<p>On paper, IPA is very flammable, and the vapours are more so, but in practice this mostly applies to a flashover situation where liquid IPA is heated rapidly. Such as being spilled on a hotplate, or where there is a significant buildup of vapour in an oxygen rich environment hat is exposed to a sudden naked flame.</p>
<p>If you spilled IPA directly onto your Power Supply and it went through the vents and touched something very hot, causing the liquid IPA to vaporize, then it would be a dangerous situation.</p>
<p>Other parts of your printer, such as the bed would not heat the IPA fast enough for it to become a fire hazard unless the concentrations were extreme. You would notice such levels as they would make you feel light headed or give you a headache.</p>
<p>The TLDR is that what you're doing is not especially hazardous, and simply opening a window would be enough to render the hazard level minimal. I'd be more worried about the effect of the IPA on your skin, or breathing in the fumes, than I would about the fire risk.</p>
<p>Printers would only really be dangerous if you had a print farm and were doing this on multiple printers until the fumes built up. Even then you're more at risk from inhalation.</p>
<p>This comes from my industrial level hazardous substances training.</p>

CC BY-SA 4.0
2024-09-24T19:08:24.393Z
2024-09-24T19:08:24.393Z
Aaargh Zombies
<p>The vapor is flammable. You should avoid any ignition source (open flame such as match, candle, or cigarette) in close proximity. The amount of vapor released is only dangerous in a very limited space around where the alcohol is used (a few inches or so), where it is concentrated. Any further away and it is diluted by the atmosphere in the room.</p>
<p>It's no more dangerous around your 3D printer than it is if you're using it to clean an area of your skin. I spray my build plate and wipe it with a lint-free shop towel before printing.</p>

CC BY-SA 4.0
2024-09-22T13:58:12.027Z
2024-09-22T13:58:12.027Z
Ken White
<p>I'm using 99.9% <a href="https://www.3djake.uk/3djake/isopropyl-alcohol" rel="nofollow noreferrer">Isopropyl Alcohol</a> to clean some parts like the build plate. This <a href="https://www.safetyandhealthmagazine.com/articles/21425-vapors-from-isopropyl-alcohol-can-irritate-ignite-hazard-alert" rel="nofollow noreferrer">Safety+Health</a> page states that isopropyl alcohol vapors can be hazardous and ignite. They advise to ensure <em>&quot;proper ventilation&quot;</em>.</p>
<p>My question is whether it is a bad idea to use isopropyl alcohol in close proximity to a 3D printer that is actively printing? The printer is fully enclosed so there is no risk of direct contact with the liquid. I just put a little alcohol on a piece of cloth and close the lid to avoid unnecessary vapors. I don't know what <em>&quot;proper ventilation&quot;</em> exactly means; at least the door of my workshop is open at all times.</p>
<p>I think I'm being a bit overcautious, but better safe than sorry.</p>

<safety>
Are isopropyl alcohol vapors dangerous near a 3D printer?
Velvet
# Are isopropyl alcohol vapors dangerous near a 3D printer?

(Asked by: username_0 on 2024-09-08)

I'm using 99.9% [Isopropyl Alcohol](https://www.3djake.uk/3djake/isopropyl-alcohol) to clean some parts like the build plate. This [Safety+Health](https://www.safetyandhealthmagazine.com/articles/21425-vapors-from-isopropyl-alcohol-can-irritate-ignite-hazard-alert) page states that isopropyl alcohol vapors can be hazardous and ignite. They advise to ensure *"proper ventilation"*.

My question is whether it is a bad idea to use isopropyl alcohol in close proximity to a 3D printer that is actively printing? The printer is fully enclosed so there is no risk of direct contact with the liquid. I just put a little alcohol on a piece of cloth and close the lid to avoid unnecessary vapors. I don't know what *"proper ventilation"* exactly means; at least the door of my workshop is open at all times.

I think I'm being a bit overcautious, but better safe than sorry.

**Tags:** safety

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## 2 answers

### Answer by username_2 on 2024-09-22. Score: 4 | Accepted answer

The vapor is flammable. You should avoid any ignition source (open flame such as match, candle, or cigarette) in close proximity. The amount of vapor released is only dangerous in a very limited space around where the alcohol is used (a few inches or so), where it is concentrated. Any further away and it is diluted by the atmosphere in the room.

It's no more dangerous around your 3D printer than it is if you're using it to clean an area of your skin. I spray my build plate and wipe it with a lint-free shop towel before printing.


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### Answer by username_1 on 2024-09-24. Score: 4

On paper, IPA is very flammable, and the vapours are more so, but in practice this mostly applies to a flashover situation where liquid IPA is heated rapidly. Such as being spilled on a hotplate, or where there is a significant buildup of vapour in an oxygen rich environment hat is exposed to a sudden naked flame.

If you spilled IPA directly onto your Power Supply and it went through the vents and touched something very hot, causing the liquid IPA to vaporize, then it would be a dangerous situation.

Other parts of your printer, such as the bed would not heat the IPA fast enough for it to become a fire hazard unless the concentrations were extreme. You would notice such levels as they would make you feel light headed or give you a headache.

The TLDR is that what you're doing is not especially hazardous, and simply opening a window would be enough to render the hazard level minimal. I'd be more worried about the effect of the IPA on your skin, or breathing in the fumes, than I would about the fire risk.

Printers would only really be dangerous if you had a print farm and were doing this on multiple printers until the fumes built up. Even then you're more at risk from inhalation.

This comes from my industrial level hazardous substances training.


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