FireNet Community
FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Technical Advice => Topic started by: Willo on December 09, 2009, 11:21:33 PM
-
Not sure where I should post this but this forum seems the best bet.
The company I work for has recently done a review of existing skills which highlighted a few gaps. One of them being the design of smoke control systems for life safety purposes. I volunteered to get put through some training but have immediately come up against a brick wall. I can't find anywhere that offers such training. I am not wholly surprised as it is a fairly specialist field. Do any of you guys know of any institutions which would offer a course in smoke control system design? I have looked at the usual suspects such as the FPA, CIBSE and the Universities of Leeds and Greenwich but nothing. The Fire Service College does a two week course but I am wary as I guess it would be directed more at enforcement rather than detailed design. I have even looked at the IFE and IMechE which was a waste of time. Any other suggestions from the collective wisdom of this forum would be greatly appreciated. Even a book on such a subject would be very helpful (and, in this economic climate all that the company is likely to shell out for).
-
The Moreton Course is an excellent course and would give anybody a good grounding on the requirements of a smoke control system. i.e. The method of working out how much smoke you will need to remove, and the various methods for removing the smoke. You would end up being able to specify height and temp of any clear layer, fan size/vent size, number of vents/fans, inlet air requirements etc etc.
There is the BEng at UCLAN which will cover certain technical aspects, and there is a fire engineering degree in Leeds run by Leeds Metropolitan. (Not recommended for this purpose) There is a PGDip and MSc at Leeds Uni in fire and explosion, but none of these courses are as 'to the point' as what is on offer at moreton. I do believe that the FPA run an almost identical course to the Moreton one. For what it is worth, the MSc run at Leeds uni is run as various weeks of input, any of which you can attend even if you are not on the MSc.
Then there is also just good old self-teaching to consider if you possess the dedication. BS7974 is a hefty british standard but it shows you how to do it. BRE have released various papers on the subject, BR186, BR368, then there is CIBSE Guide E, TM19.
Once the number of fans, positioning, downstands and barriers are worked out then it is usually down to the M&E guys for the electrical detail etc.
-
I agree with Civvy - the FSC course is very good. Even tho', when I did it, it was mainly attended by Fire Safety Officers, the course was mainly the theory and getting stuck into the calculations as opposed to being enforcement biased.
-
Willo what type of buildings do you work in?
The moreton course I attended focussed very much on a few limited scenarios- warehouses and 1 and 2 storey shopping malls. It is a course that is more geared up to educating the fire safety enforcement officer in the basics so they have some confidence to attend meetings and read the basics of proposals. Theres also a lot of time taken showing you how to calculate things manually, how to use their own spreadsheed based calculation system and comparisons between different approaches by different engineers- Morgan and Law for example. I must admit a lot of it went over my head and I slept rather well, had to re-sit the exam. Then having qualified even at this basic level you would have keep using it otherwise you would forget. Thats I think why the degree option is a so much better bet because you are more likely to have a more general and long lasting understanding of the topic.
-
Hi Willo,
kurnal's right that for this stuff to stay inside your head instead of evaporating away you have to be in a position where you will use it, not every day but from time to time at least. Having said that, what most delegates at Moreton take away with them is an excellent grounding in the subject and an enduring confidence cultivated by being immersed in smoke control for two weeks. Yes, back at their desks on the Monday morning after the course the real world comes back to hit them hard and smoke control is filed away in some cupboard in the brain, but a lot of it sticks there and can be retrieved if required in the future.
But it's not a cheap course (getting on for £3k). It would be in your employer's interest to send you on it if you were dealing with such schemes on their behalf. It would be in your own interest to finance it only if you were in the business of fire engineering and would be able to recoup your money through jobs that you pick up.
The course is not aimed specifically at enforcement officers any more than any other group. Each time it is run though, it is attended mainly by enforcing FRS officers, and so this tends to give the courses a slant towards the enforcing officer's role. Having said that, if any designers or fire engineers come on the course then their point of view is catered for just as much as the enforcing officers'. Indeed, where there are delegates from different roles within the fire safety world the course is more balanced and gives attendees a more rounded perspective on the subject matter. As a non FRS delegate you would be welcomed onto the course and well catered for.
The FPA don't really do an equivalent course but have got courses that cover some of the same ground. From my personal and reasonably intimate experience of them I would judge their courses to be geared towards theory and away from practical application. It is easy to design a course from reading the theory in a book but it is more difficult to make the course relevant and pertinent for the delegates' needs if the course designers and instructors do not have practical experience of applying the principles in the real world.
University of Greenwich offer a week long course in fire modelling and this gives a good basic understanding of computational fluid dynamics (CFD) which complements the Moreton smoke control course well. Greenwich course is about £1k. And you cannot realistically operate in the world of smoke control with a grasp of CFD.
The thick sandwich part time course that UCLAN offer is not what it used to be I've heard. It was never great but it was reasonable. I believe you still have to attend for 8 weeks a year and I think it lasts 5 years now.
If you want a qualification out of it, you're best going for a full degree. If you want a good practical handle on the subject you're best going for the Moreton course or do as Civvy says and get reading.
You could go to www.smokeplume.co.uk and download the spreadsheet and mess around with it for a day or two. It is designed to assist you as you progress through it and you will have difficulty breaking it. Read the simple instructions on the download page, fill in the yellow boxes and see where it takes you. To understand it fully you really need the Moreton course that complements it but see how you get on.
In the new year (two years late!) this spreadsheet will evolve into an online application that will be broader in its scope and applicability whilst remaining user friendly. If you register with the site you will be notified when the new software becomes available and may be invited to be a beta tester of the new software.
Stu
-
The thick sandwich part time course that UCLAN offer is not what it used to be I've heard. It was never great but it was reasonable. I believe you still have to attend for 8 weeks a year and I think it lasts 5 years now.
UCLAN degree course is as you say is 8 weeks split into 4x2weeks block release over 4 years. it is certainly isn`t a Moreton course where you tend to be spoon fed the information. University it is very much here is some input. now go away read it and learn it. But at nearly £3,000 moreton is expensive
-
Another thing you could do....If your company is a potential customer of Colt in Hampshire then an approach to them might be beneficial.
Stu
-
Ha! Stu, I have just worked out who you are. I was at M-in-M earlier this year on the smoke control course and I do believe you were stood at the front most of the time... :)
-
You have the better of me Civvy.
I knew I should have kept my trap shut...
-
Guys,
thank you all for the information.
Kurnal, I work with many types of building from subsurface stations to office towers with a little of anything else in between when the work comes in. I already have one degree (although in Mechanical Engineering it didn't cover building services which would have helped) and am not sure if I will be able to commit to another.
Eventually I will be needing to cover both smoke extract and pressure differential systems, fan sizes, duct sizes etc. I use BR186 and BR368 which are very helpful but they only go so far in the actual design of the system, I shall have a closer look at 7976. It looks as if the self study will be the way forward for the time being with the aim of going on the Moreton Course (and meeting Stu) if there are the funds for it. I shall also have a look at your website Stu but I may wait until the New Year.
Thank you again for you time and advice.
Will
-
Willo,
Just a couple of quick points. Be careful with 186, it's very old and has some superseded methods in it. 368 is good still, ten years after publication, but there are more modern ideas in 7974. CIBSE Guide E has the advantage of being quite short and succinct - it is far from exhaustive, contains some controversial models and is disjointed, and sometimes frustrating, to work through but if you ride over these (which you can) you can get a reasonable feel for the subject quite quickly.
Stu
-
Willo, with regard the fan sizes and duct sizes, once you have calculated the volume of air needed, the fan manufacturers will have the detail of the volume that their fans shift. Unless you are working for a fan manufacturer you should not have to work out the size of a fan, but you should know the volume you need to shift, the maximum throat diameter of the fans required in order avoid 'plug-holing', and thus the actual number of fans required with an appropriate level of redundancy. All of this is taught on the Moreton course.
There is also BS7346 to consider and parts of the EN 12101 series. (12101 has a specific part for pressure differentials replacing BS5588-4) Pressure differential systems are also covered briefly on the Moreton course, and you get to actually see one working. (Unless the H&S brigade have interefered)
For info: Your degree in mechanical engineering would probably be suitable to allow you entry onto the PGDip (Post Graduate Diploma) in Fire and Explosion at Leeds University, but i think that for the money paid for the different modules of the PGDip, Moreton would end up cheaper, and it is over and done with in 2 weeks, they have beer, many "fire orientated" people to talk to, and is more specific to your needs. (But without an actual qualification at the end of it) There is also the 1 week introduction to fire engineering run from Moreton, which would be of some value with particular regard to the use of BS7974.
-
Stu, Civvy,
thanks for the pointers on the documents. I shall have a close look at all of them when I get the opportunity. If 186 has some superseded methods in it are the superseding methods explained in 7974 or another document? It might be important as we use it for some smoke calculations, on occasion to compare with our modeling software.
I shall have a look at the PDip but Moreton sounds like it will be more suitable. I'll shall try to convince the company they need to shell out that sort of money on me.
Thanks again.
Will
-
I don't know if you have had a look yet, but Stu's spreadsheet is an excellent tool for looking at smoke control right from the start of the design. Don't think that it is going to be some unusable complicated thing, it doesn't even look like a normal excel document and is littered with tips and advice.
Just playing with the spreadsheet will guide you through the process quite nicely. IMO, to use it to design a system properly then a little knowledge of the different methods (Where it asks you whether you want to use the Thomas method, Poreh et al, BRE method etc) helps, and the detail for this is given quite succinctly in BS368. Regardless of this, it will show you the process and order of how it is done.
You will also learn how to use it (The spreadsheet) on the second half of the Moreton course. Quite possibly by the spreadsheet master himself.
-
If 186 has some superseded methods in it are the superseding methods explained in 7974 or another document?
BR368 is the one that superseded 186 mainly but then 7974 has some newer stuff. Did I mention BS7346 parts 4 and 5, they're definitely worth a little look. Remember, none of these publications are "Bibles." They all have errors in them, some trivial, some more significant. That's why you have to look across the range of them to get the best picture (I almost put "true" picture, but that would have been over optimistic).
Stu
-
I haven't had the opportunity to look at Stu's spreadsheet. I shall find the time to this week and I will see how I get on.
Stu, I get this impression that you feel that there is a lack of a definitive guide to smoke and its control. If this is so why do you thin sok? Is it the complexity of the subject, a lack of research or something else? To me there seems to be a large number of sources of information, each one slightly different. When I was studying mechanical engineering we were recommended one or maybe two course books which would tell us what we needed know. They may not have been particularly good reads but they did the job. It doesn't seem to be the case here.
-
Hi Willo,
There is plenty of guidance but as you are starting to see it isn't consistent.
Remember this, the subject is relatively new, lacks historical data and is still subject to people's evolving and differing ideas.
The tests that are required to evaluate new or improved models are very expensive and can only be undertaken at a few sites.
The models that are out there are probably a little conservative (i.e. erring on the side of safety).
There is diminishing motivation to go to the expense of developing more accurate models as the current range of models seem to be put to cost-effective use time and again and seem adequate for current building practices.
The buildings in which the current models are used for design of systems are all quite new, they are generally relatively expensive buildings and therefore relatively well managed. This means that they tend not to have fires in them anyway.
No one is quite sure if we are getting away with it for the time being whilst the systems are not up to the job or, as should be hoped (and I generally believe) , the systems are perfectly suitable to meet their objectives.
The question is, or will be, can these buildings, built to what sometimes appear to be ad hoc standards, stand the test of time.
All current models are guesses but they are the best guesses we have if we want to build the way we do. The science, and I use that term reservedly, is young and for the time being we have little choice but to put up with the vagaries of youth.
And it's not just the models that can be controversial but also the acceptance criteria - I know of at least one building where it is anticipated that, during a fire, people will have to make their way some distance through smoky conditions with visibility down to 10m - but not just a few people, as might be intuitively acceptable in a block of flats say, but thousands upon thousands of people - I can't see it working personally. All I can see is a disaster waiting to happen.
We will know in about 40 years time when the buildings are old and mis-managed and when they've had a few fires.
Ask me again then.
Stu
ps Having said all that, with judicious application of the models and care taken over all other fire safety matters, we can provide buildings that are safe.
-
As someone who used to work with the leading experimenters on smoke control systems at the Fire Research Station, I can echo Stu's comments about the problems of the expenses involved in developing or evaluating new models.
It is particularly difficult to check out a new building designed on the basis of a computer model of smoke control; even with well-designed 'hot smoke' tests they often can't be run to the limits of a system because damage might be caused - which the owners of a new building would not appreciate, of course! So one has to run a test which only reaches perhaps half the maximum capacity of a system and hope that gives a reasonable approximation to confirm the system design.
There is an inherent variability in the growth of fires; I used to reckon that if an experimental fire (using actual fuels, not controlled gas burns) was repeated and the data from the tests agreed to within 10% we were getting a repeatable fire!
-
There is an inherent variability in the growth of fires; I used to reckon that if an experimental fire (using actual fuels, not controlled gas burns) was repeated and the data from the tests agreed to within 10% we were getting a repeatable fire!
That's a point John. One of the things that I dislike about conventional fire engineering is that deterministic (i.e. pin point and precise, purportedly accurate) results are produced when, in reality, a true reflection of reality would be if the results were given as a distribution - that is to say, as a range of possible outcomes with associated probabilities.
I appreciate that the data does not exist and the variables are not always foreseeable enough to generate accurate outcome distributions. What is important is that people recognise that the deterministic results they produce are only indicative of approximately what might happen in reality. Results should not be taken, as they unfortunately often are, as precisely what will happen in reality.
Think of weather forecasts. They do their best, poor souls, but are sometimes right and sometimes wrong. And because they are sometimes wrong, the value of their correct predictions is diminished because people lose confidence in the forecasts generally. How much better they would be to give probabilities of possible weather instead of deterministic predictions. I would be much happier knowing that there was a 40% chance of a rain shower lasting between one and two hours tomorrow rather than them either telling me that it will or will not rain. I could make my own decisions then on how to tackle the potentialities of the weather and would not get annoyed when the deterministic forecast was wrong. Forecasts could be correct almost 100% of the time if they all adopted this probabilistic practice. Some do already, I know, but most of the popular ones I see do not and are wrong half the time.
Where was I...?
Never mind.
Stu
-
You two have brought up some very interesting points. Stu's post on the 19th has prompted me to ask a question which I have been asking myself recently. Are there any records of these systems operating during a real building fire?
I understand what is being said about the difficulties of producing fire engineered solutions designed around a design fire size. It isn't that suprising when comparing the variables that other engineering disciplines have to deal with. When modeling other systems for engineering purposes the variables are comparatively fewer and easier to control than those in a fire. Where even slight differences in the composition of the fuel load can make big changes in the outputs that are trying to be analysed and modeled. Maybe fire engineers should take a leaf out of the books of other engineers like structural engineers. I had a chat with one of them in the office today to get some idea of the scale of the factor of safety (the technical term is a fudge factor). It turns out it can be up to 35% over the design loads, sometimes more. Perhaps designing systems which will cope with a similar variation of design fire size would help provide a more effective solution. I suppose the next question to ask, especially for the case in point, would the clients be willing to pay for equipment with that much more capacity.
-
Generally speaking, the suggestions made for smoke control systems by my colleagues at FRS were conservative and include some margins for safety.
For example, later work by myself on sprinklered fires before I retired indicated that the reduction of the '5MW' design fire to 2.5MW for sprinklered scenarios had a considerable safety margin - most sprinklered fires rarely got above 250kW in size and were rapidly reduced to a tenth of that after sprinkler operation. (Whereas similar unsprinklered fires reached anything up to 7MW!) These and other test fires were looked at about ten years ago in the Fire Engineer's Journal, in an article by Penny Morgan I recall. (Sorry, can't find my copy!)
-
You two have brought up some very interesting points. Stu's post on the 19th has prompted me to ask a question which I have been asking myself recently. Are there any records of these systems operating during a real building fire?
I understand what is being said about the difficulties of producing fire engineered solutions designed around a design fire size. It isn't that suprising when comparing the variables that other engineering disciplines have to deal with. When modeling other systems for engineering purposes the variables are comparatively fewer and easier to control than those in a fire. Where even slight differences in the composition of the fuel load can make big changes in the outputs that are trying to be analysed and modeled. Maybe fire engineers should take a leaf out of the books of other engineers like structural engineers. ...
In addition to Stu, Civvy, Kurnal and John's Adds..., I would say;
To have real-world genuine records saved in a database style of various case studies..., the existing fire safety systems have to integrate electronics data acquisition facilities to record loads fire safety aspects during real emergencies, and then Failure Analysis have to be carried out to assess the real scenario against the initial FSE design... this assessment and comparison may improve the probabilistic concept; which is sensibly much reasonable then the deterministic solution (as stated by Stu). particularly when enhancing the Probability of success Ps this will automatically decrease the probability of failure Pf , since their summation, Ps + Pf = 1
Also you may consider the university of Ulster FireSERT institute ; http://prospectus.ulster.ac.uk/course/?id=7759