Sewer jetting is a serious business that can result in serious injury or death when proper safety precautions are not followed. Awareness of common jetting hazards, knowing how to protect oneself from them, and learning and practicing the proper safety procedures can greatly reduce the chances of disaster striking at unexpected moments.
Common Jetting Hazards
When water is pressurized to 4,000 PSI, it becomes a potentially deadly force that can easily result in serious injury when the water jet comes into contact with skin or eyes.
In early 2012, a plumbing company employee was cleaning a sewer and was struck in the neck with a jet of high pressure water and literally bled to death before he could receive emergency medical treatment.
Others have died after being struck in the head by a jetter nozzle that was pulled from a drain pipe before the water was turned off.
Improper use of a high-pressure water jetter can result in contamination by waste in the pipe itself.
Jetting can also take a toll on hearing when sound levels exceed 90 decibels. Sewer jetting is often done in confined spaces, which presents additional hazards on top of those already mentioned. Remember that all applicable OSHA rules for confined space entry and personal protective equipment must be followed.
Proper dress is also important when performing high-pressure water jetting. Coveralls should be worn. A heavy duty raincoat should also be worn to keep technicians dry and to help provide a barrier in the event there is contact with debris flying from the pipe.
Safety goggles should always be worn to protect the eyes from a high pressure jet of water. Water pressure above 2,000 PSI requires a full face shield, and at 4,000 PSI the water jet can literally tear an eyeball from its socket.
Heavy duty, waterproof gloves are needed to protect the hands. Rubber boots with metatarsal guards are highly recommended. Hard hats are necessary in environments where falling objects are a potential hazard.
Residential and commercial drains are cleaned from the top of the system, where the water flow originates. The drain technician can no longer put the hose into the pipe, let it enter the pipe for a distance, and then retrieve the hose completely. The hose cannot be retrieved completely because it will pull the obstructions back to the cleanout or plumbing fixture – high water pressure may blow the obstruction (and a lot of water) out of the pipe, causing potential injury and a large mess. To prevent this, the hydro-jetter must be turned off several times during the procedure. Turning off the water allows the water and debris in the pipe to seek a lower level and flow away from the pipe opening.
When starting a jetting job, it is extremely important to remember that a jetter hose must be placed into the pipe a minimum of three feet before the high pressure pump is engaged. If this is not done, the jetter hose can possibly exit the pipe prematurely and serious injury may result.
Conversely, the water pressure must also be turned off when the jetting hose and nozzle come within a minimum of three feet from the pipe opening when retrieving the hose. Otherwise there is the same risk of the hose exiting the pipe under full pressure and causing injury – several years ago, a city worker in Iowa was killed because he failed to use this procedure at the end of a sewer jetting job. It is easy to forget what can happen when a steel jetting nozzle is at high pressure and unrestrained – the nozzle can become a deadly missile, and in this unfortunate incident it happened in just this manner.
When cleaning larger municipal sewers with a high-pressure sewer jetter, it is a good idea to also put an anti-turn around leader on the end of the hose. An anti-turn around leader is a 2-3 feet long threaded pipe with a coupling that can be connected to the end of the jetting hose. The jetter nozzle is then attached to the end of the leader. The anti-turnaround leader will prevent the jetter hose from entering a service lateral pipe and possibly causing damage.