Laserfiche WebLink
<br />"" ','" ' <br />. . <br />.. -..,..~- --,-,.':';~",:,~'.,,-,~,::';..~~,-- <br /> <br />,::':,','i:,:',:; <br /> <br />'-.' - .....'".,-~..-._, <br />. , '- " '-,."'-'~""'-" <br />. "::'~~"H'~".~ d~'~~'" >. ~;:::~:u:;~'~:':';;i;~-~,;-~-~;i7/~~:Yd&i~~:,;~~;rS~-i}r <br /> <br />".' <br /> <br />-_._- <br />':"', .-,' <br />: ._-,;...<:::...~~,;,-,_. <br /> <br />- <br /> <br />-"- <br /> <br />- <br /> <br />- <br /> <br />- <br /> <br />- <br /> <br />...... . <br />.' <br /> <br />t"'''''1 <br />. \.JV <br /> <br />Oivision: Air poliution Control Division <br />James H. Lents. Director <br /> <br />E. NITROGEN DIOXIDE EXPOSURE <br /> <br />Of the various oxides of nitrogen. the most important as air pollutants are nitric oxide (NO) and nitrogen dioxide (N02). Nitric oxide and a <br />comparatively small amount of N02 are formed under high teaperature conditions such as those that accompany the burning of fossil fuels. <br />They are emitted from stationary sources such as furnace stacks. boilers, incinerators and vents from certain chemical processes. Most of the <br />NOx produced technologically is in the form of NO, which is subsequelntly oxidized in the atmosphere to the more toxic and irritating >>02. <br /> <br />Ni tragen dioxide (N02) has many biologic effects similar to that of ozone but an equal concentration basis is less toxic. In <br />current N02 levels are slightly below the national ambient standard. Table 11-4 summarizes the health effects of nitrogen dioxide. <br />effects of nitrogen oxides are found in visibility imparement and acid deposition related impacts, <br /> <br />Colorado <br />Welfare <br /> <br />Short-term exposure to N02 can induce respiratory difficulties as well as pulmonary edema. Long-tera exposure to N02 can lead to acute <br />respiratory disease and acute bronchitis. Welfare effects include fading of cloth material. vegetation damage and visibility reduction. <br /> <br />TABLE U-4 <br /> <br />ESTIMATED HEALTH EFFECTS LEVELS FOR NITROGEN DIOXIDE EXPOSURE <br /> <br />EFFECTS <br /> <br />EXPOSURE DURATION <br /> <br />Specific airway resistance increase. Asthmatics <br />reported mild symptomatic effects. Significant <br />decrement in blood gas parameters for both <br />healthy adults and bronchi tics , no changes observed <br />below 2.0 PPM. Significant increase in airway <br />resistance at or above 1.6 PPM. <br /> <br />0.1-5.0 PPM 3 minutes 2 lwurs <br /> <br />No physiologically significant changes in <br />cardiovascular. metabolic or pulmonary <br />function after exercise of up to 60 minutes. <br /> <br />0.6 PPH <br /> <br />2-lIours <br /> <br />Increased inspiratory and expiratory flow <br />resistance. No statistically significant <br />changes in healthy adults pulmonary function <br />tests with the exception of small changes in <br />forced vital capacity. Slight increase in <br />respiratory symptoms above 2.0 PPM'. <br /> <br />1.0-2,0 PPH <br /> <br />for 2-lIours <br /> <br />-23- <br /> <br />- .-...,,;,~j-," ;< .;-;-<,;~.::,,-..,':,,',~;., <br />