Transcript HandS Hydraulics Safety Awareness PowerPoint Presentation

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
Employee #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: 515205
Report ID: 0625700 -- 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: 145-315°C (300-600°F)
• High auto-ignition: 260-400°C (500-750°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: 967430
Report ID: 0932000 -- 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: 170587760
Report ID: 0950631 -- 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.
RISK ASSESSMENT
For every 1 degree in heat
applied to trapped hydraulic oil,
the pressure rises 50to 60-pounds-per-square-inch.
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: 170568448
Report ID: 0751910 -- 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
Working with Hydraulic Oils
• 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.
• 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.
RISK ASSESSMENT
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
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
Thank you
Dennis Mac
HandS UK Health & Safety Resources