FLUID POWER SAFETY ALERT
Topic: Lack of proper hydraulic training by people "certified" to service mobile aerial lift equipment.
|Case history 1 -
"A quality control manager was using an aerial platform to collect material samples. He raised himself approximately 30 feet into the air to obtain the sample. As he began to lower the platform a failure occurred. The platform fell approximately 27 feet. The victim was ejected from the platform, and landed on the asphalt below. He suffered fatal injuries."
An investigation into the cause of the accident determined that the machine was not properly maintained.
|Do it or hit the road!:
Do it, or hit the road, is what a diesel mechanic was told by his supervisor after he explained to him that he was not adequately trained in hydraulics to perform repairs to the hydraulic systems on the companys rental fleet of mobile aerial lift equipment.
He was deeply concerned that because of his limited knowledge of hydraulics he might do something to a hydraulic system that could cause it to fail, and in turn, seriously jeopardize the operators safety.
The company, one of the largest rental companies in the Western US, apparently knew when they hired him to maintain their fleet of rental equipment, that he had no previous training in hydraulics. Yet, they went ahead and hired him promising to send him to numerous factory schools offered by the various manufacturers of the equipment they owned.
However, all the requests for training that he tendered were promptly declined citing poor timing, and staff shortages - they were simply too busy making money to have him absent from the workshop for a few days. In addition, there was no money in the budget for training.
On one occasion he was asked to find out why the mast on an aerial lift was drifting down. Through trial and error, he determined that the problem was a defective load holding/safety valve - it needed to be replaced.
The vehicle manufacturer did not have the valve in their inventory, and advised him that it would take at least two weeks before it would be available.
He reported the situation to his supervisor who balked at the idea of having the machine unavailable for rental for two weeks, and ordered him to piece it back together so it could be rented until the replacement part arrived.
The mechanic knew that the machine was defective and was clearly unsafe to use. Not only was the mast drifting, but he had disassembled and reassembled a safety valve that he knew nothing about.
He urged his supervisor to reconsider his decision to make the machine available for rental. However, his plea fell on deaf ears. In fact, the supervisor became agitated and told him to stop "whining."
He knew that what he had done might cause the hydraulic system to fail and seriously jeopardize the operators safety, so he hand wrote a "waiver of liability" and handed it to his supervisor to sign hoping that he might reconsider renting the defective machine out - but to no avail.
The supervisor reluctantly signed the note, and against the advice of the mechanic, the machine was subsequently rented to a construction company.
Case history 2 -
"A plant maintenance mechanic with no experience in hydraulics was asked to replace a leaking cylinder on the companys scissors-lift type personnel lifting machine.
To gain access to the cylinder the platform needed to be raised one or two feet off the ground. For safety, he made a support out of a number of 2 X 4s which he stacked on top of one another. He lowered the platform on to the makeshift support, and proceeded to remove the cylinder.
After he installed the new cylinder and tightened the hoses, he decided to remove the supports so he could test the machine. He reached in between the metal beams, and "punched" the stack of 2 X 4s out. The platform assembly collapsed crushing both his arms.
An inquiry into the cause of the accident determined that the contributing factors to the accident were:
- The victim was not properly trained to work on the hydraulic scissors-lift. In fact, he had no idea that hydraulic fluid supported the platform.
- The victims supervisor assumed that because he was a mechanic he knew how to service and repair hydraulic systems and components.
- The "homemade" support for the platform was inadequate.
No rules, no training, no accountability!
Surprised, dont be! Less than 5% of the people who service, repair, and troubleshoot the hydraulic systems on aerial platforms - the machines that elevate electricians, painters, sign makers, construction workers, aircraft mechanics, etc., in the air, are proficient in hydraulics, the very systems that propel the platforms 40-feet, to over 100-feet in the air - the majority cannot even read a hydraulic schematic.
Imagine what would happen if the aviation industry functioned under the same modus operandi - training for aircraft mechanics was purely at the discretion of "number crunchers." There is no doubt that airplanes would be falling out of the sky on a regular basis.
If a supervisor is a tightwad; has a personality conflict with a mechanic because he/she has a wart on the cheek; or, is intimidated at the thought of a subordinate being more technically competent than he/she is - no training!
Fortunately for all of us, the airline industry operates within the parameters of defined standards, along with rigid checks and balances. Aircraft mechanics have to be certified by FAA mandate, and profit-minded executives, managers and supervisors cant "buck the system" to "save" money, because the FAA is looking over their shoulders. Moreover, they are held personally accountable for the flying publics safety.
What you have to understand is the fact that the hydraulic aerial platform that you rent might very well be unsafe, Unlike the airline industry there are no standards, and no rules with respect to who can and cannot service and repair the equipment.
Case history 3 -
"A basket-lift vehicle belonging to an electric utility company had an inherent problem that caused the boom-swing mechanism to operate unpredictably.
Normally, the boom-swing movement is smooth and consistent (feathering), which is critical when maneuvering in close proximity of high voltage power lines.
However, in the case of this machine, the boom-swing movement relative to valve activation was totally unpredictable it would sometimes operate smoothly, and other times, would unexpectedly lunge out of control.
The personnel who used the machine reportedly complained about the problems with the boom-swing mechanism. The company in turn filed a complaint with the manufacturer. The manufacturer sent their technical representative to investigate the problem.
After conducting a series of tests, he concluded that there was nothing wrong with the machine, and gave it a clean bill of health! The utility companys safety department bought-off on the manufacturers inability to correct the problem, and put the machine into service.
The electrician who was "flying" the machine at the time of the accident also bought into the situation, because it was a well known fact amongst employees that this particular basket lift had a boom-swing control problem. The fact that he was "flying" it meant that he was willing to risk his life at the expense of a defective machine.
The victim was working on a 24,000-volt overhead power line. Apparently there is a 2-feet rule when working adjacent to high voltage lines. He was high above a roadway maneuvering the basket into position. He needed to make a slight horizontal adjustment so he activated the valve. Unfortunately, when he most needed to "feather" the boom-swing, it lunged unexpectedly, causing the basket to crash into the high voltage lines.
According to the flag person who was directing traffic down below, he heard an arc, and looked upward toward the basket. The electrician was engulfed in a ball of fire. He promptly called on his two-way radio for an ambulance."
An inquiry into the cause of the accident determined that the contributing factors to the accident were:
- The manufacturer failed to properly diagnose the problem.
- The manufacturer failed to repair the problem.
- The company failed to follow up with the manufacturer and insist on a permanent repair for the machine.
- The companys safety department failed to follow up on operator's complaints about the problem with the machine.
- The operators failed to demand that the machine be properly repaired.
Manufacturing plants are not educational institutions:
Its evident that no-one wants to take ownership of aerial-lift training. The various manufacturers of these machines offer training, but it is generally of such poor quality that it is, for all intents and purposes, ineffective.
They are not entirely at fault, because lets face it, they are not in the business of educating people. If our schools and colleges did a better job of teaching people "practical" hydraulics, the manufacturers service schools would be more beneficial.
Even if the manufacturers schools were excellent, you have the problem of convincing the owners of aerial lifting equipment the value of training. Most see training as nothing more than a "burden" on their respective maintenance budgets.
One aerial lift manufacturer in particular "certifies" people who graduate from their service training schools. Graduates receive a card stating which of their machines they are "certified" to repair and service.
However, the certification is nothing less than a token. One can receive their "certification" after completing as few as three hours of hydraulics training - this with absolutely no background in hydraulics!
We recently had one of these factory "certified" technicians in our troubleshooting workshop - his knowledge of hydraulic troubleshooting was, with all due respect to the technician, pitiful!
Mechanics are not necessarily to blame for the problem:
Please dont blame our hardworking mechanics for this problem. Mechanics want to do a good job. Most want to advance their skills. No, folks this is clearly a management problem.
The three most common excuses one hears from managers for failing to see to it that mechanics are properly trained are: there is not enough time; they fear they will have to pay them more; or, once they are trained they will look elsewhere for a better paying job.
Now, if one of those managers happened to find an interesting seminar that might coincidentally be held at or near a golf course, time would probably not be a factor in making the decision to take a few days off for "training."
Or, if they worked their tails off and earned an MBA, we are sure they would be beating the door down to get a salary increase - how things change when you are management - with all due respect!
Case history 4 -
"At the request of a power company, a dealer dispatched a field-service mechanic to troubleshoot a defective hydraulic system on an aerial-lift machine.
During the course of troubleshooting the machine, the pump housing literally blew apart. The field service mechanic traveled approximately 120 miles to pick up a new pump.
After installing the new pump, the mechanic started the machine. The new pump suffered a similar catastrophic failure on start-up. He returned once again to the dealership to pick up another pump. It also failed on start up,
The dealer dispatched another "more qualified" field-service mechanic to repair the machine.
The first field service mechanic had absolutely no hydraulic troubleshooting experience. He apparently tried to solve an actuator "slow-down" problem by overriding the main pressure relief valve setting. He did this by installing washers on top of the bias spring. He apparently associated the speed problem with a pressure deficiency."
The following factors contributed to the accident:
- The victim was not properly trained to service, repair, and troubleshoot hydraulic systems.
- The victim's supervisor assumed that because he was a diesel mechanic he knew how to service and repair hydraulic systems and components.
Are managers the root cause of the problem?:
It is safe to say that managers are the architects of the problems facing this country with respect to the looming shortage of skilled workers, because they determine budgets, and control the finances.
It will truly be a sad day for America when skilled workers arrive on our shores to take jobs away from extremely capable and proud American workers, only because their managers and supervisors failed to take a genuine interest in providing good training for them - this, by the way, is a well publicized prediction.
We vote that for every skilled worker who arrives on our shores, we "export" a manger who failed to see to it that our own blue-collar workers received the proper training!
Aside from the politics, our chief concern is that an untrained worker is at risk of suffering a job-related accident. And since many "managers" fail to see the value of proper training as a vehicle to giving people the ability to, amongst other things, work safely - we will do whatever it takes to protect them.
Given the facts in this Safety Advisory, what can you do to assure that the aerial platform that you own or rent is safe to operate?
- When you decide to purchase or rent an aerial lift platform, make a thorough investigation into the qualifications of the people at the local dealership. Find out if they are formally trained in hydraulics, and determine how many hours of training they have received.
Its no use purchasing a machine to learn afterwards that the people who service and repair it dont know what they are doing.
- Allow only trained, authorized persons to service and repair your machine. Have your purchasing department request copies of "certification" when ordering a repair or service. If the person has only on-the-job-training, dont let them touch it!
In addition, youre probably paying about $50 - $100 per hour for the service persons time, why pay that much for someone who is untrained?
- When a dealer or factory service person is working on your machine, make sure that they are wearing appropriate safety gear. Many dont even have the common etiquette to follow your safety rules and procedures, let alone any of their own.
- If they are troubleshooting your hydraulic system, make sure that they have the proper diagnostic tools and know how to use them. They should have suitable flowmeters, pressure gauges, etc.
If you see them "testing" a hydraulic pump by exhausting oil directly to atmosphere or into a bucket, or testing a cylinder by removing a transmission line and running the machine, give them their walking papers immediately.
Not only are they endangering themselves, but they are also teaching your maintenance people extremely bad habits!
- Never allow anyone to make parts substitutions without written permission from the manufacturer (NOT THE DEALER). This includes filters. Many people make filter substitutions based on cost. Filters are living proof that you get exactly what you pay for!
- Never allow anyone who is not properly trained in hydraulics to make adjustments to your machine.
- Maintain the machine in perfect working condition. If there are any operational problems such as erratic cylinder operation, or overheating, red-tag the machine and lock it out until the problem is rectified.
- Never operate a machine knowing that there is a problem with it, or it is defective. A persons life is literally riding on the decisions you make.
- Always ask for written test worksheets. If a dealer technician tests a hydraulic component(s), ask them for a copy of the test data sheet/s.
- Inspect the work. Make sure the machine is working perfectly. Do not sign the service report until it is.
- If you rent a machine inspect it when it arrives on site. Check for signs of visual damage, frayed hoses, leaking cylinder glands, leaking hydraulic components, correct oil levels, erratic operation, etc. If it is not operating perfectly, send it back!
- If you have reason to call a service person to attend to the machine while you are renting it, ask that the person bring along a certificate of training.
- Make sure that the rental company knows that you will hold them accountable for all non-injury and injury accidents.
- If there is an accident with the machine, DO NOT let the rental company remove it from your site. Conduct your own investigation first.
- WARNING - WE HIGHLY RECOMMEND THAT IF YOU HAVE NO FORMAL TRAINING IN HYDRAULICS, DO NOT SERVICE, REPAIR, AND OR TROUBLESHOOT THE HYDRAULIC SYSTEM ON PERSONNEL LIFTING DEVICES OF ANY KIND. IF YOU ARE NOT PROPERLY TRAINED, AND YOUR SUPERVISOR "FORCES" YOU TO SERVICE, REPAIR, OR TROUBLESHOOT THE HYDRAULIC SYSTEM ON A PERSONNEL LIFTING MACHINE CALL OSHA. THE WORK YOU DO COULD SERIOUSLY JEOPARDIZE THE SAFETY OF PEOPLE WHO OPERATE THIS TYPE OF EQUIPMENT.
What is the objective of this Safety Alert?:
First, peoples safety is the sole reason why we exist. We do not want to see innocent bystanders get hurt because of profit-minded supervisors and managers who have little or no respect for the safety of individuals and their families.
Our hard working mechanics invariably get blamed when things go wrong. Many, although they are highly qualified in a given field such as diesel engines, or transmissions, never have the opportunity to advance their skills - once again, generally because of profit-minded supervisors and managers.
Furthermore, we want the people who own and operate, or rent hydraulic aerial platforms, to be aware of the fact that there is a serious problem with respect to the skill level of many of the people who service, repair, and troubleshoot these machines.
Moreover, you can do something about it. Demand that the people who sell, and rent these machines train their technicians properly, if for no other reason than to provide a safe working environment for the people who operate them, and for the people who work around them.
While we have pulled no punches with respect to the problems associated with aerial lifting equipment, we respect the fact that there are many managers who are conscientious and caring about the fitness of their equipment, and the safety of their people - however, they are few and far between.
|The accidents we report are real, and the victims are real. The safety guidelines we provide are to help companies and individuals work safely with hydraulics. All guidelines we provide are general, and are not intended for one specific hydraulic system or machine.
WHEN YOU PURCHASE HYDRAULIC-POWERED MACHINERY AND/OR EQUIPMENT, WE HIGHLY RECOMMEND THAT ONCE YOU DETERMINE THAT IT CAN DO THE WORK YOU WANT IT TO DO, YOU THEN DETERMINE HOW MUCH SAFETY HAS BEEN BUILT INTO IT BY THE MANUFACTURER. IN ADDITION, WE RECOMMEND THAT YOU, WITH THE INPUT FROM YOUR OPERATORS, MECHANICS, ENGINEERS, PRODUCTION PERSONNEL, AND SAFETY DEPARTMENT, FORMULATE A LIST OF MINIMUM SAFETY STANDARDS FOR THE EQUIPMENT YOU PURCHASE. ALTHOUGH WE LIKE TO BELIEVE THAT MOST MANUFACTURERS ARE CONCEREND ABOUT SAFETY, SOME BELIEVE THAT CERTAIN SAFETY MEASURES ARE AN UNNECESSARY EXPENSE. WE FURTHER RECOMMEND THAT ALL THE SAFETY STANDARDS AND RECOMMENDATIONS THAT YOU DEVELOP SHOULD BE REVIEWED BY YOUR SAFETY DEPARTMENT, ENGINEERING DEPARTMENT, AND BY THE RESPECTIVE MACHINE OR EQUIPMENT MANUFACTURER PRIOR TO MAKING THEM POLICY - TOTAL SAFETY CAN ONLY BE ACHIEVED WITH A TEAM EFFORT.
|The Fluid Power Safety Institute does everything possible to insure that the information and drawings contained in these documents is accurate, and the procedures are deemed safe and reliable. However, these are general recommendations only and might not be applicable to all situations.
You MUST have your engineering department and service department read these recommendations and make the necessary changes for your specific application.
The Fluid Power Safety Institute is not responsible for actions taken by untrained and/or unauthorized persons. ALL hydraulic system service, repair, and troubleshooting should be done by trained, authorized persons ONLY.