SV: Definition of IAQ - [was: A Comment on ASHRAE Standard 62—Ventilation for Acceptable Indoor Air Quality]

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Jim: Sorry, was not thinking about just moving the air…. I was thinking more about the costs of air-exhange rates in schoolsoffice buildings and so on…. There are people who I belive think that if you tripple orquadropple .. or more, the air-exhange rates in the buildings ventilationsystemyou will get rid off all complaints …    The " cost " of that can be high (building cost, cost ofheating, cooling, conditioning, bigger ventilation shafts, sound  etc). This is not my field, but I guess this holds true even if youuse effective fans is it not ?    There is a threshold level somewhere regarding air-exhanges … Better then to focus on the materials you put into the buildingand maintaining it properly to avoid complaints. Best regards Ole Carlson,Norway Fra:iequality [mailto:iequality ] På vegne avJim H. White SSCSendt: 1. januar 2002 09:39Til: iequality Emne: Re: Definition of IAQ - [was: A Comment on ASHRAEStandard 62—Ventilation for Acceptable Indoor Air Quality]  Ole Itis only true that moving air is expensive if we use very inefficientfan/motor/duct systems to do the work. It is not uncommon to see motor-fan setefficiencies of less than 5% in buildings (bathroom fan technologies can beless than 0.3% efficient). That means we are buying more than 20 times theenergy that we are getting supplied to the moving air stream. For the bathroomfan technology used to ventilate a house we pay for 333 times the energy orpower that is used to move the air. Conditioningair is more expensive, but the amount that people almost never costs $1 perday. Maybe that is way too much, but if you are sick in a building and betteraway, one might dispute " too expensive " with some strongly emotionswords. InSI the flow rate [L/s] times the pressure drop [Pa] / 1000 gives the flowpower in Watts. For good systems that is not a lot of energy or power. Forexample, 5 L/s against 25 Pa is only 0.125 W and over a day that is only 10.8kJ (0.003 kWh). Low efficiency systems make that bigger, but even then we aresometimes talking pennies per day. JimH. White System Science Consulting SV: Definition of IAQ - [was: A Comment on ASHRAE Standard 62—Ventilation forAcceptable Indoor Air Quality] Here in Norway , the building codestates that you should have at minimum 0,5 air exchange per hour.That means that ALL the air in the roomis changed in 2 hours….. Sounds quite rapid does it not … Is that rapid enough ?And I definetly follow the argument ofgeometry…. I am quite sure that the air below my desk in the corner is NOTchanged every two hour… (got smelly feet to prove it :-) But then again I seldom stay under thedesk for long periods of time …. Well I know it is an impossible question to answer …. that depends on so many factors … number ofpersons, sensitivities, type of environment, type of material etc., etc. … I think also that it is important toremember that most building codes states the MINIMUM requirments…. It is notillegal do do better than the minimum requirments ….But at what cost ?Moving air is quite energy consuming isit not ? Just my thoughts on this subject … Ole Carlson , Mycoteam as , Norway Fra:iequality [mailto:iequality ] På vegne avsagefarm@...Sendt: 15. september 2010 00:20Til: iequality Emne: Re: Definition of IAQ - [was: A Comment on ASHRAEStandard 62—Ventilation for Acceptable Indoor Air Quality] Carl:I would suggest a performance based definition of good IAQ,an environment that actively promotes a healthy and productive working space.To achieve this would require the rapid dilution and removal of any aircontaminants generated by the people in the occupied space, as well as the absence of anyair contaminantscapable of causing any health related complaints or symptoms.The effectiveness of the dilution and removal is a function not only of theamount of ventilation provided,but also on the geometry of how this air moves through the space. W. Bearg, PE, CIHLife Energy Associateswww.LifeEnergyAssoc.com20 Darton StreetConcord, MA 01742 Definition of IAQ - [was: A Comment on ASHRAE Standard62—Ventilation for Acceptable Indoor Air Quality] Interesting discussion about indoor airquality. Does anybody have a definition - other than the 80% rule of thumb? Ionce asked that question to a group and was accused of asking a trick question. For example, I'm looking at a report wheremeasurements were made of temperature, RH, CO and CO2. The conclusion was thatthe indoor air quality was acceptable. I have another report where measurementswere made of airborne mold by culturing and microscopy. The conclusion was theindoor air quality was acceptable. Whether or not the " acceptable " conclusion was justified, my questions are the following: What is indoor air quality? What are the data necessary tosufficiently describe indoor air quality? What are the criteria for acceptable IAQ? What are the criteria for not acceptableIAQ? Carl GrimesHealthy Habitats LLC ----- Hello , I agree. Plus how manyoccupants would actually have the data to know what the IAQ quality was intheir building?. In many cases, quality is very poor before many peoplestart to complain. Plus, who is really going to keep track and say – Ihave data that 85% of the occupants are OK with the air quality? Brad Harr From: iequality [mailto:iequality ]On Behalf Of sagefarm@...Sent: Sunday, September 12, 2010 12:01 PMTo: iequality Subject: A Comment on ASHRAE Standard 62—Ventilation forAcceptable Indoor Air Quality Dear Colleagues:Just a comment on ASHRAE Standard 62 - Ventilation for Acceptable Indoor AirQualityfor those who have not yet had the opportunity to read this Standard and whatis meant byACCEPTABLE Indoor Air Quality. For the purposes of this Standard it meansproviding a ventilation rate where it is expected that a substantial majority of thoseexposed (at least 80%)are NOT DISSATISFIED. By my reckoning this ACCEPTABILITY does NOTcorrespond to theachievement of good IAQ, despite what too many people seem to believe it means.Any comments or questions?Sincerely, W. Bearg, PE, CIH Life Energy Associateswww.LifeEnergyAssoc.com20 Darton StreetConcord, MA 01742