QUOTE(khf20 @ Sep 19 2011, 03:25 PM)
Hi,
you can find ozone generators from swimming pool suppliers. Ozone is also used to clean swimming pools.
I know UM Physics Lab had a product a few years ago using Plasma physics to generate Ozone. You might consider giving them a call.
Added on September 19, 2011, 3:39 pmHi,
I notice this explanation below on "TRUE" HEPA efficiency and I found it rather misleading.
I guess it is literally right, that the TRUE HEPA can only get more efficient; actually it might become 100% efficient and stop becoming a filter.
Another interpretation of efficiency is to couple the filtering capacity with the pressure needed to get air to flow through the filter.
It is more reasonable and natural interpretation as we commonly understand the word efficiency.
If the HEPA gets clogged up, more and more air pressure would be needed to push air through the filter (as the HEPA filter becoming more efficient!). Therefore the fan motor would have to work harder or if the motor is working at a constant rate, the air-flow would be slower. In any case, the AP would be working at reduced efficiency instead of increased efficiency as the explanation below suggests to the casual reader.
Also, I would suspect that "ALL" such filters tend to be "more efficient" as time goes by......
It's all about efficiency and staying ahead of the particle count in your home or office. TRUE HEPA Air Purifiers offer a 98% and above efficiency when using a certified 99.97% (HEPA FILTER). The problem with regular HEPA is on the avg. they only operate around a 37% efficiency where every 100 fine particles captured will release 63 back into the space. As for Ionizers, they only clean the air temporarily and work to an avg. of 2% efficiency. Ozonators are 0% efficient at filtering fine particles.
Fine Particles are typically noted as 5 microns in size, ultra fine 0.5 microns. TRUE HEPA efficiency is measured down to 0.3 microns which are the key particles such as dust mites, dust mites debris and most airborne bacteria which is why most of the children who are now age 5-6 suffer from Allergic Rhinitis in Malaysia.
Most homes in Malaysia on a regular day (not during Haze, and not after a heavy rain) show fine particle counts greater than 600,000 per liter of air. Indoor Air Quality (IAQ) is typically 350,000-450,000 where the WHO states clearly usafe levels at 105,000 or greater.
The ideal reading for an environment is under this 105,000 level but still is noted as having long term negative effects.
We are the only company offering IAQ audits in SE Asia using the top digital particle counters in the world to show REAL before and after results. Typically we have found bedrooms exhibiting 400K+ particle counts to be reduced to under 10K with our AP's within a few short hours.
Efficiencies of particle capture are absolutely key in our part of the world. If you only operate at a 37% efficiency then capturing 400,000 particles and releasing 250,000 back into your space really has limited benefit. How do you know if your AP is working? You should feel the difference! You should be finding your Allergic Rhinitis symptoms slowly go away! You should at some point relieve yourself from having to pay for allergy medicines and steroid sprays.
As for the comment above on clogged HEPA, this is the problem with normal HEPA Air Purifiers and not changing your filter regularly. Either the efficiencies drop off of the charts or the motor simply burns out! For our AP's, we sample the efficiencies during operation and if we cannot meet our 98% above TRUE HEPA levels, the filter change light will illuminate.
For Malaysia, the average filter life of our 2 main models PARALDA and A375UV if operated 8 hours a day see 14-18 months before a change is needed. If 12 hours per day 10-14 months and if 24/7, we see 6-8 months! Again it all depends on the source of outside air and any contamination of indoor air.
Before purchasing an AP, do your homework, get educated and read reviews by real users. Demand the company show you whether they can prove the HEPA filter they provide is certified first of all, then ask for their efficiency numbers on each specific model for filtering fine particles down to 0.3 microns and how long they can hold this level. Clean Air Delivery Rates (known as CADR) are only based on a 72 hour test so these numbers are insignificant for claims. Do you change your filter every 72 hours? 72 days? 72 weeks - Maybe!
Better yet, challenge them to come to your home or office and do a demo armed with a certified Digital Fine Particle Counter, test your air before hand and after in real time and show you the results. Seeing is believing, only a few can deliver, and the rare one's improve your health.
Added on September 30, 2011, 8:34 amHello All, this is a new report from WHO which is clear about the the death toll related to both indoor and outdoor air pollution. The key component you should be focussed on here is fine particles.
We cannot emphasize enough the importance of choosing an air purifier which can capture fine particles less than PM 10 OR Particles less than 10 micrometers (microns) in width or less.
Again, it goes straight to the matter of using an air purifier who's efficiency rate is high enough to capture these particles first but not re-introduce them into your indoor enviroment.
TRUE HEPA is just that, a HEPA filter (99.97%) which operates at an efficiency of 98% or above so that a maximum of only 2 particles out of 100 re-enter.
The average HEPA filter Air Purifier only works at an efficiency of around 37% (costs RM1200-2000). Some leading brands of HEPA in Asia may work upto 60-75% but you have to pay RM2500+.
Take this one step further and start looking at ULTRA FINE Particles down to 0.5 microns such as small bacterial sources and Dust Mites (5.0 microns) right down to Dust Mite Debris and very small bacterail (0.5 microns) and you really need to make a Smart Decision.
The ALEN Paralda has been proven to work so well because of its TRUE HEPA Efficiency tested at 99.42% right down to 0.3 microns and with your LOWYAT Discount is only priced at RM2450. This is simply why we are #1!
Tackling the global clean air challenge
News release
26 September 2011 | Geneva - In many cities air pollution is reaching levels that threaten people's health according to an unprecedented compilation of air quality data released today by WHO. The information includes data from nearly 1100 cities across 91 countries, including capital cities and cities with more than 100 000 residents.
Over 2 million people die from indoor and outdoor air pollution
WHO estimates more than 2 million people die every year from breathing in tiny particles present in indoor and outdoor air pollution. PM10 particles, which are particles of 10 micrometers or less, which can penetrate into the lungs and may enter the bloodstream, can cause heart disease, lung cancer, asthma, and acute lower respiratory infections. The WHO air quality guidelines for PM10 is 20 micrograms per cubic metre (µg/m3) as an annual average, but the data released today shows that average PM10 in some cities has reached up to 300 µg/m3.
Main findings
The main findings contained in the new compilation are:
Persistently elevated levels of fine particle pollution are common across many urban areas. Fine particle pollution often originates from combustion sources such as power plants and motor vehicles.
The great majority of urban populations have an average annual exposure to PM10 particles in excess of the WHO Air Quality guideline recommended maximum level of 20 µg/m3. On average, only a few cities currently meet the WHO guideline values.
For 2008, the estimated mortality attributable to outdoor air pollution in cities amounts to 1.34 million premature deaths. If the WHO guidelines had been universally met, an estimated 1.09 million deaths could have been prevented in 2008. The number of deaths attributable to air pollution in cities has increased from the previous estimation of 1.15 million deaths in 2004. The increase in the mortality estimated to be attributable to urban air pollution is linked to recent increases in air pollution concentrations and in urban population size, as well as improved data availability and methods employed.
"Air pollution is a major environmental health issue and it is vital that we increase efforts to reduce the health burden it creates," said Dr Maria Neira, WHO Director for Public Health and Environment. "If we monitor and manage the environment properly we can significantly reduce the number of people suffering from respiratory and heart disease, and lung cancer. Across the world, city air is often thick with exhaust fumes, factory smoke or soot from coal burning power plants. In many countries there are no air quality regulations and, where they do exist, national standards and their enforcement vary markedly. "
Greater awareness of health risks
WHO is calling for greater awareness of health risks caused by urban air pollution, implementation of effective policies and close monitoring of the situation in cities. A reduction from an average of 70 µg/m3 of PM10 to an annual average of 20 µg/m3 of PM10 is expected to yield a 15% reduction in mortality - considered a major public health gain. At higher levels of pollution, similar reductions would have less impact on reducing mortality, but will nevertheless still bring important health benefits.
"Solutions to outdoor air pollution problems in a city will differ depending on the relative contribution of pollution sources, its stage of development, as well as its local geography," said Dr Carlos Dora, WHO Coordinator for Interventions for Health Environments in the Department of Public Health and Environment. "The most powerful way that the information from the WHO database can be used is for a city to monitor its own trends in air pollution over time, so as to identify, improve and scale-up effective interventions."
Largest contributors to urban outdoor air pollution
In both developed and developing countries, the largest contributors to urban outdoor air pollution include motor transport, small-scale manufacturers and other industries, burning of biomass and coal for cooking and heating, as well as coal-fired power plants. Residential wood and coal burning for space heating is an important contributor to air pollution, especially in rural areas during colder months.
“Local actions, national policies and international agreements are all needed to curb pollution and reduce its widespread health effects" said Dr Michal Krzyzanowski, Head of the WHO European Centre for Environment and Health in Bonn, Germany. "Data from air quality monitoring that is released today, identify regions where action is most needed and allows us to assess the effectiveness of implemented policies and actions.”
Notes to editors:
Air quality data have been compiled from publicly available national or city-specific sources, which are based on results of air quality monitoring conducted by individual cities. The measurements used in the database are taken from monitoring sites in cities, including roadside, but excluding industrial and other recognized 'hot spots' that are not representative of the exposure of many people (e.g. crossings at highways) in order to avoid overestimates.
Measurements as applied in the database, including reported PM10 levels, represent annual averages. PM10 is an important indicator of urban air pollution, and the health risks associated with the complex mixtures of pollutants typically found in cities. The smaller PM10 particles are able to penetrate deep into the lungs, and also to cross into the blood, causing damage in many organ systems. In some cities, measurements of even smaller particles such PM2.5 are available, and these are also included in the database.
The data are based on measurements from 2003 to 2010, with the great majority being reported for the period 2008-2009. Data are presented for individual cities, urban populations of countries (as available), and for WHO regions.
These air quality data sets, along with the latest updates of the related burden of disease, and corresponding frequently asked questions, are available online.
For more information, please contact:
Ms Nada Osseiran
Communications Officer
WHO
Telephone: +41 22 791 4475
Mobile: +41 79 445 1624
E-mail: osseirann@who.int
Gregory Hartl
Communications Advisor
WHO
This post has been edited by Onemorething: Sep 30 2011, 08:34 AM