Nilfisk offers a brief insight into the basics of stain removal

In principle, stains should be dealt with as soon as possible. As more than 90 per cent of all stains consist of residues from sugary drinks, attempts should first be made to remove those with clear, lukewarm water.

Sugary drink stains can be dealt with in this way: Work the stained area with a wet cloth, sponge or brush. Avoid rubbing on delicate surfaces with a pile. If the stain is not removed, use normal stain removal agents. Dirt, which resists removal, should first be carefully loosened using suitable equipment (back of a knife, spatula or spoon) without damaging the pile, and the loose substances should be vacuumed up.

Before using carpet cleaning agents or specialist dry cleaning materials, carpets should be tested in an inconspicuous spot or on an off-cut for colour-fastness. Dirt containing oil or fat can be removed using suitable carpet cleaning agents or stain removers. For marks covering a large surface area, intermediate cleaning methods can be used.

Use of washing-up liquid or gentle detergents, etc. is not recommended as these raise the risk of repeat staining of the covering due to residues. Soil like tar, asphalt, felt-pen ink, glue or paint can only be removed using organic solvents. When using these, health and environmental protection directives must be followed. If possible, products with a water-soluble solvent (e.g., those based on diethylene glycol ethers), which are not considered hazardous, should be used.

Dissolved stain substances and, when relevant, stain removal agents must not remain in the textile floor covering to avoid the same stain recurring or unnecessary repeat staining. Attention must always be paid in such cases to rinsing thoroughly with water and then draining (wet vacuuming, extraction).

Specific stain treatment

Chewing gum liquid agents, generally based on citrus-turpentine, are very well-suited to simple removal of chewing gum. Freezing sprays used to be offered as chewing gum removers, but these contained ozone layer-destroying chlorofluorocarbons (CFCs) and were, therefore, taken off the market. Rust is removed with 10 per cent oxalic acid solution (available from chemists as ‘salts of lemon’). After treatment, the covering must be thoroughly treated with clear water. Blood and urine stains are removed using products containing enzymes, which work overnight.

A ‘rust stain’ often remains in blood stains due to its haemoglobin (iron content); this can be removed with 10 per cent oxalic acid. Acid stains are removed with varnish paste-based solvent, but caution needs to be taken with coverings sensitive to alkali. Moulds are removed with 6 per cent hydrogen peroxide solution. Soak a cloth in the liquid. Let it work overnight. Attention needs to be paid to bleaching effect and fading of dyes. Ink is removed with sodium dithionate solution and fruit stains with enzymes, oxidation or reducing agent, but in both cases, better to test first in an unobtrusive spot.

Candle wax stains are removed using a hairdryer. Place a coffee filter paper on the stain and warm the spot carefully. Remove any residue with solvent. Another method is to flood the stain with hot water and treat the spot immediately with a wet vacuum.

Shading is the term for stains that arise without the effect of dirt substances. While these look like seriously stained marks (similar to a large drink spill), their cause is due to the pile of the textile covering being irregularly displaced. The phenomenon occurs in all kinds of fabrics. The effect can also extend over several storeys, with the affected areas lying precisely one above another. Shading cannot be removed by cleaning.

Burn marks cannot be removed by cleaning. The affected part of the textile covering must be replaced.