{"id":4868,"date":"2021-03-22T00:43:49","date_gmt":"2021-03-22T00:43:49","guid":{"rendered":"http:\/\/mocktheorytest.com\/resources\/?p=4868"},"modified":"2023-08-24T23:46:29","modified_gmt":"2023-08-24T23:46:29","slug":"how-do-breathalysers-work","status":"publish","type":"post","link":"https:\/\/mocktheorytest.com\/resources\/how-do-breathalysers-work\/","title":{"rendered":"How do breathalysers work?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">When a person drinks alcohol, some of that alcohol is breathed out as the body metabolises it. This can be measured using a breathalyser and it gives a pretty accurate indication of how much alcohol is in a person&#8217;s blood. The more alcohol in your blood, the more affected you are by it &#8211; slower reactions, more difficult to concentrate, and so on.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Breathalysers are used because driving with excess blood alcohol, or &#8216;<a href=\"https:\/\/www.gov.uk\/government\/statistical-data-sets\/reported-drinking-and-driving-ras51#drink-drive-accidents-and-casualties\">drink driving<\/a>&#8216; causes significant social harm. They provide the first line of evidence (backed up with an evidential blood test) that a person is driving drunk, so that that person can be prosecuted.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">There are three ways that breathalysers work:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Infrared spectroscopy: Infrared light waves from a broadband infrared beam passes through a sample chamber onto a spinning filter wheel. IR light is partially absorbed by the molecules of alcohol. If you can figure out how much is absorbed, you can work out the blood alcohol content.<\/li><li>Fuel cell sensors oxidise the alcohol in the sample. As it&#8217;s oxidised, acetic acid, protons and electrons are given off. The electrical current from the electrons is measured and that gives the blood alcohol content.<\/li><li>Semiconductor oxide-based testing uses an ethanol-specific sensor. The sample is bubbled through one of two glass vials of the chemical reagent. The difference in the two samples is then compared to determine the BAC.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">How do you use a breathlyser?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A basic test may be conducted with the police officer holding the unit while you speak towards it. This gives a quick indication of zero alcohol, some alcohol (but below the legal limit) and some alcohol (possibly above the legal limit). If you register the latter, you&#8217;ll be asked to use a calibrated detection unit which will involve you blowing into a tube until enough breath can be collected.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">When is a breathlyser used?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If a police officer stops you and suspects you have been drinking, you may be asked to provide a breath alcohol reading using a breathalyser. If you fail that test you will be required to go to a police station with the officer and take an evidential breath test or blood alcohol test.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If you refuse the test you can be convicted of an offence that is the equivalent of being convicted with a BAC above the legal limit.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What affects a person&#8217;s BAC?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A person&#8217;s blood alcohol level is affected by several factors:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>How much food they have eaten recently<\/li><li>What type of food they have eaten recently<\/li><li>How much liquid other than alcohol they have consumed<\/li><li>How much alcohol by volume they have consumed<\/li><li>The amount of body fat they carry<\/li><li>Their metabolism<\/li><li>Their gender<\/li><li>Their genetics<\/li><li>Whether the alcohol was fizzy or flat (alcohol in fizzy drinks is absorbed quicker)<\/li><li>Whether the person is menstruating.<\/li><\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">How quickly can your blood alcohol concentration become over the limit?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If you drink concentrated alcohol on an empty stomach, you can be over the limit in as little as 10 minutes.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>When a person drinks alcohol, some of that alcohol is breathed out as the body metabolises it. This can be measured using a breathalyser and it gives a pretty accurate indication of how much alcohol is in a person&#8217;s blood.<span class=\"ellipsis\">&hellip;<\/span><\/p>\n<div class=\"read-more\"><a href=\"https:\/\/mocktheorytest.com\/resources\/how-do-breathalysers-work\/\">Read more &#8250;<\/a><\/div>\n<p><!-- end of .read-more --><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"footnotes":""},"categories":[2],"tags":[228],"class_list":["post-4868","post","type-post","status-publish","format-standard","hentry","category-advice","tag-alcohol"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>How do breathalysers work? - Highway Code Resources<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/mocktheorytest.com\/resources\/how-do-breathalysers-work\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"How do breathalysers work? - Highway Code Resources\" \/>\n<meta property=\"og:description\" content=\"When a person drinks alcohol, some of that alcohol is breathed out as the body metabolises it. This can be measured using a breathalyser and it gives a pretty accurate indication of how much alcohol is in a person&#8217;s blood.&hellip;Read more &#8250;\" \/>\n<meta property=\"og:url\" content=\"https:\/\/mocktheorytest.com\/resources\/how-do-breathalysers-work\/\" \/>\n<meta property=\"og:site_name\" content=\"Highway Code Resources\" \/>\n<meta property=\"article:published_time\" content=\"2021-03-22T00:43:49+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2023-08-24T23:46:29+00:00\" \/>\n<meta name=\"author\" content=\"Darren Cottingham\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Darren Cottingham\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/mocktheorytest.com\\\/resources\\\/how-do-breathalysers-work\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/mocktheorytest.com\\\/resources\\\/how-do-breathalysers-work\\\/\"},\"author\":{\"name\":\"Darren Cottingham\",\"@id\":\"https:\\\/\\\/mocktheorytest.com\\\/resources\\\/#\\\/schema\\\/person\\\/5035e20b782db0f2d6f2466549452e48\"},\"headline\":\"How do breathalysers work?\",\"datePublished\":\"2021-03-22T00:43:49+00:00\",\"dateModified\":\"2023-08-24T23:46:29+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/mocktheorytest.com\\\/resources\\\/how-do-breathalysers-work\\\/\"},\"wordCount\":507,\"publisher\":{\"@id\":\"https:\\\/\\\/mocktheorytest.com\\\/resources\\\/#organization\"},\"keywords\":[\"alcohol\"],\"articleSection\":[\"Advice\"],\"inLanguage\":\"en-US\"},{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/mocktheorytest.com\\\/resources\\\/how-do-breathalysers-work\\\/\",\"url\":\"https:\\\/\\\/mocktheorytest.com\\\/resources\\\/how-do-breathalysers-work\\\/\",\"name\":\"How do breathalysers work? 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