ECJ EUROPEAN Cleaning Journal

What are the sustainability arguments for using high-pressure washers – which often remove the need for using chemicals, but use copious amounts of water in their place - compared with other cleaning methods, asks Ann Laffeaty?

Sustainability needs to be built into every cleaning process in today’s environmentally-conscious society. Companies are continuously weighing up the pros and cons of using one cleaning method compared with another in terms of the impact it is likely to have on the planet and eco-systems.

But it can be difficult to make a clear sustainability assessment when there are so many factors to be considered. A manual cleaning method may require no external power source but might only be effective when used with strong chemicals, for example. It could also prove to be less efficient when compared with machine cleaning. And manual cleaning could result in aches and pains for the operative – a factor that will have a negative impact on its overall sustainability.

The picture is similarly complex as far as high-pressure cleaning is concerned. This method uses concentrated water jets to blast off dirt from surfaces such as walls, floors and facades. Depending on the water pressure used and the surface in question, cleaning can often take place using cold water alone and without the need for chemicals.

However, high-pressure cleaning requires the use of significant quantities of water which is becoming a precious resource in many countries. And there are certain risks associated with this method such as the possibility of skin tearing, eye injuries or kickback due to the force of the water supply.

So once these factors have been taken into account, can high-pressure cleaning be described as an environmentally-friendly way of tackling a task?

Using a high-pressure cleaner is inherently more sustainable than working with a standard water hose, according to Kärcher’s senior product management director for professional high-pressure cleaners Volker Steigauf. “This is because it reduces water consumption by up to 80 per cent,” he said.

“When high-pressure cleaners are used with the right type of power source and with suitable accessories there is already a good balance achieved between resource consumption and cleaning
quality. However, there are other factors that can further improve this relationship and ensure an even greater level of sustainability.”

He says the choice of accessories and the level of power used can both have a significant impact on the sustainability and performance of cleaning, particularly when the machine is used with warm water.

“The nozzle and the pressure used should be selected to match the unit performance,” he said. “A nozzle that is too small will limit the machine’s performance while a nozzle that is too large will lead to the water coming out with too little pressure.” Point jet nozzles are suitable for tackling localised, stubborn dirt while surface cleaners are often the tools of choice for large areas, says Steigauf.

One of the main sustainability arguments for using a high-pressure cleaner is the enhanced efficiency of its cleaning performance, he said. “Users will benefit from significant time, water and energy savings while the use of cleaning agents can also be reduced,” explained Steigauf.

Even cold water high-pressure cleaners can be used to remove stubborn and greasy dirt, he says. “This makes them much more efficient than cleaning with a normal water hose, for example,” said Steigauf. “The hot water high-pressure cleaner in comparison has the advantage that the water will dissolve greasy dirt more quickly and will have a powerful effect against germs even without cleaning agents. And in addition, surfaces cleaned with hot water will dry much more quickly. So the bottom line is: hot water high-pressure cleaners save a great deal of time and money.”

He claims that an operator using a hot water high-pressure cleaner can make time savings of around 40 per cent when compared to cleaning with cold water. Available for hot water high-pressure cleaners is Kärcher’s eco!efficiency mode which is said to allow the operator to clean more surfaces with the same amount of water. The mode also regulates the water temperature of the high-pressure cleaner to 60 degrees C.

More efficient

The company’s machines can be used with an eco!Booster nozzle which is said to allow water to be employed more efficiently. “Compared with a standard flat jet nozzle it can help to increase the area performance along with the efficiency of the water and energy used by 50 per cent,” he said. “And in addition to the conservation of resources, working time is also significantly reduced.” The eco!Booster nozzle from Kärcher can be teamed with cold and hot water high-pressure cleaners up to 300 bar and 80 degrees C.

All Kärcher’s hot water high-pressure cleaners can be operated with biodiesel and e-fuels in accordance with DIN EN 15940, says Steigauf. “These are made from renewable raw materials and are CO?- neutral,” he said. “Thanks to better combustion properties compared with traditional diesel, the emissions are considerably reduced which helps to support the protection of the environment in the long term.”

Addressing the potential risks of using a high-pressure cleaner, Steigauf says that concern for the user’s health and safety has become a driving factor in the industry. “There is an increasing focus on ergonomics,” says Steigauf. Kärcher’s machines feature an automatic hose reel and the EASY!Force trigger gun, which is said to reduce the holding force required by the operator’s hand and fingers.

High-pressure cleaning can certainly be a sustainable cleaning method when good protocols are applied and where the user has a strong awareness of the environmental impact, says IPC delegate for product compliance and regulatory affairs Mario Scarpa.

“High-pressure cleaning is a particularly effective method of removing tough dirt and grime,” he said. “However, in order to enhance its long-term efficiency it is important to use modern equipment where the technologies are designed to regulate resource usage.

“Machines with advanced controls will allow operators to manage water, energy and cleaning agents more efficiently.”

Where conditions permit, using osmotic deionised water instead of chemical agents can make high-pressure cleaning a more sustainable choice, says Scarpa. “This is particularly relevant for applications such as maintaining photovoltaic panels or cleaning large glass surfaces, where the absence of chemicals may help to protect surrounding ecosystems,” he said.

Water essential

Water is an essential component of any wet cleaning method – with high-pressure cleaning being no exception, says Scarpa. “However, what truly matters is the efficiency with which the water is used,” he adds. “Selecting the appropriate equipment and the right techniques for the specific cleaning task can significantly reduce water consumption, and this in turn makes the method more environmentally responsible.”

IPC PW-H61 and IPC PW-H101 machines are said to offer advanced controls that allow operators to manage water, energy and cleaning agents more efficiently. Other sustainable features of the models include the Ecosystem, which cuts diesel consumption and emissions by automatically setting the water temperature to 60 degrees C; the Advanced Multifunction Safety Control for enhanced machine safety and operator protection, and the Digital Temperature Stabilizer Control for precise water temperature control.

Scarpa concludes he believes high-pressure washers in general offer a sustainable cleaning solution. “The key lies in how the method is executed, ensuring the equipment used is appropriate and that resources are optimally managed for the task at hand,” he said.