2.What other reasons, the influence of indoor air quality?
First of all to get to the first question:
When it comes to indoor air, we must first understand the air quality standards inside what are focused on atmospheric composition: sulfur dioxide, nitrogen dioxide, carbon monoxide and ozone, PM10 and PM2.5, TSP, NOX, lead, benzopyrene and radon gas.
The impact of outdoor air particles on indoor concentrations was considered. Equilibrium mass balance models indicate that this is a function of the penetration P through the building envelope, the air exchange rate a, and the particle decay rate k. EPA’s PTEAM Study provided an estimate for k of 0.39 h(-1) for fine particles and 1.01 h(-1) for coarse particles. Two studies suggest that P = 1 for PM(10). Using these results, the fraction of outdoor air PM(2.5) and PM(10) particles found indoors at a given air exchange rate can be calculated. The protective effect of reducing air exchange rates during periods of high outdoor particle pollution can thus be quantified.
So Indoor outdoor influence degree to see whether the two size, one is the air flow rate, the other one is particle clearance.The removal of the indoor basically can be measured by observing, can also be enhanced through many physical means, PM2.5 slower, PM10 faster (gravity settling quickly), then control the air flow rate will further strengthen building block rate of air pollution.
How many have air volume still have when though the filter.
Use of personal-indoor-outdoor sulfur concentrations to estimate the infiltration factor and outdoor exposure factor for individual homes and persons
One goal of the study was to estimate the contribution of outdoor PM2.5 to indoor concentrations. This depends on the infiltration factor F-inf, the fraction of outdoor PM2.5 remaining airborne after penetrating indoors. After confirming with our measurements the findings of previous studies that sulfur has few indoor sources, we estimated an average F-inf for each house based on indoor/outdoor sulfur ratios. These estimates ranged from 0.26 to 0.87, with a median value of 0.55. Since these estimates apply only to particles of size similar to that of sulfur particles (0.06-0.5 mu m diameter), and since larger particles (0.5-2.5 mu m) have lower penetration rates and higher deposition rates, these estimates are likely to be higher than the true infiltration factors for PM2.5 as a whole. In summer when air conditioners were in use, the sulfur-based infiltration factor was at its lowest (averaging 0.50) for most homes, whereas the average F-inf for the other three seasons was 0.62-0.63, Using the daily estimated infiltration factor for each house,we calculated the contribution of outdoor PM2.5 to indoor air concentrations.
In addition to
air conditioning, the following when decorating, essential items are always affects the indoor air quality:
Wood, wood itself is not toxic, but because of its process using urine aldehyde adhesive, so the form of formaldehyde pollution;Especially palm fiber board, density board and particieboard glue content is larger, which contains a lot of formaldehyde.(the finished board type furniture, cabinets using this board more)
Glue: the main components of the family is decorated in the use of glue for formaldehyde, use glue place such as metope grassroots emulsioni paint putty glue, paste board with white latex, the wallpaper glue paste wallpaper.100 – square – meter use glue in more than 100 kg, the bedroom of the national standard of glue content of 1 g/kg, so the bedroom decorate after basic 100 g formaldehyde, according to the three years preceding the standard conversion may exceed bid more than 3 times, almost covered the whole room make bridal chamber gas Chambers.The glue is decorated in possession of pollution sources pollution is the largest proportion.
Paint: because it contains a lot of heavy benzene, so people to paint the strongest perception;Family is decorated in the paint is applied topically, plus the volatilization of paint is quite fast, three days can volatilize harmful substances by more than 70%.So its not the biggest pollution source.It is recommended to use water-based paint replacement (add water dilute, oily paint with water or banana oil dilution) that day can be avoided.
Emulsioni paint, because use emulsioni paint area is very wide, lots of people generally think of emulsioni paint pollution is very heavy;Water-based latex paint is the main difference of other physical quality performance, within one day after brushing can volatilize harmful substances by more than 90% of them, so it can be usually ignored environmental performance indicators.
Cigarette: cigarette smoke gas and particle phase content contains thousands of chemical substances, including 60 has proved or suspected have carcinogenic effect to human body.Strictly, cigarette material includes chemicals, and combustion after the particulate matter.Journal of Tobacco Control once contrast cigarettes and the contribution rate of automotive diesel engine for PM, get the data as follows:
Diesel engine experiment background concentration: PM10 = 15, PM2.5 = 13, PM1 = 7
After an hour: PM10 = 44, PM2.5 = 31, PM1 = 13
Cigarette experimental background concentration: PM10 = 36, PM2.5 = 28, PM1 = 14
After an hour: PM10 = 343, PM2.5 = 319, PM1 = 168
So the indoor smoking bans how important it is.
Breathing: adult quiet breathing during a time of 6.4 seconds, with each inhalation and exhalation gas volume is about 500 ml, in the process of breathing:
Inhalation: 20.96% oxygen and 0.04% carbon dioxide and other gases by 79%
Exhale: 16.4% oxygen and 4.1% carbon dioxide and other gases by 79.5%
So, a breath of 20.5 ml of carbon dioxide, a year a total of 31536000 seconds, so one year exhaled carbon dioxide 101013.75 L.That is to say, 20 square meters bedroom sleep two people, not a night ventilation and ventilation condition is bad, can cause mild carbon dioxide poisoning after five hours.This is also a lot of people feel dizzy after waking up, the more sleep the more tired.
Almost 80 percent of air pollution involving soot that spreads from China over large areas of East Asia — impacting human health and fostering global warming — comes from city traffic and other forms of fossil-fuel combustion, such as home cooking with coal briquettes. That’s the conclusion of a study in ACS’ journal Environmental Science & Technology, which resolves long-standing questions about sources of air pollution responsible for Asia’s infamous atmospheric brown clouds.
Örjan Gustafsson and colleagues from China, South Korea and the United States point out in their study that nobody has been certain about the exact sources of soot, or “black carbon,” air pollution from the People’s Republic of China. People can inhale these tiny particles deep into the lungs, and estimates implicate soot with 500,000 premature deaths annually in China alone. Black carbon in the atmosphere also absorbs sunlight, and scientists think it is second only to carbon dioxide as a factor in global warming. Gustafsson and his team set out to identify the exact sources of black carbon in China.
They describe using a powerful carbon-14 identification method to trace fully four-fifths of the black carbon emitted in China to incomplete combustion of fossil fuel such as coal briquettes used in home cookstoves and automobile and truck exhaust. “To mitigate near-term climate effects and improve air quality in East Asia, activities such as residential coal combustion and city traffic should be targeted,” they conclude.
How to solve or improve indoor air quality?
Install some exhaust fan inside your house;
- Install fresh air system, such as our ER (heat exchanger), AJH (Purifying box), DPT-PM ( purifying blower), BPT( ceiling mounted ventilation fan), APC (window mounted ventilation fan), DPT(quiet cabinet fan), and some outlet.
- Add more air purifier, and so on.
