Dilution Ratios Explained — Module 3

Free Taster Micro-Course. This module gives you a practical introduction to dilution ratios for cleaners. For full professional training with CPD certification, explore our paid courses.

What you'll learn in this module

  • The risks of over-dilution and under-dilution
  • The most common dilution mistakes cleaners make
  • How to get dilution right every time on the job

The Risks of Getting It Wrong

Both over-diluting and under-diluting a chemical cause problems — just different ones.

  • Under-dilution (too much chemical): Increases cost, can damage surfaces, leaves chemical residue, and poses a COSHH risk to you and building occupants. Strong concentrations of some chemicals can bleach fabrics, corrode metals, and irritate skin and airways.
  • Over-dilution (too much water): The product may not work at all. Bacteria may survive. Soiling may not be removed. You end up using more product and more time to get the same result — costing you money.
Key point: The manufacturer's stated ratio is the sweet spot — effective, safe, and cost-efficient. Deviating in either direction costs you.

Common Dilution Mistakes

Mistake Why It Matters
Guessing the amount of chemical Even experienced cleaners misjudge volumes without measuring. Use a measure every time.
Adding water to chemical Always add chemical to water. Reversing this can cause splashing of concentrated product.
Using the same dilution for every task Different tasks require different ratios. A sanitiser for food surfaces has a different ratio to a carpet pre-spray.
Not checking the label or SDS Ratios vary between products even from the same manufacturer. Always check.
Topping up a part-used bottle without emptying it first You lose track of the concentration. Empty, rinse, and mix fresh each time.

Getting It Right Every Time

Use a measuring jug or dosing cap — never free-pour. Keep the reference table from Module 2 in your kit bag or on your cleaning trolley. If you are unsure of the ratio for a product, check the label or SDS before mixing. When in doubt, contact the manufacturer or supplier.

✅ You have completed Micro-Course 6: Dilution Ratios Explained

Well done — you now know how to read, calculate, and apply dilution ratios correctly and safely.
Disclaimer: This micro-course provides a general introduction to dilution ratios for cleaning chemicals. It is not a substitute for full professional training. Always follow manufacturer guidance and refer to current HSE guidance for your specific workplace.