LEV External vent height. Options  Watch this topic  Print this topic » Normal Threaded

Previous Topic Next Topic

Admin		#1 Posted : 07 October 2006 17:19:00(UTC)
Rank: Guest		Posted By Saracen11 Hello folks, does anyone know where I can find the standards that indicate the required height of an external vent from an LEV? The vent will be at the end of a system venting from a non two-pack spray booth. In this case, the premises are located on the 1st floor of a multi floor building... the approximate height of the 1st floor to where the vent comes out is 15M, is it already at a sufficient height? Regards
User Profile View All Posts by User View Thanks

Admin		#2 Posted : 07 October 2006 17:51:00(UTC)
Rank: Guest		Posted By Smurfer Convention says 3m above roof/ridge height - partly to allow for dispersion of the emission without it becoming entrained within the building eddy/wake and partly to stop anyone sticking their head down the stack. There are no legal requirements unless it is specified in a LAPPC or IPPC Permit. Andy
User Profile View All Posts by User View Thanks

Admin		#3 Posted : 07 October 2006 17:57:00(UTC)
Rank: Guest		Posted By Paul Leadbetter There is not a simple answer to this but the discharge point should be some distance above the roof of the building! How many floors are above your proposed discharge point? Paul
User Profile View All Posts by User View Thanks

Admin		#4 Posted : 07 October 2006 17:59:00(UTC)
Rank: Guest		Posted By Paul Leadbetter Sorry, didn't answer the question; see chapter 5 of the Industrial Ventilation manual published by ACGIH. Paul
User Profile View All Posts by User View Thanks

Admin		#5 Posted : 07 October 2006 18:28:00(UTC)
Rank: Guest		Posted By Saracen11 Hi, the problem with ensuring the end of the duct being above the top of the building is that it is 6 floors high! If the outlet was far enough away from say, a window of a neighbour and suitably located to ensure fixing and maintenance, is this enough? Paul, I'll have a look at the document you suggested. Thanks - any more comments are welcome. Regards
User Profile View All Posts by User View Thanks

Admin		#6 Posted : 07 October 2006 21:15:00(UTC)
Rank: Guest		Posted By Paul Leadbetter How much paint are we talking about? Paul
User Profile View All Posts by User View Thanks

Admin		#7 Posted : 07 October 2006 22:16:00(UTC)
Rank: Guest		Posted By Barry Cooper The height depends on other buildings within a specified radius from the vent.The minimum height is 3 metres, but this will increase due to proximity of other buildings. I used to be clued up but it is several years now since I dealt with it. Guidance (PG series) is available from the Environment Agency. Try their web site. Barry
User Profile View All Posts by User View Thanks

Admin		#8 Posted : 09 October 2006 21:00:00(UTC)
Rank: Guest		Posted By Saracen11 Hello. Thank you to all that responded. I don't know how much paint is to be used on a daily basis. I am gonna have a look at the recommended document this week - hopefully. Thanks again. Regards
User Profile View All Posts by User View Thanks

Admin		#9 Posted : 10 October 2006 09:46:00(UTC)
Rank: Guest		Posted By Ali You may be looking in the wrong place. Think about the Environmental Protection Act 1990 and the risk of causing "statutory nuisance". Also, if it is an "authorised process" it will almost certainly be required to dicharge at a certain height.
User Profile View All Posts by User View Thanks

GeoffB4		#10 Posted : 24 April 2010 11:58:36(UTC)
Rank: Forum user		Only thread I could find on this topic. I've not been able to obtain the environment agency guidance 'Guidelines on Discharge Stack Heights for Polluting Emissions' - any ideas. Saracen11 - were you able to get hold of anything? I remember going into stack height in depth during Diploma training in the early 90s but those notes (and memories of the subject) are long gone. I'm surprised trawling the internet that I haven't been able to find any information.
User Profile View All Posts by User View Thanks

Adrian Watson		#11 Posted : 24 April 2010 16:37:53(UTC)
Rank: Forum user		As a general rule the minimum chimney heights should be 5 m above the roof ridge level or adjacent buildings and the discharge velocity should be at least 15 m/s. Cowls should not be fitted to the discharge vent. A rough guide to vent height is: H = sqrt(9M/20C) Where: H = stack height (metres) M = mass rate of emission (kg/day) C = 1/40 OEL (mg/m^3) or maximum permitted 3-minute mean ground level concentration. Regards Dust and Fume Control 2nd Edn IChemE 1992 p 133
User Profile View All Posts by User View Thanks

GeoffB4		#12 Posted : 25 April 2010 19:56:01(UTC)
Rank: Forum user		Many thanks AKW
User Profile View All Posts by User View Thanks

GeoffB4		#13 Posted : 02 May 2010 09:46:18(UTC)
Rank: Forum user		Took me a while AKW but managed to get a copy of the book you mentioned (ex OU library). Gives me all the answers. Thanks for the reference.
User Profile View All Posts by User View Thanks

Users browsing this topic

Guest