Room Spray Guide: Ratios, Bases, and Fragrance Oils

1. What a room spray actually is (and what it is not)

In formal terms, a room spray is a non-skin fragrance product designed to be sprayed into the air or onto selected textiles and surfaces. Regulatory frameworks usually place room sprays in IFRA Category 9 (air fresheners and some fabric sprays), which determines the maximum allowable fragrance percentage for each specific fragrance.

A basic room spray has four functional components:

1. Fragrance phase

• Fragrance oils, essential oils, or blends.
  

2. Carrier/base

• Alcohol (ethanol/perfumer’s alcohol),
• Solvent base (e.g. Augeo® Clean Multi or commercial “room spray base”),
• Water (with solubiliser).

3. Solubiliser/emulsifier (if needed)

• Commonly Polysorbate-20 or similar.

4. Optional functional extras

• Preservative (if water is present),
• pH adjuster,
• Humectant or other actives (for linen/pillow mists).

 

2. Choosing your overall formulation strategy

There are three main strategies that serious makers use:

1. Alcohol-based sprays (classic fine mist, fast evaporation)

• Carrier: high-proof ethanol or commercial alcohol room-spray base.
• Pros: clear solutions, quick-drying, strong initial impact, low residue.
• Cons: flammable, more regulatory constraints for transport and storage.

 

2. Solvent-base sprays (e.g. eco-solvent like Augeo Clean Multi)

• Carrier: specialty solvents optimised for home fragrance.
• Pros: clear, non-flammable (for some bases), very good solubility, strong scent, longer linger.
• Cons: can feel “oilier” on some surfaces, not always suitable for skin.

 

3. Water-based sprays with solubiliser (often for linens & fabric)

• Carrier: demineralised water + solubiliser (e.g. Polysorbate-20) + a small alcohol fraction.
• Pros: less flammable, softer profile for textiles, easier perception as “natural”.
• Cons: needs preservative, can be hazy/milky, may leave a slight residue if overused.

 

When you design a formula, decide first:

• Target: air only, air + textiles, or multi-surface.
• Brand position: eco/solvent-free, alcohol-style fine fragrance, or high-impact industrial.
• Legal constraints: IFRA limits, CLP/GHS labeling (EU/UK), VOC regulations (e.g. CARB in the US).

3. Fragrance load: how much fragrance oil should you use?

3.1 Typical ranges

Most professional suppliers suggest 3–10% fragrance oil in room sprays:

• 3–5% for subtle mists, delicate or strong oils.
• 5–8% for general room sprays.
• 8–10% for stronger impact, provided the IFRA limit for that fragrance allows it.

For certain solvent bases like Augeo® Clean Multi, some diffuser formulas use up to 15–25% fragrance, mainly for reed diffusers.
For room sprays, you usually don’t need to go that high; 3–10% is normally plenty.

3.2 Always check IFRA limits

Each fragrance oil comes with an IFRA certificate listing the maximum allowed percentage for each category (Category 9 = air fresheners, some fabric sprays). Professional guides strongly recommend respecting these limits when choosing your load.

If your target is 8% but IFRA Category 9 max is 3%, you must stay at or below 3%.

 

4. Bases: ethanol, solvent bases, and water systems

4.1 Alcohol bases (ethanol / perfumer’s alcohol)

Several pro recipes for room/linen sprays use a small % of alcohol + water + solubiliser, but in a pure alcohol system you can keep it very simple: alcohol + fragrance.

Why use it:

• Very fast evaporation → crisp, non-sticky finish.
• Generally clear if your fragrance is compatible.
• Classic perfume-like experience.

Watchpoints:

• Flammability → impacts shipping and labeling.
• Some customers dislike the ethanol odour on spray (usually flashes off in seconds).

Practical starter formula (100 g / 100 ml batches)

Target: Air room spray (no direct fabric use on delicate textiles).

Formula (100 g):

• 5% fragrance oil (5 g)
• 95% perfumer’s alcohol (95 g)

Steps:

1. Weigh fragrance oil into a beaker.
2. Add perfumer’s alcohol, stir until fully clear.
3. Let rest 24–48 h (or more) to allow micro-bubbles to escape and the scent to “marry”.
4. Filter if needed, then bottle in fine-mist atomisers.

Watchpoints:

1. For stronger scent, go up to 8–10% fragrance if allowed by IFRA Category 9 and flashpoint considerations. 
2. For a softer linen spray, reduce to 3–4%, and test on fabrics.

 

4.2 Eco-solvent bases (Augeo® and commercial room spray bases)

Augeo Clean Multi is a bio-based solvent widely used in reed diffusers and room/linen sprays. It has:

• Very good solubilising power for fragrance oils.
• Low odour profile.
• Non-flammable classification in many markets.
• VOC-compliant status in several jurisdictions (e.g. CARB-compatible scent loading).

For room sprays, 3–10% fragrance in an Augeo-type base is usually sufficient. Many “eco room spray bases” from candle suppliers are built on similar logic: bio solvent + modifiers, designed for 3–10% fragrance.

Why use it:

• Excellent clarity and stability with fragrance.
• Often non-hazardous or low-hazard, sometimes not requiring CLP label at low loads.
• Good long-lasting scent and slow, even evaporation.

Watchpoints:

• Feels slightly less “dry” than pure alcohol on textiles.
• Still requires CLP/IFRA assessment at higher fragrance loads.

 

Practical starter formula (100 g / 100 ml batches)

Target: Room & light textile spray with non-flammable base.

Formula (100 g):

• 7% fragrance oil (7 g)
• 93% eco room-spray base or Augeo Clean Multi (93 g)

Steps:

1. Weigh fragrance oil.
2. Add to the eco base (Augeo or similar), stir slowly until the blend goes homogeneous and clear.
3. Rest 24–72 h to check for separation or haziness.
4. Bottle in trigger sprays or fine misters.

Watchpoints:

• You can scale fragrance between 3-10%; for home fragrance, higher loads (15–20%) are typical for diffusers, not necessary for sprays.
• Always re-check CLP classification when you change the percentage.

 

4.3 Water-based systems with solubiliser

Water-based sprays combine:

• Water (usually demineralised or distilled).
• Fragrance oil.
• Solubiliser/emulsifier (often Polysorbate-20).
• Optional preservative (e.g. sodium benzoate) when water is present.

Pros: Lower alcohol content.
Softer, textile-friendly positioning (depending on fragrance).

Watchpoints: Some perfumers note that large water fractions increase solubility problems; many fragrance ingredients are not water-soluble, and solubiliser residues can feelsticky or slipperyon surfaces and floors.
Always test on fabrics to avoid staining or residue.

 

Practical starter formula (100 g / 100 ml batches)

Target: Linen & room mist with reduced alcohol. Many suppliers recommend 1:2:4 Preservative: Polysorbate-20: Fragrance oil by weight to obtain a clear or nearly clear solution.

First, you need to decide what percentage of fragrance oil you want to add — usually between 3–10%. Then, determine the total weight of your system, which is usually equal to the volume of your bottle.

• Polysorbate-20 = FO,g x 0.5
• Preservative = FO,g x 0.5
• Water = 100 - (FO,g + Polysorbate-20,g + Preservative,g)

Formula (100 g):

• 4g fragrance oil (4%)
• 2g Polysorbate-20 (2%)
• 1g preservative (1%)
• 93g distilled water (93%)

Steps:

1. Mix fragrance oil and Polysorbate-20; stir until the blend becomes uniform and as clear as possible.
2. Add preservative according to supplier instructions.
3. Add water slowly while stirring.

Watchpoints:

• Expect a slightly milky appearance; this is normal for many Polysorbate systems and is often hidden by opaque or frosted bottles.

• Always perform stability tests and a fabric test. (The test should be performed on white fabric)

5. Working with fragrance oils: compatibility, strength, and safety

5.1 Checking IFRA and usage rates

For each fragrance:

1. Get the IFRA certificate from your supplier.
2. Find the limit for Category 9 (room sprays, air fresheners).
3. Make sure your chosen % is at or below that limit.

5.2 Solubility and clarity

• Some fragrance oils contain highly polar ingredients and emulsifiers → easier to solubilise.
• Others are rich in heavy base notes (e.g. resins, ouds, patchouli) → harder to solubilise, more likely to haze.

If you see cloudiness / separation:

In alcohol:

• Reduce water content (if any),
• Increase alcohol strength,
• Slightly reduce fragrance load.

In water + Polysorbate:

• Increase Polysorbate,
• Reduce fragrance load,
• Try a different solubiliser or fragrance.

In eco-solvent bases:

• Check supplier’s recommended maximum load,
• Try a different eco-base or fragrance family. 

 

6. Process and testing: getting reliable results

6.1 Mixing order and technique

Phase A: fragrance + solubiliser (if used)

• Mix until clear and uniform.

Phase B: solvent/base

• Add slowly while stirring gently to avoid excessive foaming.

Phase C: water (if applicable)

• Add in several portions, mixing thoroughly.

Phase D: additives/preservative

• Add at the end, according to supplier guidelines.

What else is important? Slow mixing, resting time and small pilot batches before scaling up. 

6.2 Stability checks

Before you consider a formula “final”, run basic tests:

• 24–72 h clarity check at room temperature.
• Freeze–thaw test:
  24 h in the fridge/freezer, then back to room temperature. Observe for separation, sediment, or permanent haziness.
• Shake test: Shake vigorously, leave to stand. Persistent foam after several hours can annoy end-users.

6.3 Performance tests

Test in a realistic room size:

1–2 sprays at standard distance (30–50 cm from air or textiles).

What is important:

• Initial impact (top notes),
• Development after 5, 15, 30 minutes,
• Residual scent after 2–4 hours.

On textiles:

• Spray from a distance (30–50 cm) on white cotton swatch.

Check for:

• Staining/discoloration,
• Oily marks,
• Residue or stickiness after drying.

7. Safety, CLP/IFRA and VOC considerations

7.1 CLP/GHS and labeling (EU/UK)

For the EU/UK, if your product is classified as hazardous (e.g. due to fragrance hazards), you may need a CLP label. For example, guides for working with Augeo + fragrance (up to 25%) show how hazard classifications change with load and provide label templates. 

Some commercial room-spray bases and linen bases are formulated to be non-hazardous at typical fragrance loads, meaning they may not require a CLP label by themselves, but you must always reassess after adding fragrance. 

7.2 IFRA compliance

Room sprays typically fall under IFRA Category 9:

• The IFRA limit for each fragrance (Category 9) is the absolute ceiling for your fragrance % in the formula.
• If you sell internationally, keep IFRA-compliant documentation (Formula, IFRA certs, SDS) in your batch files.

7.3 VOC and flammability

Alcohol-based sprays are flammable and subject to transport rules (ADR, IATA). Eco-solvent bases such as Augeo Clean Multi are designed as low VOC, non-flammable options that comply with VOC regulations (e.g. CARB) while still allowing relatively high fragrance loads in air-care products.

8. Troubleshooting: common room spray problems

8.1 Cloudy or milky appearance

Possible causes:

• Insufficient solubiliser for the fragrance load.
• Incompatible fragrance components (especially resins/base notes).
• Too much water in a system with lipophilic ingredients.

Fix:

• Increase solubiliser gradually (e.g. from 4% to 5–6%).
• Reduce fragrance % slightly (e.g. from 5% to 3–4%).
• Switch to a different base (e.g. eco-solvent) or different fragrance.
  

8.2 Separation / “oil layer” on top

Possible causes:

• Fragrance not fully solubilised.
• Incorrect mixing order or insufficient mixing time.

Fix:

• Pre-mix fragrance + solubiliser thoroughly before adding water or main base.
• Allow a longer rest period and retest.
• If separation persists after 48–72 h, adjust ratios or change solubiliser/base.

8.3 Sticky floor or residue

Perfumers note that water-heavy sprays with non-volatile solubilisers can leave sticky/slippery residues on surfaces, as the solubiliser stays behind when the water evaporates. 

Fix:

• Reduce total solubiliser.
• Use more volatile carriers (ethanol or eco-solvent).
• Adjust instructions (“spray into the air, not directly onto floors”).
  

8.4 Weak scent

Possible causes:

• Fragrance % too low.
• Fragrance itself has low diffusion in air.
• Overly “heavy” base, low evaporation.
  

Fix:

• Increase fragrance load within IFRA limits (e.g. from 3% → 5% → 7%).
• Try a different base (more volatile).
• Switch to more diffusive fragrance families (citrus, aromatics, aldehydic notes).

 

9. Example development workflow for a new room spray

Define the brief

• Target: “Citrus–herbal kitchen spray, strong but not overpowering, alcohol-based.”
  

Check IFRA Category 9 limit for the chosen fragrance

• Suppose IFRA max is 8%.
  

Choose base strategy

• Perfumer’s alcohol, 5–7% fragrance test range.

Design initial trials (small batches, 50–100 g)

• Trial A: 5% fragrance, 95% alcohol.
• Trial B: 7% fragrance, 93% alcohol.

Mix, rest 48 h, evaluate

• Check clarity, no separation, no sediment.
• Do performance tests in a real room.

Adjust

• If Trial A is too weak and Trial B is perfect, you keep 7%.
• If both are harsh, drop to 4–5% and/or adjust fragrance choice (softer profile).

Document formula + batch data

• Keep record: weights, temperatures, mixing steps, observations.
  

Prepare CLP/label and IFRA documentation

• Calculate hazards for the chosen % using supplier data and any CLP calculators for your base system.