I must first apologise, because I know this has been asked about a million times, and I've read numerous threads, but the more I read, the more confused I am.

I'm trying to calculate how much fragrance oil it's safe for me to use.

Soapcalc defaults to 0.5 oz ppo, which works out to just over 3% - I've used this, and had a nice smelling soap, not crazy strong, but strong enough for my liking. From the threads I've read, between 0.5 and 1oz ppo seems to be pretty standard.

On checking the manufacturer's recommendations, they say usage rate is 0.01% in a wash-off product. This seems like a very tiny amount. 0.01% is one-tenth of a percent, right? Am I missing something? Is my maths wrong?

I'm in the UK, looking in particular at FOs supplied by Just A Soap. Any comments or ideas anyone has would be really useful, because I just can't understand how FO at 0.01% can possibly be strong enough.

Thanks in advance.

Well, I've answered my own question - sort of.

I've now found a separate document detailing IFRA usage limits, which for the FO I'm looking at, is 9.27%.

The allergen information states usage in finished product as 0.01% though.

I'm trying to calculate how much fragrance oil it's safe for me to use.

Soapcalc defaults to 0.5 oz ppo, which works out to just over 3% - I've used this, and had a nice smelling soap, not crazy strong, but strong enough for my liking. From the threads I've read, between 0.5 and 1oz ppo seems to be pretty standard.

On checking the manufacturer's recommendations, they say usage rate is 0.01% in a wash-off product. This seems like a very tiny amount. 0.01% is one-tenth of a percent, right? Am I missing something? Is my maths wrong?

I'm in the UK, looking in particular at FOs supplied by Just A Soap. Any comments or ideas anyone has would be really useful, because I just can't understand how FO at 0.01% can possibly be strong enough.

Thanks in advance.

Well, I've answered my own question - sort of.

I've now found a separate document detailing IFRA usage limits, which for the FO I'm looking at, is 9.27%.

The allergen information states usage in finished product as 0.01% though.

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