It's the People that Count
Each worker involved in a high pressure water job must be physically and mentally fit. Everyone has an important role to play.
If you're working in or around a high pressure water blasting area, never approach a water jet operator while the jet is operating. Wait until the jet is stopped and the operator sees you.
High pressure water blasting has the potential to be very dangerous. Always use safe work practices and procedures, wear appropriate PPE, and be alert at all times on the job.
A Powerful Force
Water-one of nature's most powerful forces, one of man's most powerful tools. From drinking water to rain, water is an integral part of life. Most people view water as harmless, yet some industrial uses of water can be highly dangerous if not used correctly.
Hand lancing is one method of high pressure water blasting, and is often used in refineries and petrochemical plants. It can be used for removing unwanted residue from surfaces or for cutting through materials like steel and concrete.
Water blasting uses extremely high pressure. The jet of water is usually in the 10,000 psi pressure rate, but can exceed 60,000 psi (car washes are about 1,200 psi). In fact, the velocity of water at nozzle tip often exceeds that of a bullet coming out of a gun.
When injuries occur with high pressure water, you can count on them to be severe. Along with the physical damage caused by the blast, your body is injected with harmful bacteria. Unless immediate medical care is initiated, serious infection will occur.
The high pressure blast can cut through skin, ligaments, and bone in one quick motion resulting in the loss of a body part. If injected into more vulnerable parts of the body like the chest, abdomen, or head areas, death may be the final result.
Other hazards with high pressure water blasting:
The combination of water and residue may create dangerous vapours
Slips and falls may occur on wet or frozen surfaces
Confined Space Hazards
Hand lancing in confined spaces should only be used when no other methods can be found. In a confined space you may face:
Limited space for lance control
Limited entry and exit points
Poor communication with fellow workers
Poor footing and uneven surfaces
Difficult rescue of workers due to the design of the confined space
Operating a high pressure water blaster requires detailed training, including safe work practices and procedures. If you have not received specific training, you are not qualified to use this equipment. You will be a danger to yourself and others.
Once you are trained, you must demonstrate that you have the knowledge and experience under the supervision of an expert operator before you do the work on your own.
Start a water blasting job by doing pre-job planning. Each different type of cleaning or cutting operation should have specific written work procedures. The crew should meet before doing the job to discuss potential hazards, environmental problems, and safety standards. All workers in the area must agree on a code of signals. Checklists are a useful tool to ensure that everything's in place and working properly.
Before You Start
Before any work starts, put up warning barriers and signs-outside the range of the jet.
Before you start the job, you need to make sure everything's working correctly and in the right place.
Hoses-Arrange hoses so they do not create a tripping hazard. Check for damage, wear, or imperfections. It's important to keep an eye on hoses throughout the job. Remember to protect hoses from being run over or crushed.
Nozzle Tips-Before installing the nozzle tip, start the pump and flush the system completely. Inspect nozzle tips for damaged or plugged jets. Nozzle tips must be completely open. (Ensure the unit is shut off and disconnected before you install the nozzles.)
Starting the System-When you start the system, increase pressure slowly and inspect for leaks or faulty components.
Personal Protective Equipment (PPE) is necessary for all high pressure water blasting jobs. Although different jobs may require additional protection, here are the basics:
Full face and eye protection shield
Waterproof clothing, fully covering body and arms
Hand protection if necessary
Foot protection-waterproof with steel toe caps (High top CSA Rated)
Hearing protection-most high pressure water systems have high noise levels
Respiratory protection-when necessary, particularly in confined spaces
PPE will not completely protect you from high pressure water impact, but may lessen the extent of an injury.
Doing the Job
When you set up your work area, make sure you define the area limits. High pressure water blasting is best done in a water jetting area.
During startup, make sure each member of the team is in position, direct the nozzle at the work piece, and hold the lance or gun securely. If you suspect there may be a problem (i.e., the water flow does not shut off when the trigger or foot pedal is released), stop work.
At any time during the job, stop work if:
You notice leaks or damage
There is a change in conditions or hazards
There is a plant or work emergency alarm
Work is not being done safely
Here are some other important points:
Use the minimum pressure required for the job
Never leave a pressurized system unattended
Never hold objects being cleaned in your hands
Use equipment only as intended (i.e., never use a hose to support your weight when climbing in or out of a confined space)
Never work with damaged equipment. Replace or repair anything that is damaged or worn. Remember-always depressurize the system before making repairs.
Use the right tool for repair (i.e., do not use adjustable tools like crescent wrenches or pliers as these may damage equipment). Make sure all pieces on the system fit and work together correctly. Never use makeshifts. Have equipment overhauled and checked for correct functioning at the manufacturer's recommended intervals.
For more information, refer to current applicable Occupational Health and Safety Legislation.