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Manufacturing Floor Ventilation

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#53251

Manufacturing Floor Ventilation | 18 January, 2008

I have searched through the topics here and none seem to address this specifically. I was wondering if anyone had any links/info directly showing how proper ventilation for fume extraction on a manufacturing floor should be handled. From my research I have found that generaly you want a negative pressure on your manufacturing floor.(pull system)This will draw fumes out and not allow them to linger in the air like they would in a positive pressure room. Also, there should be a minimum of 3 air changes/hour. Additionaly there should be local fume extractors on hand soldering stations. Reflow ovens ofcourse should have proper CFM pulling fumes from the oven. Does this sound right to you guys /gals?

Thanks, B

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#53300

Manufacturing Floor Ventilation | 22 January, 2008

no one has any input in this department?

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#53321

Manufacturing Floor Ventilation | 22 January, 2008

A minimal ventilation rate of 0.05 cfm per square foot, the recommendation of the 1998 International Mechanical Code. However, this may not take into account other potential building contaminants from such sources as propane forklifts, which require a minimum makeup air ventilation rate of 5,000 cfm per vehicle, according to the American Conference of Governmental Industrial Hygienists.

Given that you have your wave and oven vented properly and ventilation at the hand soldering stations, were are your fumes coming from?

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#53330

Manufacturing Floor Ventilation | 23 January, 2008

Actually we don't have local fume extraction at our soldering stations. We have 4 going at a time. I was researching last night and found this website. http://www.engineeringtoolbox.com/air-change-rate-room-d_867.html It indicates 10-15 air changes per hour for a Factory with Fumes. Previousely I found a website that indicated at least 3 air changes per hour was recommended. Luckily we have very high ceilings, but when something burns in the oven or we oil the chains etc.. or something falls in the solder pot etc... or we wax the floors....the factory is unbearable for at least a couple days.

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#53333

Manufacturing Floor Ventilation | 23 January, 2008

"A minimal ventilation rate of 0.05 cfm per square foot," This would be per Cubic Feet correct? In our factory that would be about 40,000CFM.(3 ACH) If we wanted 10 ACH we would need apprx. 120,000CFM. We probably have about 2,000-4,000CFM currently.(.3ACH)

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#53340

Manufacturing Floor Ventilation | 23 January, 2008

Ventilation rates express the flow rate of outside air brought into a building and are typically normalized by the volume of space being ventilated (air changes per hour), by the area of the floor being ventilated (cubic feet per min (cfm) per ft2) or by the number of people being served (cfm per person).

Your "15 cfm" is per person. Watch your units.

Standards are: * 1997 Uniform Mechanical and Building Codes * 1993 BOCA National Mechanical Code * 1998 International Mechanical Code * ANSI/ASHRAE 62-1989

See if you can find them in our public library. We can.

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#53618

Manufacturing Floor Ventilation | 12 February, 2008

Like most things - "it depends". There just isn't a simple formula for applying general air exchange rates. Your baseline should be doing some air quality (industrial hygiene) testing to see what types of exposures the workers have. THEN, you can look into appropriate types of local exhaust ventilation. One of the best references is "Industrial Ventilation" A Manual of Recommended Practice", published by the American Conference of Governmental Industrial Hygienists. Beware, though - this isn't a 'do it yourself' item, any more than you'd order a book on surgery and take out your own appendix.

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#53619

Manufacturing Floor Ventilation | 12 February, 2008

You have 4 waves without ventilation? Do you work for Hell Inc?

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