Code Purple! Pressure is on to boost cleaning safety

Published:  18 October, 2022

The Water Jetting Association is about to launch a new code of practice for pressure washing. WJA president John Jones explains why it’s urgently needed.

Pressure washing has become so commonplace that many businesses are not taking nearly enough precautions to protect their operatives or colleagues in the work area. Technology has advanced rapidly, not least because pressure washing is such a useful process: it is used at thousands of industrial sites across the UK every day to clean and degrease machinery, clean floors and decontaminate production vessels.

The Water Jetting Association (WJA) is now launching a new pressure washing code of practice to help ensure operational and safety measures are aligned with these advances in capability. The need is urgent. Many operatives do not receive structured training, do not use the right PPE, and are unaware of the hazards they face. Injuries that can be caused during pressure washing have some specific characteristics that can make them particularly dangerous.

4th degree burns

Here is a real example. An experienced pressure washing operative was using a steam pressure washer to clear a frozen drain. As he pulled the hose from the pipe, he lost control of it and the water jet cut through his boot, filling it with 1100C water at 207 bar (3,000 psi), travelling at 440 miles per hour.

The incident lasted less than three seconds. But the operative suffered 4th degree burns. After emergency surgery, he needed many further surgical operations as continued efforts were made to rebuild his foot.

It is just one of many pressure washing injuries. In another, a dockyard operative slipped due to the unexpected power of a water jet, allowing the nozzle to swipe across his supervisor, lacerating his upper thigh. Again, urgent and extensive hospital treatment was needed. The easy access to pressure washing equipment can lull people into a false sense of security. Those who operate home pressure washers in shorts and flipflops are likely to take that mindset into the workplace.

Colour purple for safety

The Water Jetting Association (WJA)’s new pressure washing code of practice is designed to challenge this. It lays out the steps needed to optimise the safe use of low-pressure water jetting equipment.

It also explains why these steps are important and what needs to be done if something does go wrong. The WJA, founded in 1980, is the UK’s trade body for the water jetting industry. We follow international NACE standards that divide water jetting into four bands of increasing pressure. Pressure washing is covered by the lowest band – Low Pressure Cleaning, with water pressures up to 207 bar or 3,000 psi. The WJA already has two codes of practice – the Blue Code for high pressure and ultra-high pressure water jetting, and the Red Code for water jetting used for drain and sewer cleaning.

The new pressure washing code – it will be the Purple Code – will support safe and productive water jetting in the at lowest of the NACE pressure bands. It introduces a new operational standard and health and safety framework for companies that carry out pressure washing, and those who rely on its advantages. Tasks include cleaning plant, machinery, and vehicles, mud from roads during highway repairs and construction, and many other jobs that would be too arduous and costly with other cleaning systems.

In all cases, without a clear operational framework a code of practice provides, there is opportunity for field teams to improvise and develop unsafe and suboptimal practices.

Water jetting injuries

Safety is at the heart of the pressure washing code of practice, which directly addressed the unique risks associated with water jetting.

There are three main ways water jetting systems cause serious injury or death: being struck by an uncontrolled hose or jetting nozzle; suffering a laceration that causes a massive bleed; or a fluid injection injury, caused by the water jet puncturing the skin and entering underlying tissue.

What is commonly not understood is that a fluid injection injury can be caused by a water jet with a pressure as low as 100 psi (7 bar). Consider, then, that shop-bought pressure washers can reach pressures of 2,500 psi (170bar). There are two other big problems with fluid injection injuries. Firstly, it is not just water that can get into the body. The water jet can carry other particles and fluids with it, including dirt, bacteria, viruses, parasites, chemicals, oils and grease.

The jet can be so powerful, it can enter a forearm, for example, strike the bone and then be diverted up to the shoulder, causing catastrophic tissue damage and taking these pollutants with it.

Secondly, the injection point can be so small, that the injured person, their colleagues, and then medical personnel often do not realise the seriousness of the injury. This can result in an injured person not receiving the urgent and extensive treatment they need, causing long-term problems such as secondary infections. In the worst cases, this can result in the need for amputations or fatalities.

The WJA’s pressure washing code of practice addresses these risks and details the appropriate steps needed to mitigate them.

Best medical advice

For example, it includes our new water jetting medical guidelines. They were created following research into water jetting injuries commissioned by the WJA and carried out by a team of leading NHS trauma doctors. Their study, published in European Journal of Trauma and Emergency Medicine, confirmed the likelihood that many high-risk fluid injection injuries are not being properly diagnosed by GPs and emergency doctors.

The guidelines are in the form of an algorithm, giving clear stepby-step information about how to respond to water jetting injuries from the moment they occur through to post-emergency treatment therapies. Every person, from the first responder, to the paramedic, the emergency doctor, GP and therapist, has a part to play in minimising long-term effects. With this in mind, all WJA-qualified water jetting operatives carry a medical card alerting emergency medics to consider fluid injection injuries.

Skills training

The new pressure washing code of practice has sections covering training and competency, site and equipment set-up, and the different types of pressure washing pumps and equipment. This includes hot water systems which, as we have seen, introduce additional risks. Also covered is equipment operation, use of PPE, and managing the pressure washing team. There is also detailed advice on risk assessment and a pre-start checklist.

A key element is effective training. The WJA is the UK’s main provider of water jetting training. This includes a City & Guilds pressure washing course delivered by WJA-approved training providers and instructors. Lasting at least five hours, it is designed to teach class-based and practical skills for safe and productive pressure washing.

Professional approach

The WJA is keen to promote this professional and knowledgebased approach to pressure washing. We welcome pressure washing contractors and organisations that carry out pressure washing as WJA members. We also value the lead they take in promoting safety in their industry.

They include TPC Brickwork Cleaning, in Hampshire. Company owner Kris Jasinksi commented: “We’re a member of the WJA because we want to protect our operatives and everyone around us when we’re pressure washing.

“Undertaking the WJA pressure washing training has made a big difference. I can see our safety has gone up a level. The advice the WJA gives is central to how we go about our work and to our business success. I have no doubt about that.”

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