Hydraulic Safety

We are all surrounded by hydraulics every day. You will find hydraulic system in our cars and trucks.  In plant, machinery and construction equipment.

Hydraulics is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid counterpart of pneumatics, which uses gases.

The basic rule of using hydraulic power is Pascal's Principle. Pascal's Principle: pressure exerted on a fluid is distributed equally throughout the fluid.

This law states that if pressure is applied to a fluid that is confined in a small space, that pressure will be transmitted through the fluid in every direction without diminishing.  When it hits the edges of the confined space, the pressure will then act against that space at right angles.  Basically, a force acting on a small area can generate a proportionally bigger force on a bigger area.

Most hydraulic systems must store fluid under high pressure.

Three kinds of hazards exist: burns from the hot, high pressure spray of fluid; bruises, cuts or abrasions from flailing hydraulic lines and hydraulic injection of fluid into the skin.

What happened?

A person noticed a damp, oily, dirty place near a hydraulic line. Not seeing the leak, the person runs a hand or finger along the line to find it. When the pinhole is reached, the fluid was easily injected into the skin as if from a hypodermic syringe.


Immediately after the injection, the person experiences only a slight stinging sensation and may not think much about it. Several hours later, however, the wound begins to throb and severe pain begins.


By the time a doctor is seen, it is often too late, and the individual loses a finger or entire arm.

Safety Tips

  • Never use hydraulic equipment unless you are trained and competent to do so.
  • Keep high pressure on and check system visually for leaks before use
  • Always keep your face away from a possible leak
  • Never use your hands to find leaks
  • Always wear appropriate PPE- Gloves
  • Always wear appropriate PPE- Safety glasses
  • Never use damaged equipment
  • Switch off equipment before adjusting or cleaning it
  • Be careful not to crush or kink hoses as this can cause damage to the wire braiding that gives integral strength to hoses. The minimum bend radius is approximately 150mm
  • Never pressurise a hose that has a kink or sharp bend
  • Do not connect a high-pressure pump to a low-pressure system
  • Never push the check balls of couplers to drain hose pressure, even on unconnected hoses.
  • Always carry out a JSA/ SWMS/ JHA before commencing each job
  • If hydraulic oil has penetrated your skin consult a doctor immediately

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