INT-HKL-2.2.1

Cleaning Chemicals and Surface Compatibility

Introduces the main cleaning chemical families (acid, alkaline, neutral, solvent, chlorine, ammonia), which surfaces each one damages, correct dilution and decanting practice, and the never-mix rules.

Your chief stew hands you a bottle of concentrate and says "1 to 100, warm water, use it on everything except the marble and the lacquer." You need to understand three things before you fill that bottle: what the chemical is, what it does to which surface, and how strong it must actually be.

The chemical families

Family Typical products Good for Destroys
Acidic (low pH) Descalers, limescale removers, toilet cleaners Limescale, hard-water spotting, urine scale Marble, limestone, onyx (etching), grout, chrome plating, natural stone sealers
Alkaline (high pH) Degreasers, all-purpose cleaners, oven cleaner Grease, oils, protein soils Aluminium, some lacquers and painted surfaces; strips stone sealers; dulls polished finishes
Neutral pH Neutral floor/stone cleaner, mild detergent Everyday soil on almost any surface Little — the safe default onboard
Solvent Alcohol, acetone, spirit-based sprays Adhesive, ink, some oils Lacquer, plastics, varnish, leather, acrylic (crazing)
Chlorine bleach Sodium hypochlorite Mould, disinfection of hard surfaces Stainless steel (pitting/corrosion), silk, wool, coloured fabrics; releases toxic gas if mixed with acid or ammonia
Ammonia-based Many glass cleaners Glass, some metals Certain lacquers, tinted/coated glass, leather, aluminium

Dilution: stronger is not better

Over-dosing costs money, leaves residue (which then attracts dirt and shows streaks), and increases chemical exposure. Under-dosing simply does not clean.

  • Read the dilution ratio on the label. 1:100 means 1 part product to 100 parts water — roughly 10 ml in a 1-litre bottle.
  • Always add water first, then the chemical — this reduces splashing and foaming.
  • Use a dosing pump, a measuring cup or a marked syringe. Never "a good glug".
  • Mixed solutions go in a correctly labelled bottle with the product name and hazard information — never in an unlabelled bottle and never in a drinks bottle.

The rules you never break

  • Never mix chemicals. Bleach + acid releases chlorine gas. Bleach + ammonia releases chloramine. Both have killed people in confined spaces.
  • Never use an acid on marble, limestone or onyx. Not once. Not diluted. Not "just to try".
  • Never use chlorine bleach on stainless steel — the chloride ion pits and rusts it.
  • Never spray directly near lacquer, silk, electronics or A/C returns. Spray the cloth.
  • Always ventilate — yacht heads and laundries are small; vapours build fast.

Choosing the product

Ask, in order: What is the surface? What is the soil (grease, limescale, dust, protein, mould)? What is the least aggressive product that will shift it? Only then reach for the bottle.

Onboard Notes

  • The safety data sheet (SDS) for every chemical onboard must be available; know where the file is.
  • If a product is not on the boat's approved list, it does not go on the boat's surfaces — including anything you bought ashore.
  • Residue is a visible failure. Rinse or dry-buff after any detergent on gloss and glass.
  • If a chemical contacts an unintended surface, flush with clean water immediately and report it.

Practice questions

5 questions
recallcore

recall · core

Match each chemical family to what it damages: acid, alkaline, chlorine bleach, ammonia, solvent.

recallcore

recall · core

What are the two chemical mixtures that must never be made, and what do they produce?

recallcore

recall · core

Describe correct decanting and dilution practice.

scenariostretch

scenario · stretch

Someone hands you an unlabelled spray bottle of a clear liquid found in the guest head and says "it works great on everything". What do you do?

oralstretch

oral · stretch

Walk through how you decide which product to use on an unfamiliar cleaning job.

Independent study. xplor is not an IAMI- or PYA-accredited GUEST training provider. This course covers the ground assessed in GUEST Unit 32; it awards no GUEST unit, certificate or Certificate of Competency and does not count toward one.

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