire occurs on multiple floors, then the no. of open doors wont be only 2. How many open doors we will consider then?
You're welcome, when you consider 2 doors to be open , it means that 2 doors per floor, if there are 10 floors and fire occurs at all of them then 20 doors will be opened, which is already considered in design.
@@passionateengineer04 Thank you for your quick explanation Sir.
But in the calculation you considered the area of 2 doors only(21+42). Shouldn't we multiply the area(63 sq. ft) with the total no. of floors?
2 doors are considered per floor but it can be 3 depending on the mean of egress.
When 2 doors are considered it means that airflow per floor or 2 doors are considered ,then per floor cfm is multiplied with a total number of floors.
If you have any confusion,send me an email.
Thank you
@@passionateengineer04 Thankyou for your reply. I still have further queries. Can you please share your email.
like above home many floor to keep 2 fans or more is there law for that.
Regarding staircase pressurization system?
@@passionateengineer04 yes dear for staircase you keep 2 fans, like for how many story building 2 fans are required.
hi dear for linear grill selection can u make a video for that as it is lobby area of 2078 l/s.
Sure
Can you share the cad file? Thank you.
hi dear can u make a video for chilled water system,chilled water pump head calculation, pump hydraulic calculation
HI, help me with the drawing please
Why you have not reduce the duct size in the riser diagram after the grills as the cfm will be distributed after the floors....
Thank you for your concern.
Yeah the duct will be reduced after the reduction of cfm.
You can change size after cfm is reduced but try to not use more reducers because of the installation problems in the shaft.
In our case the shaft is very tight to work there, so we avoid reducers and also because of the grill sizes.
Area of Floor & Ceiling =L x W= 17.5 x 8.5 =148.75 sqft but in your calculation showing 297.5 sqft. can u explains how came 279.5 sqft ?
Door 7x3 =21 , 20 ft will be gap length.
First of all its not 21, its 20 and its not 7x3, its (7+3)*2 (perimeter) and second is 17.5*8.5*2= 297.5, these are not like your calculations because these are not cross sectional areas.
Please first understand the concept, how to calculate the areas etc than go for the other calculations, these are not straight forward cross sectional areas, because i didn't mentioned any cross sectional area, these methods are based on NFPA and ASHRAE, all references are given in excel sheet, go through it and please don't confuse other viewers.
Thank you
Sir. Why is it that the grilles or registers are not placed for every floor level? How to know the location of register?
The staircase is open from top to bottom, if we provide a grille on every floor, it will increase the wall penetration.
The register location is always at the top of the stairs in the stairwell or staircase.
Thank you Sir.
NFPA 92 stated that maximum spacing is 3 floor between grilles. It did not specify why max is 3 floors. Now I understand why.
"It will increase the wall penetration." You mean, it will increase the air leakage Sir?
@@nikmatic6807 if there is opening above the staircase, you can place fan directly above it, but you are using duct system than max spacing is 3 floors, you can put in every floor, but it will increase cost of wall penetration and grilles plus increase ESP.
@@passionateengineer04 What is ESP Sir?
@@nikmatic6807 External static pressure of fan.
HI dear can i have this drawing,
Share your email please