new fumes question

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New Member
Oct 23, 2007
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Hello everyone,

I am fresh and new to soap making. I had suited up, goggles and all and everything went great. I remember reading one place that after the lye water mixture mixes with the oils, its not nearly as caustic or able to burn. So I gently rinsed off all equipment without gloves but very carefully - its hard to find anything online that addresses clean up

Well all went well. So today I took the lovely soaps out of the mold and cut them into bars, they are now curing on the shelf. Curiosity got the best of me and I decided to see if a small chip bar would lather. I was shocked when my throat started scratching and burning and eyes watered. I immediatly flushed the small bar down the toilet, turned on the bathroom fan and washed my hands off. My hands were not harmed etc, but my nose burned and eyes watered.

Can anyone explain where the bars are this early on in the danger zone? I am curious how much damage an uncured bar can do and it I read wrong that its not as caustic when mixed?
The chemical reaction continues for 24 hours after lye and oils mix. It is still very caustic. You would not want to wash your utensils with bare hands.
Agreed, if you would have left the bar alone to cure chances are better than not it would have been fine and turned out.

There is a reason why they say it needs a minimum of 3 weeks to cure, some recipes need much longer cure time.

The lye was still raw and caustic when you used it, and just like when you first mixed it with your liquid it puts off an 'odor'.
There is an age old debate/discussion that goes on several times a year at every soap forum about how long the saponification process continues after the oils and lye solution are incorporated together to begin the process. I do not think there is an definitive answer. Is the SAP process over in 24 hours; definitely not. Is it over in 48 to 72 hours; probably most of it is. If you use soap that is 72 hours old and you get "burned" something was wrong with your recipe. I cannot definitely say, but after doing this several years, using pH test strips only, I think 95 to 99% of all saponification has occurred after the 48 to 72 hour mark. The continuing "curing" time is for dehydration to take place in the soap. A harder, dryer soap lasts longer, bubbles more when used in the bath.
Forum member NEA just made a fresh batch and posted today that it tested at 9 on the pH scale. That is great for a day old soap. Our skin is around 5.5 to 5.9 pH on the scale for a caucasian. Any soap between 7 to 9 on the pH scale is a safe soap to use as far as saponification is concerned. A 8 or 9 pH soap may be drying due to other factors like to much Coconut Oil or Palm Kernel Oil, too much lye for the SAP values of the oils used, or not taking a decent ly discount of at least 4%, but NOT due to incomplete saponification of oils/lye mixture. Hope this helps some newer ones understand saponification and curing time and what it does for your soap.

Paul.... :wink:

Also, Olive Pomace Oil (what I used in my recipe) supposedly speeds up the saponification process, by helping to incorporate the other oils. Oils of Nature cautions soapmakers to take that into consideration, when adding certain EO's and FO's.

I've read conflicting reports as well. But I guess it doesn't make sense to me that soap should still be going thru the saponification process, after 24 hours. Now, I've only made one batch of soap, so I'm not trying to be an expert. I'm just sharing my thoughts, BASED on what I've researched. I'm open to correction.

Here's what's messin' with my head:
If saponification generates heat, once the soap batter has heated enough to gel, and then goes back to room temperature, I thought "saponification" was done, and the next part is curing the soap, to harden it and make it milder.

I certainly wouldn't expect the soap to be "caustic" to the point of causing red eyes, burning noses and skin — not even after only 24 hours. That doesn't sound right to me. I tried a sample of my soap, straight out of the mold (after 24 hours). It lathered well, and caused no irritation/dryness. Would I use it now? No. I'm going to let it cure for 4 weeks. I want it harder and milder, because I'm planning to hand it out to testers.

In Paul's mold, I could feel the heat, primarily on the lid. His molds insulate so well. It's amazing. The mold never got "hot" to the touch. I don't know how hot it was inside. But the outside was just a nice, very warm temperature. The soap went thru a complete gel, and then it cooled down and I cut it, in 24 hours and took a pH reading. I was not expecting it to be higher than a 9 or 10. I also wasn't expecting the soap to be caustic.
Nea, I'm with you - I'm a shocker for 'testing' a batch straight out of the mold, and I've never had any problem with it. I've certainly never had any kind of fume or irritation issue!
The lye was still raw and caustic when you used it, and just like when you first mixed it with your liquid it puts off an 'odor'

Thank you so much that does make much sense. I think this sliver and it was not a bar but a small test bar if you will, was not quite 24 hours old. I was upstairs in my bathroom and I lathered it under hot water and my throat was scratchy and kept getting more irritated with some fumes, eyes got alittle wattery like when you cut an onion and hands did not burn or get red, just a tad dry the next day. So im guessing like you said this was just the rawness of this bar.

I tested the PH of it today and its a tad less then 8 - so im assuming that it was just the chemical reaction still taking place? I followed instructions entirely and then some.

Paul thank you so much that is a fantastic post, I need to save that for my future reference.

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