{"id":12015,"date":"2020-09-10T13:11:38","date_gmt":"2020-09-10T05:11:38","guid":{"rendered":"https:\/\/smartairfilters.com\/?p=12015"},"modified":"2023-08-24T15:39:53","modified_gmt":"2023-08-24T07:39:53","slug":"coronavirus-survive-purifier-hepa-filter","status":"publish","type":"post","link":"https:\/\/smartairfilters.com\/en\/blog\/coronavirus-survive-purifier-hepa-filter\/","title":{"rendered":"How Long can the Coronavirus Survive on HEPA Filters?"},"content":{"rendered":"

Studies have found air purifiers with HEPA filters are highly effective at filtering out COVID-19 coronavirus<\/a> and even smaller viruses<\/a>.<\/p>\n\n\n\n

But viruses can remain on surfaces for scarily long periods of time. It’s led to incredible-sounding headlines about how long viruses last.<\/p>\n\n\n

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\"Covid<\/figure><\/div>\n\n\n

The thought of a virus stuck in an air purifier’s HEPA filter sounds scary. But a \u201cdetectable\u201d virus is very different from a \u201cviable\u201d virus. A viable virus is one that’s alive and still able to infect someone. “Detectable” viruses are just that – detectable, but not necessarily viable.<\/p>\n\n\n\n

How Long Can Viruses Last on HEPA Filters?<\/h2>\n\n\n\n

To answer this question, it’s important we look at how long viruses remain viable on HEPA filters. It’s likely that inactive (“dead”) viruses will remain stuck in HEPA filters for a very long time. But what’s more important is how long are they active and able to re-infect.<\/p>\n\n\n\n

Researchers at the University of Hong Kong <\/span>tested how long viruses<\/a> remain viable <\/span>on 6 different surfaces. They sprayed the H1N1 flu virus on common household materials including plastic, wood, and steel, and tested viability up to 24 hours.<\/p>\n\n\n

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\"H1N1<\/figure><\/div>\n\n\n

Unfortunately, they didn\u2019t test any HEPA filter material. But they tested something fairly similar: J-cloth material. It turns out this J-cloth material is actually surprisingly similar to the <\/span>electrostatic material<\/a> used in HEPA filters.<\/p>\n\n\n

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\"J-cloth<\/figure><\/div>\n\n\n

For the HEPA-like J-Cloth material, the tests found that the virus was completely non-viable in less than 5 hours.<\/p>\n\n\n

\n
\"Influenza<\/figure><\/div>\n\n\n

The H1N1 virus remained viable the longest on hard, non-porous surfaces like stainless steel and plastic. However, the flu was non-viable in under 10 hours for even the worst surface\u2013the stainless steel. The researchers concluded that the H1N1 is \u201clikely to survive up to a few hours.\u201d<\/p>\n\n\n

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\"Viruses<\/figure><\/div>\n\n\n

Researchers tested<\/a> the viability of SARS-CoV-2 on masks. This is highly relevant because many HEPA filters are made out of<\/a> the same plastic fibers as masks. The data showed that 50% of the virus “died” in 80 minutes. It was 99.9% inactive after 13 hours. <\/p>\n\n\n

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\"\"<\/figure><\/div>\n\n\n

Another set of scientists in the UK<\/a> tested the viability of a range of viruses on HEPA filters, including Bacillus atrophaeus and MS-2 coliphage. They placed the viruses on the HEPA filter and then blew air through the filter at a constant rate to simulate the usage of the HEPA filter.<\/p>\n\n\n

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\"Survival<\/figure><\/div>\n\n\n

Their data found that the majority of the viruses survived no longer than 2 days. However, the MS-2 coliphage virus \u2013 a non-enveloped virus that has been shown to survive longer than an enveloped virus \u2013 was able to survive up to 6 days. (The COVID-19 coronavirus is an enveloped virus, not like the MS-2 coliphage virus).<\/p>\n\n\n\n

It the Same for HEPAs With The Covid-19 Virus?<\/h2>\n\n\n\n

The study above is for H1N1 (influenza A), not the coronavirus.  There\u2019s little data available specifically on how long the Covid-19 coronavirus lasts.<\/p>\n\n\n\n

The CDC says that the coronavirus <\/span>may remain viable for hours to even days<\/a>. A <\/span>recent study<\/a> <\/span>(that has not been formally published yet) tested the viability of the new coronavirus (HCoV-19) and the \u201cold\u201d coronavirus, SARS (SARS-CoV-1). They sprayed the two viruses on plastic, stainless steel, copper, and cardboard.<\/p>\n\n\n

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\"Coronavirus<\/figure><\/div>\n\n\n

They did not test HEPA filters or cloth materials this time. But the closest material to a HEPA filter surface was cardboard. It took 48 hours for the coronavirus to be completely non-viable on cardboard. On stainless steel, a tiny amount of viable coronavirus remained at 72 hours, That\u2019s 7 times longer than the earlier study found for H1N1.<\/p>\n\n\n\n

<\/p>\n\n\n

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\"How<\/figure><\/div>\n\n\n

However, it’s important to remember that these tests were done in laboratory conditions, sometimes with very high doses of viruses that aren’t expected to be seen in real-world circumstances. This means these numbers may be exaggerated, as explained in one paper on the exaggerated risk of COVID-19 transmission<\/a>.<\/p>\n\n\n\n

Based on this, it’s unlikely the COVID-19 virus would last more than a few hours on HEPA filter surfaces. However, it’s always good to err on the side of caution. Based on these two studies, a very conservative amount of time it would take to kill the COVID-19 virus on HEPA filters would be 48-72 hours. Therefore, it is important to wear gloves or wash hands immediately after when replacing HEPA filters or cleaning an air purifier.<\/p>\n\n\n

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\"How<\/figure><\/div>\n\n
Bottom Line<\/div>
Bottom Line: How Long can the COVID-19 Coronavirus Survive on HEPA Filters<\/div>
The coronavirus, SARS, and influenza A viruses typically die in under 48 hours, across a range of surfaces. A hardy, non-enveloped virus (MS-2 coliphage) was able to survive up to 6 days on HEPA filters. However, the coronavirus \u2013 being an enveloped virus \u2013 is unlikely to last this long. A reasonable estimate for the survival of the coronavirus on HEPA filters is 48 hours, with 72 hours being a conservative number.<\/span><\/div>
Smart Air<\/div><\/div>","protected":false},"excerpt":{"rendered":"

Studies have found air purifiers with HEPA filters are highly effective at filtering out COVID-19 coronavirus and even smaller viruses. But viruses can remain on surfaces for scarily long periods of time. It’s led to incredible-sounding headlines about how long viruses last. The thought of a virus stuck in an air … <\/p>\n

Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":12019,"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":[190,469],"tags":[283,457,528,487,582,444,455],"class_list":["post-12015","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-air-purifiers","category-coronavirus","tag-air-purifier","tag-bacteria","tag-coronavirus","tag-covid-19","tag-hepa","tag-hepa-filter","tag-virus","resize-featured-image"],"acf":[],"_links":{"self":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/12015","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\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/comments?post=12015"}],"version-history":[{"count":10,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/12015\/revisions"}],"predecessor-version":[{"id":27355,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/posts\/12015\/revisions\/27355"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/media\/12019"}],"wp:attachment":[{"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/media?parent=12015"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/categories?post=12015"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/smartairfilters.com\/en\/wp-json\/wp\/v2\/tags?post=12015"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}