The IFRA Standards, explained

What the IFRA Standards are

The International Fragrance Association publishes a set of Standards that say which aroma materials must not be used at all, how much of certain others may appear in a finished product, and what purity a few of them have to meet. They sit inside the IFRA Code of Practice, and they are written by the industry that makes fragrances, for the industry that makes fragrances.

The 51st Amendment is the set in force. It covers 263 Standards. Most of them restrict a material to a maximum concentration, 86 of them prohibit a material outright, and 31 attach a purity or handling requirement to one. A single Standard can do more than one of those things at once.

The thing that confuses most people arriving at this for the first time is that a limit is never a single number. It is a number per category, and the categories are about the finished product a customer buys, not about the perfume oil you blended.

They are not law, and they will still stop you selling

No government wrote the IFRA Standards and no statute anywhere says you must follow them. They bind IFRA members and the members of its national associations directly. Everybody else meets them through other people's paperwork, which in practice is harder to avoid than a law would be.

They reach you through the certificate of conformity your supplier issues with a fragrance oil, through the terms a retailer or a marketplace makes you accept, through what an insurer will cover, and through the contract manufacturer who will not fill a bottle without one. Refuse the Standards and you are not breaking the law; you are simply finding that nobody in the chain will handle your product.

In the European Union they also acquire indirect legal force. The Cosmetics Regulation requires a qualified safety assessor to sign off the product, and an assessor who disregards the industry's own consensus on a sensitizer has to explain why in writing, over their own signature and their own professional indemnity. Very few will.

The three things a Standard can do

Read the type before you read the number, because they answer different questions.

• Prohibition. The material must not be used as a fragrance ingredient. There is no category and no concentration; the answer is no everywhere. Some prohibitions carry a note allowing the material to be present as a natural constituent of something else, up to a stated trace.
• Restriction. A maximum concentration in the finished product, given per category. This is the common case and the one that needs arithmetic.
• Specification. A requirement about the material itself rather than about how much you use: an impurity that must stay under a limit, a peroxide value that must not be exceeded, or a way the material has to be produced or stored. A specification says nothing about dose, and you can breach one while being comfortably under the restriction.

Specifications are the ones that catch people out, because they are a property of the bottle on your shelf rather than of the formula on your screen. A peroxide limit on a citrus oil or a terpene rises as the bottle ages, so a material that met its Standard when it arrived can quietly stop meeting it, with no change to the formula at all.

Twelve categories, eighteen limits

The categories group finished products by how much fragrance reaches skin, where on the body, and whether it stays there. There are twelve of them, but four are split into lettered sub-categories that carry different numbers, so a Standard actually gives eighteen limits.

Two categories behave differently from the rest and it is worth knowing why. Category 1 holds children's toys not because a toy is a lip product but because no exposure data exists for toys, so IFRA places them in the strictest category available. Category 11A and category 12 carry no phototoxicity limits, because 11A is contact without sunlight and 12 is not skin contact at all, which is why a bergamot Standard that looks alarming everywhere else prints no restriction against a candle.

One material, five very different answers

Eugenol is the clove note, and it is restricted for dermal sensitization. Here is the whole of its 51st Amendment restriction, in the categories a small house is most likely to be working in.

Read the shape of that rather than the numbers. The shower gel is allowed almost eight times what the body lotion is allowed, because it is rinsed off within a minute while the lotion sits on a large area of skin all day. Fine fragrance sits between them, because it goes on in small quantity to a small area. The lip balm is tight because the material can be ingested. The candle has no limit at all, because nothing touches skin.

This is why the instinct that fine fragrance is the permissive category is wrong, and why a formula moved from one product type to another has to be reassessed rather than assumed. The most common expensive mistake in a small house is a fragrance oil sold for candles being put into a body product.

How to apply a limit to what you actually blended

Every IFRA limit is a percentage of the finished product. Almost nobody works in the finished product. You work in a concentrate, which is then diluted into alcohol, or into a wax, or into a lotion base. So there is one conversion to do, and getting it backwards is the single most common error in this whole subject.

Suppose you are making an eau de parfum at 20 percent concentrate, and your concentrate contains eugenol. The category is 4, so the limit is 2.5 percent of the finished product. The finished product is one fifth concentrate, so your concentrate may carry up to five times that figure: 12.5 percent eugenol in the concentrate gives exactly 2.5 percent in the bottle.

Take the same concentrate and sell it at 8 percent as an eau de toilette instead, and the concentrate may now carry up to 31.25 percent eugenol. Take it the other way and put that concentrate into a body lotion at 1 percent, and the category becomes 5A with a limit of 0.64 percent of the finished product, which the concentrate clears easily. The formula did not change once. The answer changed three times.

Two things make this harder than the arithmetic suggests. First, a restricted material is very often not on your formula as a line of its own: it arrives as a constituent of a natural. Clove bud oil is the majority eugenol, so a formula with no eugenol line in it can still be far over the limit. Second, if you built the formula from bench dilutions, only the stated fraction of what you weighed is actually material, and the rest is solvent that mostly leaves the sum.

A correct assessment therefore has to look inside every natural on the formula, sum each restricted material across every route it arrives by, and know which of the things you weighed were dilutions. Doing that by hand on a spreadsheet, for 263 Standards, every time a formula changes, is the work this software exists to remove.

Amendments, and the two deadlines they carry

The Standards are revised in amendments, roughly every two years. Each amendment gives two deadlines, and they apply to different fragrances rather than to different obligations.

• New creations. A fragrance briefed after the amendment's information exchange period closes. These get the earlier deadline.
• Existing creations. A fragrance already on the market, or already in development when that period closed. These get the later one, which is the grace period for reformulating something you already sell.

The 51st Amendment was notified on 30 June 2023. Its prohibitions bit on new creations from 30 August 2023 and on existing creations from 30 July 2024. Its restrictions and specifications bit on new creations from 30 March 2024 and on existing creations from 30 October 2025. All four of those dates have passed, so the 51st applies to everything, with no grace period left anywhere in it.

The 52nd Amendment is coming. Its consultation closed on 12 June 2026 and formal notification is expected around the end of 2026. The proposals published for consultation included a substantial number of new restrictions, revisions to existing ones, and the folding of the furocoumarin policy into a single Standard. Nothing in it is in force yet, and nothing in it should be treated as final until IFRA notifies it.

One detail in the deadlines is easy to misread: compliance is measured against the date the fragrance mixture is placed on the market, not the date the finished consumer product reaches a shelf. A perfume oil sold to a candle maker is on the market the day it is sold.

What to keep, and for how long

An IFRA assessment is not a permanent property of a formula. It is a statement about one formula, at one category, against one amendment, on one day. Three of those four can change without you touching the formula.

So the assessment worth keeping is the one that was true when the batch was made, stored with the batch rather than recalculated later. If a question about a bottle arrives in four years, and it will, the answer has to be what the rules said when that bottle was filled. Recomputing it against today's amendment answers a question nobody asked.

How Orris Bench handles this

Orris Bench assesses a formula against the IFRA Standards at the category it will actually be sold in, before it is made, while changing it is still cheap. It looks inside the naturals on the formula and sums each restricted material across every route it arrives by, including the ones that are constituents of something else and the ones that came in through a bench dilution.

The verdict names what it checked. Where something on the formula has no composition behind it, the assessment says it cannot verify that line rather than passing it quietly, because a clean result that was only clean because nobody looked is worse than no result at all. Prohibitions, restrictions and specifications are handled as the different questions they are, and the amendment each answer came from is recorded with it.

The verdict is stored with the batch at the time of making, so the record keeps saying what was true on the day rather than being quietly rewritten by the next amendment. Amendments are held side by side rather than overwritten, so a batch made under the 49th still resolves against the 49th.

Sources

The category descriptions are from Table 11 of the IFRA Standards Guidance. The eugenol figures and the Standard counts are read from the 51st Amendment Standards library and its published overview. The amendment dates are IFRA's own notification of the 51st Amendment of 30 June 2023, and IFRA's published consultation record for the 52nd. This page is written for people who make fragrances and it is not legal advice; before you rely on a number, check it against the current IFRA Standards Library, which IFRA publishes free.