The base crossed a threshold

How it happens

A wintergreen note gets doubled because customers liked it. A carrier is swapped for a cheaper isoparaffin. A blend is concentrated so a smaller bottle throws as well as a larger one. Each is a reasonable decision and each can move a percentage by weight.

Hydrocarbons sum across components

The rule says the total is the sum of the percentages by weight of the individual hydrocarbon components, so three carriers at 4 percent each are over the line while none of them looks like a problem on its own.

The definition is narrower than it sounds

Hydrocarbons there are substances consisting solely of carbon and hydrogen. Glycols and esters are not hydrocarbons under that definition, so a base built on them is answering a different question. Check what your carrier actually is.

Nothing in the supply chain will tell you

Bottles, closures and labels all arrive the same whatever the formula says. The only place this is caught is your own formula sheet, which is the argument for recomputing it on every reformulation.

And the consequence lands on the cheapest item

The refill bottle, usually. It is the format with free-flowing liquid and a closure the customer opens, so a threshold crossing shows up there first and most expensively.

Recompute, do not reason

These are arithmetic tests on a formula you already have written down. Running the numbers again takes minutes; deciding by recollection that nothing has changed much is how the original figure stops being true.

Version the formula like code

A dated formula sheet with the computed percentages beside it, one version per change. That is the whole discipline, and it is what makes the question “has anything crossed a line” answerable in minutes rather than by memory.

References