How To Read An IFRA Certificate: Simple Guide For UK Home Fragrance Makers

IFRA certificates look terrifying at first sight. Lots of tables, fine print and numbers that seem to make no sense. The good news is that for home fragrance makers you only need a few key parts of the certificate to work out what you can safely use.

This guide walks you through how to read an IFRA certificate in real English so you can find your correct maximum percentages.

What an IFRA certificate actually tells you

IFRA certificates do one main job. They tell you the maximum amount of that fragrance you can safely use in different product types.

They do not tell you:

• how strong the scent will be in wax
• whether your candle will burn well
• whether your label is CLP compliant
• whether your packaging is correct

They purely tell you the usage limits. That is all. Important, but not the full picture.

Where to find the category on an IFRA certificate

IFRA splits products into categories . For example:

• Category 12 is usually for candles and wax melts
• Category 10A is often for reed diffusers
• Category 10B can include room sprays and air freshener sprays
• Other categories cover things like body products, hair, face and so on

On the certificate, you will see a table that lists each category with a brief description. Your first job is to match your product to the correct category.

Example:

• You make a wax melt. You look for Category 12 and read the description to confirm it fits.
• You make a reed diffuser. You look for Category 10A and confirm it is for non skin, non spray, air freshener type products.
• You make a room spray. You look for Category 10B and confirm it fits the description for spray air fresheners.

Once you know your category, you can ignore the others for that product and focus on the line that applies.

Where to find the maximum safe percentage

On the same table, you will see a column with percentages. This is the maximum level of fragrance allowed for each category.

For example, your IFRA certificate might say:

• Category 12: 100%
• Category 10A: 6.00%
• Category 10B: 1.50%

This means:

• for candles and wax melts (Category 12) you must not go above 100% (and not just because that s impossible)
• for reed diffusers (Category 10A) you must not go above 6%
• for room sprays (Category 10B) you must not go above 1.5%

This is a maximum, not a target. You can use less if your performance is good. You just cannot safely use more than the limit stated.

But category 12 says “not restricted”?

Sometimes you will see “not restricted” in a category instead of a percentage.

That does not mean you can pour in as much as you like. It means that based on IFRA’s assessment there is no limit set for that particular type of product beyond other regulations and practical use.

You still need to consider:

• CLP classification at higher levels
• sooting and burn issues in candles
• base compatibility
• customer experience

In simple terms, “not restricted” just means IFRA did not place a specific percentage cap in that category. Common sense and CLP still exist.

How IFRA links with CLP

IFRA and CLP are related but they are not the same thing.

• IFRA looks at safe usage levels for fragrance materials in different product types.
• CLP looks at how hazardous a mixture is and what needs to appear on the label.

Your IFRA limit might be 10% for a candle. That tells you the ceiling for safe use. CLP then tells you how that 10% affects your label for that particular finished product, for example whether it triggers Warning, Danger, pictograms, allergens and so on.

You need both. IFRA to decide how much to use. CLP to decide how to label the final product.

What changed with IFRA 51

IFRA 51 is one of the more recent updates to the IFRA standards. It brought in new limits and changes for certain fragrance ingredients.

For you as a maker, the key points are:

• your supplier may now issue IFRA 51 certificates instead of older versions
• some maximum percentages might have gone down
• some fragrances that were fine in higher loads may now be restricted

This is why using current IFRA certificates matters. Old paperwork can give you usage levels that are no longer considered safe.

A simple worked example

Imagine you have an IFRA certificate for a fragrance called “Winter Spice”. On the certificate, the table shows:

• Category 12 (candles, wax melts): 8.00%
• Category 10A (reed diffusers): 5.00%
• Category 10B (room sprays): 1.50%

Here is how to use that information:

• You make a wax melt. You know your safe upper limit is 8%. You could choose 6%, 7% or 8%, but not 10%.
• You make a reed diffuser. Your upper limit is 5%. You might use 4% or 5% in your base, but not 7% just because “it smells stronger”.
• You make a room spray. Your limit is 1.5%. Using 5% because you saw it in a recipe online would not be safe.

Same fragrance, different usage limits for different product types. That is the whole point of IFRA categories.

Common red flags when using IFRA certificates

Here are some very common mistakes makers make with IFRA:

• using the candle category for everything to keep it “simple”
• ignoring the category description and guessing
• using an IFRA certificate for an old version of the oil
• using screenshots from Facebook or Pinterest instead of real paperwork
• confusing fragrance load with fragrance content
• assuming every oil from the same supplier has the same maximum percentage

If you are not sure, ask the supplier for clarification before you build your formula around a guess. It is much easier to check than to redo a full product line.

Why IFRA alone does not make your product safe

This bit is important. IFRA limits are only one part of the puzzle. They tell you how much fragrance you can safely use. They do not automatically make the finished product legal or compliant on their own.

For example, you might have an IFRA limit that says your reed diffuser (Category 10A) can safely use a certain percentage of fragrance in a particular solvent. On paper that looks fine.

However, once you mix the fragrance with the solvent, the final mixture might:

• trigger the need for child resistant fastenings
• trigger tactile warnings on the container
• have physical hazards that CLP picks up

Reed diffusers are open top vessels. You cannot fit a child resistant cap to an open bottle that has reeds sticking out of it. So even if the IFRA limit says the fragrance level is acceptable for that product type, the overall mixture might still not be suitable to sell as a reed diffuser because other regulations step in.

In short:

• IFRA tells you how much fragrance you can use from a toxicology point of view.
• CLP and packaging rules tell you whether the product is safe to supply in that specific format.

You need to consider both. IFRA compliance does not magically override the rest of the law.

Before you close this tab.

You do not need to be a chemist to read an IFRA certificate. You just need to know where to look and what it is actually telling you.

Remember:

• find the correct IFRA category for your product
• read the maximum percentage in that category
• treat it as a ceiling, not a target
• use CLP to work out your finished product label
• do not rely on IFRA alone to decide if a product is safe or legal
• Common sense… underrated 

If you are ever unsure, get a fresh IFRA certificate from your supplier and ask questions before you scale up. Fixing it at the paperwork stage is always easier than fixing it once the products are out in the world.