Ventilation/extraction for spray booth...?

  1. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
    Currently building a spray booth/workshop using negative air pressure. I'm at the point now where I need to think about installing the inlet vents and extraction.

    Firstly, where to place the air induction vents. Below is a picture of the front structure... October 2019.JPG

    From what I've read, I ought to place the induction vents on the front wall above head height (6-7 foot from the floor?

    Secondly and this is due to inexperience, what sort of induction vents do I require? I believe I will be needing a form filtration is needed to reduce dust entering the building, if so how is this achieved?

    Thirdly I'm lead to believe the extraction fans ought to be placed on the back wall, should these be placed at the same height as the induction vents or at a lower height?

    All info appreciated :)
     
  2. slim_boy_fat

    slim_boy_fat Forum Supporter

    Can't help with the vent type, but I'd think they should be placed offset to one another - one high, the other low so as to create a 'swirl' in the airflow?
     
  3. gaz_moose Member

    Messages:
    937
    Location:
    tamworth staffordshire
    id put the intake low down on one side and the extraction up high on the other side. and then as slim boy says one on the bottom left and the other on the top right.

    you can buy ' paint booth intake filters ' that are a bit like a car's air filter or buy it on a big roll and cut to size (its probably the same stuff they use in electrical cabinets). personally I would just make a frame that I could stretch old cotton T-shirts over. but then it depends on what you are after.

    also watch out for the extraction fan type as a regular fan could ignite the vapours or something along those lines.
     
  4. Parm

    Parm I have fun doing stuff

    Messages:
    9,294
    Location:
    Towcester
    This should give you an idea, it comes from the industrial process ventilation bible
    B6363078-2B23-4C88-8EFD-41620448195C.jpeg
     
    rtcosic and slim_boy_fat like this.
  5. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
    Thanks for the reply :) So in theory, let's say there is two vents in the front wall. Are you saying that one should be placed slightly higher than the other, say a foot or so?
     
  6. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
    Do you not think that by placing inlet vents low down that there's a greater risk of dust/debris entering the area as opposed to a higher position? I like the idea of ATEX rated equipment but alas the wallet doesn't. Yeah, I know it's my funeral or should we say cremation ;)
     
  7. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
    Thanks for the photo there :) Have you employed that design yourself in you build?
     
  8. carbon

    carbon Member

    Messages:
    1,180
    Location:
    S. Glos. U.K
  9. Slowcoach Member

    Messages:
    190
    Location:
    Bedford
    Will placing inlet high not drag any particles across horizontal surfaces, I’d keep in and out low. You only need to extract the overspray and once that’s done bake the paint.
    I think you’ll only get positive pressure if you force more air in than extract and I presume this is only required when the doors open into a workshop.
     
  10. Parm

    Parm I have fun doing stuff

    Messages:
    9,294
    Location:
    Towcester
    I check performance of operation when required. This is the benchmark standard
     
    slim_boy_fat likes this.
  11. slim_boy_fat

    slim_boy_fat Forum Supporter

    Don't see why, but I'd be guided by Parm's plan above.
     
  12. hazzabo Member

    Messages:
    18
    Location:
    Wokingham, United Kingdom
    Regarding lighting: I saw a home built booth once that used ordinary flourescent lights behind wired glass panels set into the roof void and sealed with foam tape. The same booth also had a loose sheet of plasterboard over a roof opening as a “blow out” panel in case the worst happened. No idea how effective that would be in reality.
     
  13. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
    That’s great info there :) thanks for the links I’ll endeavour to order some. Do you know What sort of filter housings accept these filters?
     
  14. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
    I think the safety glass is a good idea. I might employ such an idea myself :)
     
  15. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
    I’m gonna allow the paint to cure at natural ambient temperature rather than bake it. I’m not painting for commercial reasons.

    Placing the inlet vents in a high position as opposed to a low one is worth the trade off I feel. Particles could be dragged across the work being attended to but I suspect less will enter the area than if the vents were mounted lower.
     
  16. carbon

    carbon Member

    Messages:
    1,180
    Location:
    S. Glos. U.K
  17. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
  18. carbon

    carbon Member

    Messages:
    1,180
    Location:
    S. Glos. U.K
    I could take some Monday if it helps
     
  19. the snooper

    the snooper getting older by the day

    Messages:
    20,066
    Location:
    Hull UK
    The booths I've used have the inlet filters on the ceilings and extraction low down at the back of the booth this is so the air moves the mist downwards and out however unless you have a fan capable of moving masses of air you will be disappointed there is a formula online to calculate the CFM required for a given room size and it can be in the thousands
     
    slim_boy_fat and carbon like this.
  20. The Z'eer

    The Z'eer Member

    Messages:
    851
    Location:
    Essex
    If you could, I’m sure it’ll make all the difference. Thanks :)
     
Advertisements