Presentation on theme: "Hydraulics Safety Awareness Dennis Mac HandS UK Health & Safety Resources."— Presentation transcript:
Hydraulics Safety Awareness Dennis Mac HandS UK Health & Safety Resources
Hydraulics is not a recognised occupational hazard Unless there is a lost time injury or a death, hydraulic "accidents" go unreported Result = no data No data = no recognised problem
But there is a problem. Each of the cases illustrated here is an accident that could well occur in your company. The first step in preventing these, as with all types of accidents, is training.
Hydraulic systems store fluid under high pressure – typically, at 2,000 pounds per square inch… Hazards: stored energy flailing hydraulic hose, ejected components maintenance conducted without releasing pressure maintenance conducted after incorrectly releasing pressure temperature ignition injection
Employee Killed By Forklift Boom E mployee #1 was unloading a piece of steel with his forklift. His supervisor leaned down to unhook a chain and saw hydraulic fluid dripping from the joint at the main cylinder; he told Employee #1 to take the forklift to be fixed by the maintenance man. The employee parked the forklift in the maintenance area and raised the forks. Employee #1 was standing under the forks when the hydraulic fitting to the mast failed, resulting in a sudden release of the fluid and descent of the mast. Employee #1 was killed. No one saw the accident. He may have been attempting to pinpoint the leak's location prior to summoning the maintenance man. There was a wrench on the floor near the body, and it is likely that Employee #1 was attempting to tighten the fitting to stop the leak, but instead stripped the threads, causing a complete failure. OSHA Accident: Report ID: Event Date: 09/18/1990
Skin will scald at 48°C (120°F)… Two to three minutes at that temperature will result in a 2nd degree burn. The average operating temperature of a hydraulic system of 60°C will cause a 2nd degree burn in ½ to 1 second.
Oil adheres to the skin. The longer the contact, the deeper the burn. Burn injuries are the worst type of injury from a rehabilitation point of view. The rule of thumb is: one day in hospital for each 1% of body area burned.
This operator was burned when a hydraulic hose, neglected during maintenance, burst and spewed hydraulic oil, at normal operating temperature, over his entire body.
Fire and Explosion Risks High flash point: °C ( °F) High auto-ignition: °C ( °F) Under pressure, atomised spray of droplets may extend 10 metres from the break Ignited readily by heat source Resulting fire is torch-like with very high heat release rate Mist in confined area can explode violently
Welder Strikes Hydraulic Fluid And Is Burned To Death Employee #1 was arc welding in the forward ballast tank of the American Trader vessel, working approximately 68 feet from the upper deck in an enclosed space. His welding rod struck a pipeline containing hydraulic fluid, which was under approximately 600 psig at the time, and ignited a fire. Employee #1 became engulfed in flames, and sustained thermo-cutaneous burns over 80 percent of his body from which he died. OSHA Accident: Report ID: Event Date: 07/18/1991
Two Employees Burned In Flash Fire Employees #1 and #2, both press operators, were operating an aluminum extrusion press when a hydraulic hose developed a leak. Hydraulic fluid sprayed out in a small stream under pressure and then partially vapourised. The heat and flame from a nearby oven ignited the fluid, resulting in a flash fire. Employees #1 and #2 sustained second- and third-degree burns. OSHA Accident: Report ID: Event Date: 02/19/1996
Imagine a chip pan fire… Projected from a high-pressure nozzle…
The frequency of fires involving hydraulic fluids has prompted the introduction of fire-resistant fluids for hydraulic systems. Is your company using them?
Never heat or weld on or near hydraulic components without proper preparation. For every 1 degree in heat applied to trapped hydraulic oil, the pressure rises 50- to 60-pounds-per-square-inch. RISK ASSESSMENT
Employee Dies In Oil Drum Explosion Employee #1 was cutting the top out of a 55 gallon metal drum that had contained hydraulic oil. The drum exploded, killing the employee. OSHA Accident: Report ID: Event Date: 06/09/1995
Never use hands or fingers to find leaks. Fluid under high pressure can be injected into the skin causing extreme injury, serious infection – gangrene – and amputation.
Accidental Injection of Hydraulic Oil
Pipe being pressure-tested in rig with OM15 aircraft hydraulic oil, held at 6,000psi… As operator reached inside Perspex box to operate pressure relief valve, hand brushed against pipe to valve, just as the pipe split. Fine jet of oil made a ¼-inch cut in hand, with ½-inch circle of lifted skin around it. Felt like being punched in the palm. No pain…
Rushed to hospital in company security van Pain increasing; intravenous pain relief In surgery 5 hours after incident, began removing oil After surgery, morphine ineffective for pain relief With local anaesthetic to hand, undid stitches and searched for more oil Second surgery on day three
Skin turned black on little finger Carpal tunnel opened to relieve pressure Massive swelling crushing nerves Cut away side of hand “eaten” by oil Third surgery on day five More flesh cut away and grafts begun Drugs for pain finally working
14 days in hospital Weekly physiotherapy 3 months later, fourth surgery to release little finger that had curled into palm 9 months later, fifth surgery Off work for six months 3 skin grafts with scarring to thigh and arm 2 years of physiotherapy Marriage break-up
Pipe, retrieved from dismantled test rig
Avoid prolonged breathing of its vapour, mist, and fumes. Avoid prolonged or repeated skin contact. Use chemical-resistant gloves, splash goggles and a chemical-resistant apron Elevated processing temperatures may cause release of toxic vapours which are harmful if inhaled. Before working with hydraulic oil, know the location of the nearest emergency shower and eyewash station. Working with Hydraulic Oils
Wash off affected skin, eyes, and protective clothing immediately. Remove contaminated clothing, and launder or dry-clean it before reuse. After contact with hydraulic oil (and especially before breaks and meals, and at the end of shifts), always cleanse skin with a waterless hand cleanser, and then wash with soap and water.
Working with Hydraulic Systems Never begin work on a hydraulic system until fully trained. Never begin work on a hydraulic system without a Risk Assessment. Carefully review the manuals on equipment before beginning work. Ask questions about anything you do not fully understand. Review all Material Safety Data Sheets (MSDS) for all chemicals used. Maintain a clean work area free of slipping hazards and debris. Use all required safety equipment.
Block, secure or lower to the ground components that may move, rotate or fall. Use test equipment designed for higher pressures than the system being repaired. Use of gauges, lines, connectors, etc., designed for lower pressures can result in bursting or equipment damage. Start with high pressure gauges and work down. (A good rule is to use equipment rated at twice what is expected. Example: For a 2500 psi system, use a 5000 psi gauge.) Relieve system pressures. DO NOT USE FINGERS OR HANDS to find leaks. Check for leaks using a piece of cardboard or wood.
Always use safety glasses. Use extreme caution when disconnecting hydraulic lines. Severe burns from hot fluid can result. Clean up spills immediately. Hydraulic fluid can cause slips, falls and resulting injuries. Do not work under equipment / apparatus being supported by hydraulics. Stops, safety pins, etc, must be in place before repairs begin. AVOID HEATING NEAR PRESSURISED FLUID LINES.
Hydraulics Maintenance All hydraulic hoses, tube lines and fittings should be periodically inspected. Any deterioration should be carefully examined to determine whether further use of the component would constitute a hazard.
Conditions such as the following should be sufficient for consideration of replacement: a. Any evidence of hydraulic oil leakage at the surface of a flexible hose or its junction with the metal and couplings; b. Any blistering or abnormal deformation to the outer covering of a hydraulic hose; c. Hydraulic oil leakage at any threaded or clamped joint that cannot be eliminated by normal tightening or recommended procedures
and/or d. Evidence of excessive abrasion or scrubbing on the outer surface of a hose, rigid tube, or hydraulic fitting.
Summary The risks of work with hydraulic systems are not only of high-pressure puncture accidents, but of fire, lacerations, severe burns, crushing and death. These risks apply not only to test-bed engineers, but to maintenance fitters, forklift and lorry fitters, millwrights, platers and welders… and to anyone whose work entails the operation of machines – whether they be milling machines or bulldozers – that use hydraulic pressure systems.
All maintenance work should be visually examined when Risk Assessed. All "hot work" should be visually examined when Risk Assessed. the presence of a hydraulic system is a hazard the presence of hydraulic hoses is a hazard RISK ASSESSMENT
Remember? Step 1: Look for the hazards Step 2: Decide who might be harmed and how Step 3: Evaluate the risks and decide whether the existing precautions are adequate or whether more should be done Step 4: Record your findings Step 5: Review your assessment and revise it if necessary HSE, “5 Steps to Risk Assessment”, INDG 163
Poor skills, not poor employees, are the root-cause of most accidents associated with hydraulics. There is no tool more effective at eliminating poor skills and hence, work-related accidents, than training.
Ensure that only trained, authorised persons carry out hydraulic system service, repair and troubleshooting. Encourage discussion in management and in safety committees on the need for training that will prevent these kinds of accidents occurring to those to work near or with hydraulic systems.
Get training for competency in hydraulics Get training - not in the theory of hydraulics - but in the hazards of hydraulics
Hydraulics Safety Awareness Dennis Mac HandS UK Health & Safety Resources Thank you