combining fragrance oils and safety limits

[KimT2au]

Hi all

I hope I have posted in the correct forum, I was not sure if the fragrance oil/fragrance oil review forum was more appropriate or not. If I wish to use more than one fragrance oil what do I do about the IFRA recommendations? If, for example, fragrance A has a recommended limit of 5% and fragrance B has a limit of 3 %, do I add each fragrance up to each one's limit or does the total of the fragrances oils have to fall below the 3% limit? What if the fragrances have common chemicals, by combining them am I potentially overloading on those chemicals? I am not sure if I am explaining that very well or not.

Kim moved

 

[msunnerstood]

Ive done that before and I always use the lower of the percentages. so i put 3% in soap calc and then use half of the total amount for each oil.

 

[DeeAnna]

There's a practical limit on how much scent one can put in a product. Based on practical experience, I've found about 8% total fragrance is the upper limit in soap. Much more than that, the fragrance weeps out. About 6% is a reliable top limit.

IRFA recommendations don't take this into account ... you'll find IRFAs as high as 100%, for example. If I wanted to use 2 scents, and 1 had an IRFA of 2% and the other was 25%, I would consider 2% of the 1st (if I used it at all) and 3% or 4% of the 2nd for a total of 5% to 6%. But then I'd check the resulting blend ... does it smell right? Too strong? Too weak? And adjust from there.

That said, I don't generally use scents with IRFA limits below 6% and preferably much higher. I like scent, but I also want my soap to be as safe as possible, so it makes no sense to me to use scents that are borderline. That goes for EOs as well as FOs