There are different types of damper for smoke we use fire damper with smoke sensor inside the space. For pressure relief we use motorized damper with PT(pressure transducer) inside the duct when ever pressure increases above the set pressure PT sense the pressure and open the motorized damper to relief the pressure
Thank you for the informative video, I have a question for a case there is a pressurized smoke stop lobby before the staircase. How would the pressure difference be calculated assuming that the pressure difference bet. the smoke stop lobby and the corridor is 25 Pa
Pressure difference can be calculated, that how much air is in and how much air is out. In staircase the pressure is positive but in lobby the pressure will be negative for smoke extraction.
Hi. It was a concise explanation for the stairwell pressurization calculation's. Can you share to me the excel table shown? Thanks in advance and would appreciate it much.
Nice explanation. Thanks alot. Can you please explain on below. 1. Here in this example there is only 1 no. door on each floor but you have considered A1 and A2 which means 2 nos. of doors. This is just for example only or we have to consider A1 and A2 always for 1 door per floor. If not then can we put A2 as Zero. 2. You have considered A1 and A2 in parallel. This is also for example or we have to consider it this way in case of single door. As per my understanding, doors in series means one door besides other door and parallel means 2 doors in front of each other. Can you please explain as I am new to this.
As far as I know Parallel and Series means we have to consider the flow path. If same amount of air [or any physical quantity] passes through the doors in one path they are in series, else parallel. Thank you!
If you have 3 fire exist than you have to select 3 in excelsheet ,depending on type. Select no of floors, Excelsheet will calculate airflow rate automatically
Thank you. Good video. Do you have the calculator in the feet measuring system? We have a project where the engineer put a static pressure sensor in 1/3 of the stairwell height for a 9-floor building. Should it be a differential pressure transmitter? How should we choose the correct model number?
@@passionateengineer04 Thanks a lot. If the pressure range isn't provided, is there any way to figure it out besides an RFI? Couldn't find a link to the software.
I want to know the sizing of ducts.. we do it like fixed losses like HVAC system design!! And I want to know the velocity of air in the duct 1600 FPM or what ?
One is velocity method and one is equal friction method, in velocity we consider standard velocity for sizing of duct and in equal friction method we select 0.08 wc/100 feet and 0.04 for return air duct.
Hi Bros ! Are you able to make a calculation sheet for ESP of the fan (of course a fan need flow/esp). I wonder why you plus air flow of leakage and air flow through the doors opened, because when any door open, pressure will become zero? And please advise how you estimate of the relief air requirement ? Thank you !
In staircase pressurization you have to consider these parameters, you must set the pressure behind the door and in staircase. When door opens the pressure in staircase and room will be equal.
@@passionateengineer04 I believe that operation of pressurization fan in a protected stair case is much different with an AHU, because it have some scenarios like when all door closed (minimum flow), when 3 doors open (maximum design flow). As well as "available static pressure" in the staircase.
The design is base on your requirements like one door is open you will required high flow so need to design for this flow rate and ESP. You have to use VFD drive fan with pressure sensor in stair to maintained that pressure and when door closes the flow reduces to avoid back pressure in duct.
It doesn't need exhaust fan, it needs relief dampers, with smoke detector give signal to staircase pressurization than it starts to pressurize staircase and exceeding pressurize is relief through relief dampers. Smoke extraction fan have different criteria
@@passionateengineer04 thank you for your reply. But the string values are shown immediately as I open the downloaded file. Meaning I didn't wrote any numbers, values etc. In your example I see that decimals are divided by dot, but when I open the file decimals are divided by comma. Don't know if this makes any reason. But also, line 16, drop down menu, I can't change from dot to comma (to see if comma is the problem).
Dear sir nice video , but when does we require to install stair case pressurization system and smoke extraction system , I mean is there minimum area requirements or minimum ht of building or no of floor given in nfpa
There is requirement of distance between the start of building and exit door or mean of escape as per NFPA. Like for office building when distance between start of office where person is seated and emergency exist stair is greater than 61 meter than you have to install smoke extraction fan and there is hight requirement for different type of building like building height is greater than 75 feet required staircase pressurization system.
In outer space pressure will be atmospheric pressure but the difference should be maintained at 12.5 Pa for sprinklered buildings. However, the pressure in staircases should not exceed the threshold at which the force required to open doors exceeds 30 lbf.
for Q2, we have considered the effective open doors area for one floor 5.82m2 with 1.02m/s velocity that comes out to be 5940 l/s. why don't we multiply this value with the number of floors (i.e. 5)?
How do you calculate the maximum relief air design flow rate? It must be the sum of the injection airflows minus the natural leakage rate (through gaps)? So, in this example it should be 7106l/s-520l/s=6586l/s? Why does row number 53 indicate relief air is 5420?
Determine the heat release, smoke mass flow rate, you have to calculate smoke temperature and put it in equation to calculate air flow rate and than fan static pressure. I will make a video on this topic.
In design you have to set pressure behind the door and in staircase for example behind the door pressure is 302 pa and staircase is at 200 pascal so PD will be 102 pa. During air balancing you have to maintain that PD.
In UAE all ducts related to basements parking, makeup air unit, smoke extraction, staircase pressrization are fire rated. But you can also confirm from local code ie municipality etc.
This Excel is not giving any results except Default Capacity which is 7106 l/s. I have tried to put my project values but Final Values is not changing...Please Help
@@passionateengineer04 Sir, I have input values until Door A1 and A2. Kept 25N and changed all the figures which has to be input... Trust me it is giving me same result...Please can u cross check it the excel file which you attached in the download link... It would be a great help for Me...Thanks
Thank you for this video. I appreciate the information.
thank you so much , this is very helpful specially for all those who are new in field
Very good Explanation, thank you very much sir. GOD bless you.
Very well described the staircase pressurization system with details, it's really helpful.
Great job. That was useful
Thank you.
Thank you I'm watching you from Saudi Arabia +1
thanks for the free resources❤ and for that, a new sub & a like. keep it up bro!
Thank u sir....Very useful
thank you sir
Download Excel sheet using the link in video discription.
Great.. keep going
You presented very rare calculation sheet. Practically not even in one percent of buildings this kind of calculation is done.
We have practically done this in UAE and KSA.
Calculations are same but senario can be different.
Sir please upload one video of coil calculation of ahu and also dehumidified air calculation please upload sir
Great video, I would like to ask whether volume damper is required for air balancing on each floor landing or no need for Air Balancing???
VCD is required for every branch where air terminals are Installed for air balancing
Can you please explain more about pressure relief damper and how it will operate at fire conditions?
There are different types of damper for smoke we use fire damper with smoke sensor inside the space. For pressure relief we use motorized damper with PT(pressure transducer) inside the duct when ever pressure increases above the set pressure PT sense the pressure and open the motorized damper to relief the pressure
Thanks, can you please share the excel sheet?
Thank you for the informative video, I have a question for a case there is a pressurized smoke stop lobby before the staircase. How would the pressure difference be calculated assuming that the pressure difference bet. the smoke stop lobby and the corridor is 25 Pa
Pressure difference can be calculated, that how much air is in and how much air is out.
In staircase the pressure is positive but in lobby the pressure will be negative for smoke extraction.
Thanks you for your video and explanation. Which flow that we use to select fan? Relief Air requirement or Stair Pressurization Air flow?
Its for selection of pressurisation fan.
@@passionateengineer04 Stair Pressurization air flow rate?
The cfm calculated in excelsheet are staircase pressurisation flow rate.
Is it required to add additional pascal while doing ESP for pressurization fan?
You add some factor of safety, if you are not 100% sure.
Hi. It was a concise explanation for the stairwell pressurization calculation's. Can you share to me the excel table shown? Thanks in advance and would appreciate it much.
You can find it in video description
Nice explanation. Thanks alot.
Can you please explain on below.
1. Here in this example there is only 1 no. door on each floor but you have considered A1 and A2 which means 2 nos. of doors. This is just for example only or we have to consider A1 and A2 always for 1 door per floor. If not then can we put A2 as Zero.
2. You have considered A1 and A2 in parallel. This is also for example or we have to consider it this way in case of single door.
As per my understanding, doors in series means one door besides other door and parallel means 2 doors in front of each other. Can you please explain as I am new to this.
Standard staircase have maximum of two doors but it can be one depend upon on your building. If you have 1 door than choose one only.
@@passionateengineer04 Ok. Thank you.
As far as I know Parallel and Series means we have to consider the flow path. If same amount of air [or any physical quantity] passes through the doors in one path they are in series, else parallel. Thank you!
How do we get the door closing force. Do we have to ask this to the door supplier or just consider 25N as standard.
It depends on size of door but you can use 25N for standard doors
@@passionateengineer04 Thank you.
Do you only calculate air volume, and not pressure needed for air flow to reach the bottom flor?
These air flow is based on standard pressure as per IBC and need to maintain maximum pressure of 90 pascal, so the door opening force doesn't exceed.
Hi, about the Stair Pressurization Flow Rate result, will i divide the results into 3 if the building has 3 Fire Exits?
If you have 3 fire exist than you have to select 3 in excelsheet ,depending on type.
Select no of floors,
Excelsheet will calculate airflow rate automatically
Calculations are based upon leakage area
Thank you. Good video. Do you have the calculator in the feet measuring system? We have a project where the engineer put a static pressure sensor in 1/3 of the stairwell height for a 9-floor building. Should it be a differential pressure transmitter? How should we choose the correct model number?
Please check my other video regarding the calculation, yes it shall be PDT, you can choose the correct model based on pressure range.
@@passionateengineer04 Thanks a lot. If the pressure range isn't provided, is there any way to figure it out besides an RFI? Couldn't find a link to the software.
How do you calculate the pressure difference between the Indoor space and staircase space. Or is there any standard for that.
Its the standard pressure difference between staircase and building space, so when staircase is pressurized such difference will be achieve.
@@passionateengineer04 Thanks for replying.
I want to know the sizing of ducts.. we do it like fixed losses like HVAC system design!! And I want to know the velocity of air in the duct 1600 FPM or what ?
One is velocity method and one is equal friction method, in velocity we consider standard velocity for sizing of duct and in equal friction method we select 0.08 wc/100 feet and 0.04 for return air duct.
Sir i want this excel sheet
Hi Bros ! Are you able to make a calculation sheet for ESP of the fan (of course a fan need flow/esp). I wonder why you plus air flow of leakage and air flow through the doors opened, because when any door open, pressure will become zero? And please advise how you estimate of the relief air requirement ? Thank you !
Watch this video for ESP calculation.
czcams.com/video/YfNvhDtlJ4Y/video.html
In staircase pressurization you have to consider these parameters, you must set the pressure behind the door and in staircase. When door opens the pressure in staircase and room will be equal.
@@passionateengineer04 I believe that operation of pressurization fan in a protected stair case is much different with an AHU, because it have some scenarios like when all door closed (minimum flow), when 3 doors open (maximum design flow). As well as "available static pressure" in the staircase.
Do you want to control the air flow? When you required high and when required low? But you have to design it for worst case senerio.
The design is base on your requirements like one door is open you will required high flow so need to design for this flow rate and ESP.
You have to use VFD drive fan with pressure sensor in stair to maintained that pressure and when door closes the flow reduces to avoid back pressure in duct.
Why you selected 25N as the door closer force?, Is there any reference for selecting the door closer force
czcams.com/video/X4F3zaObatQ/video.html
Check the video description there is excelsheet, in which you can find the reference.
It NFPA.
Thank You. Supply air fan is 7106 LPS . What about exhaust fans capacity? Can I assume it is 80% that of Supply fan?
It doesn't need exhaust fan, it needs relief dampers, with smoke detector give signal to staircase pressurization than it starts to pressurize staircase and exceeding pressurize is relief through relief dampers.
Smoke extraction fan have different criteria
@@passionateengineer04 🙏👍
Greetings! I don't know why I get those #VALUE! strings in calculations section rows. Any idea? Thank you!
May be you put something other than numbers.
@@passionateengineer04 thank you for your reply. But the string values are shown immediately as I open the downloaded file. Meaning I didn't wrote any numbers, values etc. In your example I see that decimals are divided by dot, but when I open the file decimals are divided by comma. Don't know if this makes any reason. But also, line 16, drop down menu, I can't change from dot to comma (to see if comma is the problem).
Dear sir nice video , but when does we require to install stair case pressurization system and smoke extraction system , I mean is there minimum area requirements or minimum ht of building or no of floor given in nfpa
There is requirement of distance between the start of building and exit door or mean of escape as per NFPA.
Like for office building when distance between start of office where person is seated and emergency exist stair is greater than 61 meter than you have to install smoke extraction fan and there is hight requirement for different type of building like building height is greater than 75 feet required staircase pressurization system.
@@passionateengineer04 thank you sir for your reply
If pressure difference across staircase and outer space is 12 .4 Pa then what would be the pressure on inside the staircase and outer space
In outer space pressure will be atmospheric pressure but the difference should be maintained at 12.5 Pa for sprinklered buildings. However, the pressure in staircases should not exceed the threshold at which the force required to open doors exceeds 30 lbf.
for Q2, we have considered the effective open doors area for one floor 5.82m2 with 1.02m/s velocity that comes out to be 5940 l/s. why don't we multiply this value with the number of floors (i.e. 5)?
Its just an example, it depends on no of floors and no of doors per floor.
@@passionateengineer04 got it, but the point i want to clear is that will we multiply the Q2 with number of floors?
Check no 5 effective area of 3 open doors, it for 3 doors. Mean each door per floor
how do you size the fan pressure after getting the flow rate
Calculate the ESP, once you get that, you can select fan on the basis of ESP and flow rate.
@@passionateengineer04 my question was do you have a detailed video on how to calculate esp, I watched one but it wasnt clear enough
@@jacksonkilonzo3531 czcams.com/video/YfNvhDtlJ4Y/video.html
How do you calculate the maximum relief air design flow rate? It must be the sum of the injection airflows minus the natural leakage rate (through gaps)? So, in this example it should be 7106l/s-520l/s=6586l/s? Why does row number 53 indicate relief air is 5420?
Total air flow required for staircase - air flow passing through doors when doors are open.
Thank you
Hai, How 3 nos. of door opening has been considered ?? Could you please provide us code reference for the same?
Its standard 3 nos doors are considered, check NFPA or ASHRAE.
@@passionateengineer04 Thanks for your reply. I checked with NFPA 92 but the same was not mentioned. Could you please specify the clause from NFPA.
How to design exhaust fan for stairwell system?
Determine the heat release, smoke mass flow rate, you have to calculate smoke temperature and put it in equation to calculate air flow rate and than fan static pressure. I will make a video on this topic.
@@passionateengineer04 tq sm waiting for video
Can i ask for a electronic copy of this, thank you
Can you please check Description of video? link is there
Hello Can I ask for a electronic copy, thank you
Link is in description
Could you explain how calculate Pressure difference across doors (must not exceed values listed below A1=102Pa,A2=(92Pa)
In design you have to set pressure behind the door and in staircase for example behind the door pressure is 302 pa and staircase is at 200 pascal so PD will be 102 pa. During air balancing you have to maintain that PD.
@@passionateengineer04 Can you send not lock exel calculation
Smoke extraction system on shopping mall pls
Sure in next video
@@passionateengineer04 thank you
Air Flow through the leaks ,Q=0.827XA X(P)1/2 ,How to calculate Area
Lengthxwidth or diameter of leak to calculate area, you can use thumb rule or use standard leak cfm.
Which type of duct used in staircase pressurization... GI or fire rated duct ? Kindly reply
GI can be used with fire damper at penetration.
Better to use fire rated duct if possible.
Refer to local code or AHJ.
Engr. please tell which one is mostly used in UAE
In UAE all ducts related to basements parking, makeup air unit, smoke extraction, staircase pressrization are fire rated.
But you can also confirm from local code ie municipality etc.
@@passionateengineer04 Should i prefer Coated or non-coated fire rated ducts for smoke extraction?
This Excel is not giving any results except Default Capacity which is 7106 l/s. I have tried to put my project values but Final Values is not changing...Please Help
You may doing some mistake, check all inputs.
Thanks
@@passionateengineer04 Sir, I have input values until Door A1 and A2. Kept 25N and changed all the figures which has to be input... Trust me it is giving me same result...Please can u cross check it the excel file which you attached in the download link... It would be a great help for Me...Thanks
Ok let me check this one.
Kindy share your email, i will send you another file.
@@passionateengineer04 It is not allowing me to post my Email address here
Search my channel and go to contact section, there is my email.
sir please share excel format
Please check the description
whats the password ?
1234
Its not wroking
Open the link and check it, its above the a another link
1234@@passionateengineer04