{"id":26,"date":"2020-08-11T03:04:04","date_gmt":"2020-08-11T03:04:04","guid":{"rendered":"https:\/\/dieselemissions.com.au\/?page_id=26"},"modified":"2020-08-11T03:07:14","modified_gmt":"2020-08-11T03:07:14","slug":"nitrogen-dioxide","status":"publish","type":"page","link":"https:\/\/dieselemissions.com.au\/?page_id=26","title":{"rendered":"Nitrogen dioxide"},"content":{"rendered":"\n<p>NO<sub>2<\/sub> is an irritant and oxidant which can damage cell membranes and proteins. It has been linked to a range of adverse health effects, including asthma and cancer, but the most consistent association has been found with respiratory outcomes.<\/p>\n\n\n\n<p>NO<sub>2<\/sub> is predominantly a secondary pollutant, its major atmospheric source being the oxidation of NO emitted from combustion sources &#8211; notably road vehicle exhaust. However, some NO<sub>2<\/sub> is emitted directly from vehicles, and this is commonly referred to as \u2018primary NO<sub>2<\/sub>\u2019. Emissions of NOx from vehicle exhaust are regulated at type approval, but NO<sub>2<\/sub> emissions <em>per se <\/em>are not.<\/p>\n\n\n\n<p>Analyses have indicated that a significant proportion of ambient NO<sub>2<\/sub> must be emitted directly from vehicle exhaust, and that the direct road traffic contribution to ambient NO<sub>2<\/sub> has increased in recent years.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p><em>Two contributing factors have been cited<\/em><\/p><\/blockquote>\n\n\n\n<p>(i) Diesel vehicles emit more NO<sub>x<\/sub> than petrol vehicles, and with a larger proportion of NO<sub>2<\/sub> in NO<sub>x<\/sub>.<\/p>\n\n\n\n<p>(ii) The average value of NO<sub>2<\/sub> in diesel exhaust is increasing. This appears to be linked to the growth in the use of specific after-treatment technologies in modern diesel vehicles which involve <em>in situ <\/em>generation of NO<sub>2<\/sub>, such as catalytically regenerative particle filters.<\/p>\n\n\n\n<p>Background concentrations of ozone are also increasing. As the ozone concentration increases the amount of NO converted to NO<sub>2<\/sub> increases.<\/p>\n\n\n\n<p>Furthermore, it seems likely that real-world NO<sub>x<\/sub> emissions from road vehicles are not decreasing as rapidly as models are predicting. Whilst this does not, in itself, affect actual NO<sub>2<\/sub> concentrations, it does suggest that NO<sub>x<\/sub> controls have not been sufficiently stringent, or that vehicles are not performing as expected.<\/p>\n\n\n\n<p>The overall consequence is that there is now a great deal of interest in the tighter regulation of NO<sub>x<\/sub> and NO<sub>2<\/sub> emissions from diesel vehicles and the effects of different after-treatment devices. Direct-injection petrol engines with after-treatment technologies will also have an important impact on NO<sub>x<\/sub> emissions in the future.<\/p>\n\n\n\n<div class=\"wp-block-buttons is-layout-flex wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button\"><a class=\"wp-block-button__link\" href=\"https:\/\/autotest.net.au\/product\/autotest-gas-analyser-opacity-meter\/\">See Testing Products with Auto<em>Test<\/em><\/a><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>NO2 is an irritant and oxidant which can damage cell membranes and proteins. It has been linked to a range of adverse health effects, including asthma and cancer, but the most consistent association has been found with respiratory outcomes. NO2 is predominantly a secondary pollutant, its major atmospheric source being the oxidation of NO emitted &hellip; <\/p>\n<p class=\"link-more\"><a href=\"https:\/\/dieselemissions.com.au\/?page_id=26\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Nitrogen dioxide&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-26","page","type-page","status-publish","hentry","entry"],"_links":{"self":[{"href":"https:\/\/dieselemissions.com.au\/index.php?rest_route=\/wp\/v2\/pages\/26","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dieselemissions.com.au\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/dieselemissions.com.au\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/dieselemissions.com.au\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dieselemissions.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=26"}],"version-history":[{"count":2,"href":"https:\/\/dieselemissions.com.au\/index.php?rest_route=\/wp\/v2\/pages\/26\/revisions"}],"predecessor-version":[{"id":30,"href":"https:\/\/dieselemissions.com.au\/index.php?rest_route=\/wp\/v2\/pages\/26\/revisions\/30"}],"wp:attachment":[{"href":"https:\/\/dieselemissions.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=26"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}