arcticpenguin
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http://www.newscientist.com/news/news.jsp?id=ns99994427
No mention of whether they consulted a Feng Shui expert.
UV for 'sick building syndrome'
- Thread starter arcticpenguin
- Start date
geni
Anti-homeopathy illuminati member
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My local sea life centre uses excatly this method to kill bacteria in the water when they bring in sea water.
How long do you think it will be before the woowoo start going on about about UV radtion in air conditioning creating the wrong type of ions?
How long do you think it will be before the woowoo start going on about about UV radtion in air conditioning creating the wrong type of ions?
SteveGrenard
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Actually UV light and oxygen (in the air) creates Ozone (O3) and this is definitely not a good thing to breathe either as ozone is highly irritating and causes many of the symptoms these folks are suffering from as a result of bacteria and fungi.
My hope would be that they use the UV to treat the system when the building is empty but to shut it off when inhabited. I dont think I would want to spend 8+ hours a day in a tight building breathing ozone anymore than I like the idea of inhaling fungal spores or airborne bacteria.
My hope would be that they use the UV to treat the system when the building is empty but to shut it off when inhabited. I dont think I would want to spend 8+ hours a day in a tight building breathing ozone anymore than I like the idea of inhaling fungal spores or airborne bacteria.
Rolfe
Adult human female
Am I the only one thinking "deep suntan and skin cancer" here? Or have I got the wrong end of the stick?
Rolfe.
Rolfe.
The systems are actually intellegently designed. The UV is in the entrance to the air handlers, so what it does is kill most of the spores, so the fungus load/etc on the building ramps downwards for quite some time after the UV lamps are installed, i.e. it gets beter and better over time as the load (bacteria and fungus) die out.
The Ozone load should be nonexistant unless they misinstalled it.
Ozone is BAD for you, indeed.
The Ozone load should be nonexistant unless they misinstalled it.
Ozone is BAD for you, indeed.
Rolfe
Adult human female
OK, I'm a bit slow tonight.geni said:
Rolfe.
arcticpenguin
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Ozone is bad for you, but it has a very short half-life. It is used in many places for water purification, and doesn't leave lingering by-products like chlorine does.
SteveGrenard
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Here are two abstracts on the subject from Medline. The first one is the original article on which the New Scientist article is based. The second is an earlier study by German researchers with some interesting results.
Effect of ultraviolet germicidal lights installed in office ventilation systems on workers' health and wellbeing: double-blind multiple crossover trial
Dick Menzies, Julia Popa, James A Hanley, Thomas Rand, Donald K Milton
--------------------------------------------------------------------------------
Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute (D Menzies MD, J Popa MEng) and Department of Epidemiology and Biostatistics, McGill University, Montreal, Canada (D Menzies MD, J A Hanley PhD); Department of Biology, St Mary's University, Halifax, Nova Scotia, Canada (T Rand PhD); and Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA (D Milton PhD)
--------------------------------------------------------------------------------
Correspondence to: Dr Dick Menzies, Respiratory Epidemiology Unit, Montreal Chest Institute, McGill University, 1110 Pine Avenue West, Room 103, Montreal, Quebec, Canada H3A 1A3 (e-mail:dick.menzies@mcgill.ca)
Summary
Background Workers in modern office buildings frequently have unexplained work-related symptoms or combinations of symptoms. We assessed whether ultraviolet germicidal irradiation (UVGI) of drip pans and cooling coils within ventilation systems of office buildings would reduce microbial contamination, and thus occupants' work-related symptoms.
Methods We undertook a double blind, multiple crossover trial of 771 participants. In office buildings in Montreal, Canada, UVGI was alternately off for 12 weeks, then turned on for 4 weeks. We did this three times with UVGI on and three times with it off, for 48 consecutive weeks. Primary outcomes of self-reported work-related symptoms, and secondary outcomes of endotoxin and viable microbial concentrations in air and on surfaces, and other environmental covariates were measured six times.
Findings Operation of UVGI resulted in 99% (95% CI 67-100) reduction of microbial and endotoxin concentrations on irradiated surfaces within the ventilation systems. 771 participants appeared to remain masked, and reported no adverse effects. On the basis of within-person estimates, use of UVGI was associated with significantly fewer work-related symptoms overall (adjusted odds ratio 0·8 [95% CI 0·7-0·99]), as well as respiratory (0·6 [0·4-0·9]) and mucosal (0·7 [0·6-0·9]) symptoms than was non-use. Reduction of work-related mucosal symptoms was greatest among atopic workers (0·6 [0·5-0·8]), and never-smokers (0·7 [0·5-0·9]). With UVGI on, never-smokers also had large reduction of work-related respiratory (0·4 [0·2-0·9]), and musculoskeletal symptoms (0·5 [0·3-0·9]).
Interpretation: Installation of UGVI in most North American offices could resolve work-related symptoms in about 4 million employees, caused by microbial contamination of heating, ventilation, and air-conditioning systems. The cost of UVGI installation could in the long run prove cost-effective compared with the yearly losses from absence because of building-related illness.
Lancet 2003; 362: 1785-91
Zentralbl Hyg Umweltmed. 1997 Aug;200(2-3):137-51.
[Sick building syndrome and HVAC system: MVOC from air filters]
[Article in German]
Schleibinger HW, Wurm D, Moritz M, Bock R, Ruden H.
Institut fur Hygiene der FU Berlin.
Growth and emissions of volatile metabolites of microorganisms on air filters are suspected to contribute to health complaints in ventilated rooms. To prove the microbiological production of volatile organic compounds (MVOC), concentrations of aldehydes and ketones were determined in two large HVAC systems. The in situ derivated aldehydes and ketones (as 2,4-dinitrophenyl-hydrazones) were analysed by HPLC and UV detection. The detection limit of each compound was 1 ppb (margin of error < 10%). Field measurements were carried out before and after the prefilters and the main filters, respectively, to investigate whether aldehydes and ketones increase in concentration after filters of HVAC systems. First results show that the compounds formaldehyde, acetaldehyde and acetone could be detected before and after the filters. The concentrations of these VOC after the filters were significantly increased--as a mean over twenty measurements--, especially as far as filters made of glass fibre are concerned. However the found concentrations were low and mostly comparable to outdoor findings. In simultaneous laboratory experiments pieces of used filter material of one HVAC system and unused filter pieces (for blank values) were examined in small incubation chambers to investigate the possible production of MVOC. For the incubation a temperature of 20 degrees C and a relative humidity of 95% was chosen. In these experiments an almost identical spectrum of compounds (formaldehyde and acetone) was found as in the field measurements. The concentrations of these compounds were higher in the chambers with the used filter pieces. The concentration of acetone ranged up to almost 12 mg/m3.--As our field experiments correspond with our laboratory experiments, we assume that the microbial production of volatile organic compounds in HVAC systems under operating conditions is possible.
Effect of ultraviolet germicidal lights installed in office ventilation systems on workers' health and wellbeing: double-blind multiple crossover trial
Dick Menzies, Julia Popa, James A Hanley, Thomas Rand, Donald K Milton
--------------------------------------------------------------------------------
Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute (D Menzies MD, J Popa MEng) and Department of Epidemiology and Biostatistics, McGill University, Montreal, Canada (D Menzies MD, J A Hanley PhD); Department of Biology, St Mary's University, Halifax, Nova Scotia, Canada (T Rand PhD); and Department of Environmental Health, Harvard School of Public Health, Boston, MA, USA (D Milton PhD)
--------------------------------------------------------------------------------
Correspondence to: Dr Dick Menzies, Respiratory Epidemiology Unit, Montreal Chest Institute, McGill University, 1110 Pine Avenue West, Room 103, Montreal, Quebec, Canada H3A 1A3 (e-mail:dick.menzies@mcgill.ca)
Summary
Background Workers in modern office buildings frequently have unexplained work-related symptoms or combinations of symptoms. We assessed whether ultraviolet germicidal irradiation (UVGI) of drip pans and cooling coils within ventilation systems of office buildings would reduce microbial contamination, and thus occupants' work-related symptoms.
Methods We undertook a double blind, multiple crossover trial of 771 participants. In office buildings in Montreal, Canada, UVGI was alternately off for 12 weeks, then turned on for 4 weeks. We did this three times with UVGI on and three times with it off, for 48 consecutive weeks. Primary outcomes of self-reported work-related symptoms, and secondary outcomes of endotoxin and viable microbial concentrations in air and on surfaces, and other environmental covariates were measured six times.
Findings Operation of UVGI resulted in 99% (95% CI 67-100) reduction of microbial and endotoxin concentrations on irradiated surfaces within the ventilation systems. 771 participants appeared to remain masked, and reported no adverse effects. On the basis of within-person estimates, use of UVGI was associated with significantly fewer work-related symptoms overall (adjusted odds ratio 0·8 [95% CI 0·7-0·99]), as well as respiratory (0·6 [0·4-0·9]) and mucosal (0·7 [0·6-0·9]) symptoms than was non-use. Reduction of work-related mucosal symptoms was greatest among atopic workers (0·6 [0·5-0·8]), and never-smokers (0·7 [0·5-0·9]). With UVGI on, never-smokers also had large reduction of work-related respiratory (0·4 [0·2-0·9]), and musculoskeletal symptoms (0·5 [0·3-0·9]).
Interpretation: Installation of UGVI in most North American offices could resolve work-related symptoms in about 4 million employees, caused by microbial contamination of heating, ventilation, and air-conditioning systems. The cost of UVGI installation could in the long run prove cost-effective compared with the yearly losses from absence because of building-related illness.
Lancet 2003; 362: 1785-91
Zentralbl Hyg Umweltmed. 1997 Aug;200(2-3):137-51.
[Sick building syndrome and HVAC system: MVOC from air filters]
[Article in German]
Schleibinger HW, Wurm D, Moritz M, Bock R, Ruden H.
Institut fur Hygiene der FU Berlin.
Growth and emissions of volatile metabolites of microorganisms on air filters are suspected to contribute to health complaints in ventilated rooms. To prove the microbiological production of volatile organic compounds (MVOC), concentrations of aldehydes and ketones were determined in two large HVAC systems. The in situ derivated aldehydes and ketones (as 2,4-dinitrophenyl-hydrazones) were analysed by HPLC and UV detection. The detection limit of each compound was 1 ppb (margin of error < 10%). Field measurements were carried out before and after the prefilters and the main filters, respectively, to investigate whether aldehydes and ketones increase in concentration after filters of HVAC systems. First results show that the compounds formaldehyde, acetaldehyde and acetone could be detected before and after the filters. The concentrations of these VOC after the filters were significantly increased--as a mean over twenty measurements--, especially as far as filters made of glass fibre are concerned. However the found concentrations were low and mostly comparable to outdoor findings. In simultaneous laboratory experiments pieces of used filter material of one HVAC system and unused filter pieces (for blank values) were examined in small incubation chambers to investigate the possible production of MVOC. For the incubation a temperature of 20 degrees C and a relative humidity of 95% was chosen. In these experiments an almost identical spectrum of compounds (formaldehyde and acetone) was found as in the field measurements. The concentrations of these compounds were higher in the chambers with the used filter pieces. The concentration of acetone ranged up to almost 12 mg/m3.--As our field experiments correspond with our laboratory experiments, we assume that the microbial production of volatile organic compounds in HVAC systems under operating conditions is possible.
I was going to ask about stuff like VOCs--but I was thinking about building-material sources, degassing from carpeting, upholstry, and that secretary who douses herself with enough perfume to drown a horse. But I guess it pays not to jump to conclusions about a source until after doing a bit of investigating.