Safe Use of Hydro Excavators

Safe Use of Hydro Excavators

Introduction
Hydro Excavation is the process of removing or moving soil with pressurized water. An air conveyance or vacuum is then used to transfer the soil or debris to a debris tank. This allows for a non-destructive and more accurate way to excavate soil and locate underground utilities.

The popularity of hydro excavation today started with oil and gas industries in Canada. The Canadian contractors were able to see the efficiency of hydro excavation as compared to other methods of daylighting.

The cold weather in Canada often caused the soil to be frozen. This made it harder to excavate using traditional methods. Canadian contractors discovered that using hydro excavation with heated water was a good way to get the job done.

How Hydro Excavation Works
Hydro vacuum, or hydro-vac, excavation equipment combines high-pressure water and air vacuum. This system cuts through the soil and breaks it up. The vacuum then lifts the slurry from the excavation area. The debris is transferred to a debris tank. Hydro-vac excavation equipment also combines high-pressure air and air vacuum. The dry system disturbs and cuts the soil with air and breaks it up with the vacuum lifting the soil from the excavation area, transferring it to a debris tank.

Hydro-vac excavation equipment needs a vacuum source. There are two choices for this, a fan system, or a positive displacement blower. A fan system can move air in huge amounts. This allows for faster excavations. It is easier to control and operate. This is often lighter and less expensive than the positive displacement blowers.

Applications
Underground facilities and subsurface utilities are almost always needed for construction. Excavation to lay these utilities is not an easy job and has a lot of risks. The existence of hydro-vac excavation has considerably lessened these risks and it can now be used for several excavation applications.

Hydro-vac excavation is used for line, sign and pole installation and location. It is also used for potholing or daylighting. It allows for less congestion and traffic in the excavation area because the equipment can be positioned at a distance. Pipe and sewer rehabilitation is another application for hydro-vac excavation. This method reduces risks for any damages to or punctures in the pipes. This eliminates the additional time and cost those repairs require. By using hydro-vac excavation for landscaping, accurate excavation is done so the surrounding soil is not disturbed. Soil stays compact and strong while necessary removal is completed.

Benefits
Hydro vacuum excavation brings several benefits to the industrial excavation world. It is now the most preferred method of digging because of its efficient and accurate results. The primary benefit of hydro-vac excavation is that it provides for better damage and safety control when compared with mechanical methods. Since it is accurate, it limits accidents and injuries for laborers as well as other people. It also does a better job of digging.

Using hydro-vac excavation avoids damage to underground pipes, lines and cables. This in turn eliminates the high expenses needed for repairs and restoration. Needing to do fewer repairs means less time to get the job done too. Interrupted utilities bring inconveniences and high costs. This process of excavation can minimize damages. Hydro-vac excavation provides a way of digging and moving soil in a safer manner. It is a non-mechanic
and non-destructive method. The laborers will be safe from machinery accidents and the citizens nearby will be safe from construction mishaps.

Hydro-vac excavation only involves water and an air vacuum. The equipment for this process can be positioned at a distance from the actual excavation area. This lessens traffic and congestions at the excavation site.

All these bring long run benefits as well. With the safety risks and repairs lessened, hydro-vac excavation also reduces insurance and liability costs. As this process provides better results, a company’s reputation and profitability often increases. In general, hydro-vac excavation is a method that creates a better service for the customer and makes life easier for the contractors, the customers, and the laborers.

Hazards
Although generally safe to operator, Hydro-vac Excavators are still dangerous pieces of equipment to use and can cause critical injuries or fatalities as well as damage to utilities and buildings. Some of the hazards associated with the use of Hydro-vac Excavators include:
• Fall Hazards from Heights while operating near trenches, excavations, holes and other openings causing injury to operators
• The wand and/or high-pressure water jet can strike an operator causing cuts and critical injury or fatality if not used with a dead man trigger or gun operator-controlled device
• During rotation, the boom can strike an operator causing significant injury
• During operation the boom can strike overhead power lines causing electrocution, fire and explosion
• Vacuum during operation can suck you in causing crush hazards
• Water pressure can cause potential slip hazards due to surfaces
• Water pressure can cause serious injuries in event operator encountering the water due to high velocity impact or accidental movement of the nozzle
• Workers can fall into excavated holes

Personal Protective Equipment
Personal protective equipment helps protect the worker. The following PPE must be worn:
• CSA Approved Hard Hat
• CSA Approved Eye Wear or Goggles
• CSA Approved Face Shield
• Rain Suits
• CSA Approved Safety Footwear with Metatarsal Protection
• Hearing Protection
• Hand Protection (Gloves)
• Reflective Vest

Safe Procedures

Operators
The Hydro-vac Excavator should be operated by a team of two: Driver and Swamper. A Competent Operator is defined as one who has training, knowledge and experience on the equipment being used, knows the hazards and the dangers associated with the machine and the Legislation and applicable Regulations and Standards associated with the machine. All operators of Hydro-vac Excavators must complete a training program prior to using the
equipment. This training must be provided by a competent person.

Competent operators are aware of the hazards of the machine being operated and know how to protect themselves and others while operating the machine. Refresher training ensures that operators are kept up to date with Legislative requirements as well as changes to machines.

Daily Inspections
Operators must complete a daily vehicle inspection and truck equipment and tools to ensure all equipment is working effectively before leaving the yard. Operators must ensure there are no loose or missing parts and that all parts are securely fastened, there are no visible leaks and excessive wear, and they must inspect all structural members for cracks, excessive corrosion, and other damage. If the machine is damaged and requires service, do not use the machine and report the defects to your Supervisor.

Operation
Measures and procedures must be put into place regarding the type of work performed and hazards associated with the work, vehicle, and environment. This includes:
• On route to the site
• Arrival at the site
• Traffic control and safety and vehicle reversing
• Using the Hydro-vac Excavator
• Digging near power lines
• Dumping

Consider the following:
• Ensure a pre-start daily safety assessment is completed and reviewed with workers
• Ensure workers are trained to use the equipment
• Ensure guards and safety features such as remotes, safety latches on triggers, use of
wands and nozzles that can be stopped at the trigger.
• Swampers must signal the Driver when reversing onto the road and stay a minimum 3 metres from truck when reversing.
• Once mobile, swampers must be always in the truck with the Driver.
• Operators must obtain locates and review them prior to starting work
• If using hot water, never exceed 115 degrees Fahrenheit or 2500 psi
• Drivers must ensure they keep the boom and vehicle a minimum distance of 3 metres (10 feet) from any power lines when operating the boom into position.
• Drivers must ensure water pressure is always monitored and equipment is calibrated and working correctly.
• The maximum water pressure to be used at any time with a spinning tip nozzle during excavation is 3000 psi.
• Operators must always ensure the wand is always held while performing the Hydro-vac Excavation and Jetting function.
• Always assume that all utility lines are live unless otherwise expressly identified by the utility on the locate
• Dumping must be done in approved locations only

Emergency Procedures
Ensure you investigate all incidents involving the use of the Hydro-vac Excavator immediately and report any injuries or fatalities to the Ministry of Labour and/or WSIB as required by Law.
In case of Injury:
• Contact 911 and provide first aid treatment if qualified.
• Always remember to protect yourself and the worker from further danger if possible.
• Shut down the equipment if possible and provide comfort to the injured worker until emergency services arrive.

If damage to the utility line occurs including the coating:
• Leave the utility line exposed, barricade the area and contact the utility immediately.
• Call 911 and keep the area clear.