Mechanical Hazards: Stored Energy

Hydraulic Line Check

(Source: Pennsylvania State University. Agricultural Safety and Health)

 

Use the following format to cite this article:

Mechanical hazards: Stored energy. (2013). Farm and Ranch eXtension in Safety and Health (FReSH) Community of Practice. Retrieved from http://www.extension.org/pages/66318/mechanical-hazards:-stored-energy.

 

Stored-energy hazards occur when confined energy is unintentionally released. A spring is a classic example of the release of stored energy: A compressed spring expands with great force when released, and a stretched spring quickly contracts. Springs, hydraulics, and pneumatics move and control machines and implements that are part of agricultural equipment. The sudden pressurization or depressurization of such stored-energy systems can result in incidents that cause serious injury or death.

There are many examples of stored energy in agricultural equipment:

  • Compressed air 
  • Pressure washers
  • Springs
  • Winches
  • Hydraulic, pneumatic, and electrical systems

Compressed air and fluids are used for tire inflation and power washing and in hydraulic cylinders. Springs are used as shock absorbers and as a means of keeping belts tight. Winches and hydraulic systems are used to lift or change the position of implements. 

Potential Injuries

Injuries that can result from the unintentional release of stored energy include burns, contusions, abrasions, lacerations, injection injuries (as from hydraulic fluid), and crushing injuries. Amputation of a limb may be required if an injection injury is not immediately treated at a hospital.

Safety Precautions

The list below outlines ways of reducing the risk of a stored-energy incident.

  • Identify machines that may have stored energy.
  • Before operating a machine that uses hydraulic or water pressure, examine the hoses and fittings for wear.
    • Pass a piece of cardboard (shown above) or flat board along the hydraulic hoses to check for leaks. Do not use a hand to check for leaks. Gloves do not provide protection from hydraulic leaks under pressure.
  • Turn off the engine and relieve hydraulic pressure before disconnecting hydraulic hoses or completing repairs.
  • Lower hydraulic components to the ground before shutting off the engine and dismounting the equipment.
  • Never walk under an implement or component supported by hydraulics or winches.
  • Regularly check winch cables for wear.
  • Before executing maintenance on hydraulic implements, put in place supports, jacks, stands, or blocks to prevent unintentional movement of the implements.
  • Know what direction a spring will move when released and how it might affect other machine parts, and stay out of the spring’s path.
  • Wait for free-wheeling parts such as flywheels, cutter heads, hammer mills, rotary mower blades, and fans to come to a complete stop before touching them.
    • This may take up to two and a half minutes.
  • Never try to stop a free-wheeling winch handle by catching it.
  • Never point a compressed-air nozzle or pressure-washer nozzle toward a person, including yourself.
    • Make sure others are well out of range of flying debris when using such equipment.

Resources

Click HERE to view a video about stored energy from Pennsylvania State University’s Agricultural Safety and Health Program.

Click HERE to purchase a video from the Fluid Power Safety Institute on managing hydraulic oil injection injuries.

 

Use the following format to cite this article:

Mechanical hazards: Stored energy. (2013). Farm and Ranch eXtension in Safety and Health (FReSH) Community of Practice. Retrieved from http://www.extension.org/pages/66318/mechanical-hazards:-stored-energy.

 

Sources

Agricultural equipment and machinery hazards. (2016) The Ohio State University. Retrieved from http://agsafety.osu.edu/programs/cfaes-osha/ag-equipment-machine-hazards.

Cyr, D. & Johnson, S. (2002) Dangers of agricultural machinery. Maine Farm Safety Program. Retrieved from http://umaine.edu/publications/files/2015/04/2316.pdf.

Harshman, W., Yoder, A., Hilton, J., & Murphy, D. (2011) Mechanical hazards. HOSTA Task Sheet 3.1. Pennsylvania State University Agricultural and Biological Engineering Department. Retrieved from http://articles.extension.org/sites/default/files/Version%203.%20January….

Safety note #16: Hydraulic safety. (2004) University of California, Agricultural and National Resources, Environmental Health and Safety. Retrieved from http://safety.ucanr.org/files/1406.pdf.

 

Reviewed and Summarized by:
Linda M. Fetzer, Pennsylvania State University – lmf8@psu.edu
Willard Downs, University of Missouri  Willard@missouri.edu
Dennis J. Murphy, Pennsylvania State University (Has since retired)
Robert A. Schultheis, University of Missouri  SchultheisR@missouri.edu
Aaron M. Yoder, University of Nebraska Medical Center – aaron.yoder@unmc.edu

Hydraulic Safety


Use the following format to cite this article:

Hydraulic safety. (2012) Farm and Ranch eXtension in Safety and Health (FReSH) Community of Practice. Retrieved from http://www.extension.org/pages/64565/hydraulic-safety.

Hydraulic systems on agricultural equipment are used to complete such maneuvers as lifting the buckets on skid steers or adjusting the position of combine headers. Hydraulic fluid moves through very small openings within an operating system, and it is under tremendous pressure that can exceed 2,000 pounds per square inch (psi). Some newer and larger pieces of equipment have hydraulic systems with pressures that exceed 3,000 psi. (Running water from a household faucet typically measures 40 psi.)

Hazards

Hydraulic systems and hydraulic fluid can be hazardous to workers in several common scenarios.

Improper Couplings

Never mix low- and high-pressure coupler components (that is, do not connect a low-pressure component to a high-pressure system). Mismatched componenets may cause a rupture in a hose or fitting.

Pinhole Leaks

Never use your hand to locate a leak in a hydraulic line. Because hydraulic fluid—often oil—is highly pressurized, compressed fluid released through a leak can penetrate the skin or eyes, causing severe injury, such as gangrene. Injection injuries from high-pressure hydraulic fluid require immediate medical care.

When trying to locate a leak in a hydraulic line, wear eye protection and gloves. Run a piece of paper, wood, cardboard, or Plexiglas along the hydraulic line (as shown below) to determine the location of the leak. Always relieve the hydraulic pressure in an operating system before detaching or attaching a hydraulic line to make necessary repairs.

Hydraulic Check with Plexiglass

(Source: Pennsylvania State University. Agricultural Safety and Health)

Component Removal or Adjustment

Release the hydraulic pressure in an operating system prior to removing or adjusting components. The hot fluid in the system is under extreme pressure. If a worker is exposed to hydraulic fluid while removing or adjusting components, he or she may sustain burns, bruises, cuts, abrasions, or injection of fluid into the skin.

Maintenance

Proper maintenance is critical for all types of machinery and equipment, but it is imperative that you follow proper safety measures when performing maintenance.

  • Wear personal protective equipment (PPE) when performing maintenance on hydraulic systems, including gloves and eye protection.
  • Do not rely solely on the hydraulic lift if you must work on hydraulic components with the system raised. Set the working unit on blocks as a precautionary measure.
  • Unless you are bleeding the hydraulic system, do not run the machine engine when you are servicing the system.
  • Hydraulic fluid can be extremely hot and can cause severe burns, so let the hydraulic system cool before changing lines, connections, filters, or fittings.
Bad Hydraulic Hose

Bad Hydraulic Hose

(Source: Pennsylvania State University. Agricultural Safety and Health)

 

  • Regularly examine the hydraulic lines for leaks and wear (as shown above). 
  • Coat the cylinder rods with a lubricant that provides rust protection.
  • Periodically replace filters, and keep hydraulic oil away from contaminants; dirt is the biggest culprit in hydraulic system damage.
  • Before removing the cylinders from working units, make sure that the units are resting on the ground, safety stands, or safety blocks and that the engine is shut off.
  • Use a chain hoist, floor jack, or other type of assistive device if you need to remove heavy hydraulic pumps or control valves.

Safe Operating Procedures

Follow these recommendations when using equipment with hydraulic systems:

  • Before leaving the machine, lower the hydraulic work unit to the ground and relieve hydraulic pressure by moving the control valve back and forth several times.
  • Park the machine in an area where children are unlikely to come into contact with it.
  • To keep the machine in place during transportation, lock the cylinder stops.
  • Use cylinder stops, locks, or blocks for raised equipment or components when servicing hydraulic components or performing maintenance.
  • To reduce the risk of escaping oil, make sure all the line connections within the system are tight.
  • Use a nonvolatile cleaning solution when washing parts.
  • Keep hydraulics properly adjusted for better control of the machine.

 

 

 

Use the following format to cite this article:

Hydraulic safety. (2012) Farm and Ranch eXtension in Safety and Health (FReSH) Community of Practice. Retrieved from http://www.extension.org/pages/64565/hydraulic-safety.

Sources

American Society of Agricultural and Biological Engineers (ASABE). (2008) ASAE S489 Hydraulic pressure available on agricultural tractors for remote use with implements. St. Joseph, MI. Retrieved from https://elibrary.asabe.org/.

Ayers, P. (n.d.) Hydraulic systems safety. Colorado State University Extension. Retrieved from http://nasdonline.org/static_content/documents/1100/d000891.pdf.

Harshman, W., Yoder, A., Hilton, J., and Murphy, D. (2012) Implements with hydraulic components: HOSTA Task Sheet 5.5. Pennsylvania State University Department of Agricultural and Biological Engineering. Retrieved from http://www.extension.org/sites/default/files/NSTMOP%20Task%20Sheets%20Se….

Safe use of hydraulic systems. (2006) The Ohio State University Extension, Tailgate Safety Training for Landscaping and Horticultural Services. Retrieved from http://nasdonline.org/139/d001703/safe-use-of-hydraulic-systems.html.

Safety management for landscapers, grounds-care businesses and golf courses (1st ed.). (2001) Moline, IL: John Deere Publishing.

 
Reviewed and Summarized by:
Linda M. Fetzer, Pennsylvania State University – lmf8@psu.edu
William C. Harshman, Pennsylvania State University (Has since retired)
Jason Lamm, Donegal Insurance Group  jgl134@gmail.com
Dennis J. Murphy, Pennsylvania State University (Has since retired)
Aaron M. Yoder, University of Nebraska Medical Center – aaron.yoder@unmc.edu