{"id":407,"date":"2015-01-13T08:24:53","date_gmt":"2015-01-13T00:24:53","guid":{"rendered":"http:\/\/smartairfilters.com\/cn\/?p=407"},"modified":"2020-07-15T11:55:41","modified_gmt":"2020-07-15T03:55:41","slug":"does-adding-carbon-reduce-particle-effect","status":"publish","type":"post","link":"https:\/\/smartairfilters.com\/en\/blog\/does-adding-carbon-reduce-particle-effect\/","title":{"rendered":"Does Adding a Carbon Layer Reduce Particulate Effectiveness?"},"content":{"rendered":"

I recently published tests showing that carbon actually removes VOCs<\/a>. But adding that carbon layer raises a question: adding carbon means the fan has to power through yet another layer of resistance. Does that make purifier less effective at removing particulates?<\/p>\n

Test Method<\/h3>\n

To test this question, I ran 10 room tests with the Cannon<\/a>\u00a0and 10 tests with the Original DIY<\/a> in the same 15m2 Beijing apartment as\u00a0my earlier tests without a carbon layer<\/a>.<\/p>\n

 <\/p>\n

\"Dylos<\/p>\n

 <\/p>\n

I measured how much particulate it removed with a Dylos particle counter<\/a> and compared the particle counts (1) before I turned on the purifier at night and (2) the average of the last four hours before I woke up in the morning.<\/p>\n

 <\/p>\n

\"Air<\/p>\n

 <\/p>\n

Carbon vs. HEPA Results<\/h3>\n

With the additional charcoal layer, the Cannon<\/a> particulate effectiveness dropped 1-2%. Thus,\u00a0charcoal has a very minor negative effect on the Cannon.<\/p>\n

\"DIY<\/p>\n

However, the Original DIY<\/a> had a harder time powering through the extra layer. Its 0.5 micron effectiveness dropped 19%, and 2.5 micron effectiveness dropped 15%.<\/p>\n

\"DIY<\/p>\n

Conclusion: Carbon Tips<\/h3>\n

For people who need carbon (and that may\u00a0not be everyone<\/a>), I would recommend adding the carbon<\/a> to the Cannon, but I would think twice about adding carbon to the Original. One workaround is to have one Original fan running with a HEPA and another running with a carbon filter.<\/p>\n

As always, I\u2019m posting the raw data and more details on the test for fellow nerds below.<\/p>\n

<\/p>\n

Data: Cannon<\/h3>\n

The previous\u00a0Cannon<\/a>\u00a0test data is in\u00a0my earlier post<\/a>. The raw data for the 10 new tests of the\u00a0Cannon<\/a>\u00a0+ carbon<\/a> +\u00a0HEPA<\/a>\u00a0are here:<\/p>\n

\"3\"<\/p>\n

\"4\"<\/p>\n

\"5\"<\/p>\n

\"6\"<\/p>\n

\"7\"<\/p>\n

Over the 10 testing days, outdoor air pollution went down significantly on 6 days\u2013poor luck! To test whether that affected the overall estimate, I isolated the three testing days with changes in outdoor PM2.5 concentration of less than 10 micrograms.<\/p>\n

For those three days, the 0.5 micron results were still 95%. The 2.5 micron results were 93%, which is 2% lower than in the overall tests. Thus, the overall estimate seems to be little affected by outdoor fluctuations when averaged over all of the tests.<\/p>\n

Data: Original DIY<\/h3>\n

Below is the data for 10 tests with the Original DIY.<\/p>\n

\"8\"<\/p>\n

\"9\"<\/p>\n

\"10\"<\/p>\n

\"11\"<\/p>\n

\"12\"<\/p>\n

One day (12\/21) was an outlier because the outdoor AQI almost tripled during the test. Thus, I calculated the average with and without that outlier removed. With the outlier included, .5 microns effectiveness was 5% lower and 2.5 micron effectiveness was 2% lower.<\/p>","protected":false},"excerpt":{"rendered":"

I recently published tests showing that carbon actually removes VOCs. But adding that carbon layer raises a question: adding carbon means the fan has to power through yet another layer of resistance. Does that make purifier less effective at removing particulates? Test Method To test this question, I ran 10 … <\/p>\n

Read more<\/a><\/p>\n","protected":false},"author":1035,"featured_media":5144,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_relevanssi_hide_post":"","_relevanssi_hide_content":"","_relevanssi_pin_for_all":"","_relevanssi_pin_keywords":"","_relevanssi_unpin_keywords":"","_relevanssi_related_keywords":"","_relevanssi_related_include_ids":"","_relevanssi_related_exclude_ids":"","_relevanssi_related_no_append":"","_relevanssi_related_not_related":"","_relevanssi_related_posts":"","_relevanssi_noindex_reason":"","footnotes":""},"categories":[259,258],"tags":[298,256,319,294],"class_list":["post-407","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-filters","category-vocs","tag-activated-carbon","tag-diy","tag-diy-purifier","tag-vocs","resize-featured-image"],"acf":[],"_links":{"self":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/407","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/users\/1035"}],"replies":[{"embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/comments?post=407"}],"version-history":[{"count":12,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/407\/revisions"}],"predecessor-version":[{"id":11455,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/407\/revisions\/11455"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/media\/5144"}],"wp:attachment":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/media?parent=407"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/categories?post=407"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/tags?post=407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}