ECJ EUROPEAN Cleaning Journal

How far does the type of carpet in an office, hotel, restaurant or other facility impact on the method used to clean it? We ask manufacturers what dictates the cleaning regime: the type of carpet, the type of soiling - or a mixture of both.

There was a time when most carpets were made from wool – a natural material that was hard-wearing, easy to dye and easy to source. However wool was also relatively expensive which meant carpet manufacturers were motivated to start looking around for alternatives.

These became widely available in the 20th century in the shape of synthetic fibres such as nylon, polyester and polypropylene. Nylon was durable and hard-wearing while polyester was hydrophobic, which made it inherently resistant to staining. And polypropylene was a good all-round material and cheaper to source than most other alternatives.

But over recent years the carpet industry has snowballed and new materials have started coming on stream at a rapidly-increasing rate. These days it is not uncommon to come across carpets made from bamboo, viscose, natural sea grass, coir, coconut or sisal for example.

Having such a wide choice of materials has led to the market becoming buoyant and dynamic. But it has also caused headaches for the carpet care companies because each material reacts differently to cleaning. For example, some vegetable materials shrink when wet while others discolour. Wool tends to hold on to water-based stains but release oil effectively. Meanwhile, polypropylene releases water easily but retains oil-based stains - and nylon holds on to both.

It is therefore apparent the type of carpet should be borne in mind when coming up with a cleaning plan. But is the type of carpet a more important consideration than the type of soiling in question?
Both factors should be considered equally according to Prochem Europe sales manager Phil Jones.

“Different cleaning methods have been developed to remove different types and amounts of soiling,” he said. “For this reason, some carpet and carpet tile manufacturers specify a certain cleaning regime to maintain their product.”

Fibre sensitivity
For example, manufacturers may discourage spray extraction cleaning but recommend using a dry compound instead, he said. “In some cases this may be to protect the carpet backing material, or it may be due to the sensitivity of certain fibres such as jute or sisal,” he said. “However most carpet fibres can usually be wet-cleaned.”

He says the type of carpet in question has a decided impact on the cleaning method. “Cleaning a shagpile carpet would bring certain changes to the methodology, for example, whereas an extraction detergent would be beneficial when cleaning a cotton carpet,” he says. He suggests the use of Prochem B109 Fibre and Fabric Rinse as an extraction detergent in this instance. “This has the potential to help prevent any cellulosic browning from potentially being released and leaching on to the surface,” he said.

The easiest and safest maintenance method for cleaning wool or synthetic carpets is encapsulation, according to Jones. “Deep pile carpets will hold more soil and may require full hot water extraction cleaning,” he adds.

Different cleaning methods are designed to remove different amounts of soiling depending on whether the carpet requires a maintenance clean, a deep clean or a restoration clean, he said. “For instance, If the carpet or carpet tile has a loop pile then bonnet skimming or brushing may not be the most suitable method, since the friction caused by a rotary method may cause abrasion to the loop-pile carpet,” he said.

The type of environment in which the carpet has been laid can also make a difference to the cleaning methodology, he says. “For example, a wool carpet that has been laid outside the kitchen area of a popular restaurant would have hundreds of visitors walking over it and potentially dropping greasy food on to the carpet,” he said. “As a result it may become black and thick with grease which will be trampled in by the constant traffic. This type of carpet would then need special attention by a technician.”

He says a strong, alkaline pre-treatment such as Prochem’s S789 Power Burst would effectively tackle large amounts of deeply-ingrained grease. Once this grease has been released from the fibres the carpet should then be treated with an acidic rinse detergent such as Prochem B109 Fibre and Fabric Rinse, he said.

“The same wool carpet in a domestic environment would not have the same footfall as the commercial area so would not have the same levels of soiling,” he said. Here he would recommend a less alkaline, softer pre-treatment such as B107 Prespray Gold before rinse-extracting with Prochem B109 as before.

Many methods

According to Jones, carpets may be cleaned and maintained using a wide variety of methods. “Options range from very low moisture systems to hot water extraction methods,” he said. “But the actual amount of moisture used by the operator needs to be carefully thought through: there needs to be enough to release the soiling contained within the carpet but not so much as to cause the carpet to shrink, ripple or initiate cellulosic browning.”

He believes the safest - and potentially the quickest - method of carpet cleaning in an environment such as a commercial office is to bonnet skim the area. “However, this will only remove the surface soiling and leave deeper soiling in place,” he said. “This method therefore needs to be built into a full maintenance programme that also includes periodic hot water extraction cleaning to allow water and detergents to go deep and clean further down.”

Companies like Prochem work closely with carpet manufacturers to advise on available cleaning techniques, says Jones. “We will also train our customers on how best to maintain their choice of floor covering – something that often represents a high investment,” he said.

Legend Brands Europe executive general manager Paul Brown says there is usually no need to change the cleaning method according to the type of carpet in question. “It is only the cleaning solutions that need to be different,” he said.

Identify the carpet

The type of soiling will determine the solutions used along with the type of carpet, he adds. “Both factors should be given equal consideration,” he said. “I would recommend hot water extraction for cleaning all types of carpet, and the only time you would use a different cleaning method would be for a light maintenance clean or if the carpet is not wet-cleanable.”

However he adds it is important to identify the type of carpet prior to cleaning. “For example, for a wool carpet you would use wool-safe products,” he said.

According to Brown, vacuuming should be part of the process in all cases. “Prespray solutions should be used when cleaning heavy traffic areas, followed by a hot water solution extraction via portable extractor or truckmount,” he said.

He says delicate cleaning is required on some new types of carpets such as sea grass, rayon, viscose and silk. Legend Brands Europe offers a range of carpet cleaning solutions and spot removal products under the Chemspec brand.

It is not only the newer types of carpet material that cause problems for manufacturers, says Diversey’s global Taski portfolio manager Lawrence Osborne.

“Expensive wool and wool-mix carpets are well known to shrink or even bleed colour if too much water or chemical is used,” he said. He suggests using encapsulation - a comparatively new application designed for intermediate cleaning - to help protect against this problem.

“Encapsulation generates millions of bubbles to avoid over-wetting,” he said. “It has a very short drying time and the application may be used for cleaning the top and middle levels of the carpet fibre as frequently as once a week.” Diversey’s Taski Procarpet 30 and 45 offer two applications in one machine including carpet encapsulation.

The chosen carpet cleaning method should always be based on the structure, density, material and backing material of the carpet along with the type of floor and adhesive used, according to Kärcher trainer Alexander Kendel.

Wool special case

“Depending on the type of dirt in question the operator may choose to carry out a maintenance, intermediate or deep clean,” he said. “In some cases - such as with press boards, jute backing and water-based adhesives - only damp intermediate cleaning may be carried out so as not soak the carpet.”

He recommends the use of an upright brush-type vacuum cleaner or carpet sweeper for maintenance cleaning and the iCapsol with a microfibre pad for intermediate cleaning.

Wool is a special case because wool carpets are bonded with animal fats, he said. “These serve as a protective layer and should not be removed,” says Kendel. “Excessive machining of wool carpets can cause the fibres to felt, while strongly alkaline carpet cleaners can destroy the fibres. And only cleaning agents with the Woolsafe certificate are suitable for cleaning wool carpets.”

Plant-based fibres such as cotton, jute, sisal, flax and hemp are sensitive to acids below pH 3 and resistant to alkalis above pH 10, he says. “They are also resistant to organic solvents as well as being temperature-sensitive,” he said. “And almost all synthetic fibres besides polyamides are resistant to acids below pH3.”

According to Kendel, carpeted floors are becoming in greater demand today due to an increased range of patterns, designs and structures on the market. “With proper cleaning carpets are also suitable for allergy-sufferers as they hold the dust well compared with hard floor coverings where the dust is raised with the slightest of breezes,” he said.

But he adds it is always crucial to consider the cleaning and care instructions before tackling a carpet cleaning task. “A precise knowledge of the properties of the carpet and its cleanability are essential,” he said.