Assembly Installation and Procedures | SAFETY FIRST
The purpose of this article is to increase awareness on the proper installation and handling of hose assemblies, and to alert fabricators, installers, and end-users to the safety hazards in the field.
All hose has a finite life and there are a number of factors, which will reduce its life. The design and use of systems, which contain hoses, require consideration of factors related to specific application requirements.
Safety Considerations
Below are some potential conditions that can lead to personal injury and property damage. This list is not inclusive. Consider reasonable and feasible means, including those described in this section to reduce the risk of injuries or property damage.
Employers with hose assemblies in fluid systems are encouraged to provide training, including the information in this document, for maintenance personnel and other employees working with and around hoses under pressure.
1. Media Permeation
Hoses should always be used in well-ventilated areas. Certain media will permeate through hoses that can displace breathable air in confined spaces. Consult the manufacturer if in question.
Employers with hose assemblies in fluid systems are encouraged to provide training, including the information in this document, for maintenance personnel and other employees working with and around hoses under pressure.
2. Fluid Injections
Fine streams of pressurized fluid can penetrate skin and enter a human body. Fluid injection wounds may cause severe tissue damage and loss of limb. Consider the use of guards and shields to reduce the risk of fluid injections.
If a fluid injection occurs, contact a doctor or medical facility at once. Do not delay or treat as a simple cut. Fluid injections are serious injuries and prompt medical treatment is essential. Be sure the doctor knows how to treat this type of injury.
Avoid all contact with escaping fluids. Treat all leaks as though they are pressurized and hot or caustic enough to burn skin.
3. Whipping Hose
If a pressurized hose or hose fitting comes apart, the loose hose end can flail or whip with great force, and fittings can be thrown off a high speed. This is particularly true in compressible gas or fluid systems. If the risk of hose whipping exists, consider the use of guards and restraints.
4. Fire and Explosions from Conveyed Fluids
All hydraulic fluids, including many designated as “Fire Resistant”, are flammable (will burn) when exposed to the proper conditions.
Fluids under pressure, which escape from system containment, may develop a mist or fine spray that can explode upon contact with a source of ignition (e.g.; open flames, sparks, hot manifolds.) These explosions can be very severe and could cause extensive property damage, serious injury or death. Care should be taken to eliminate all possible ignition sources from contact with escaping fluids, fluid spray or mist, resulting from hydraulic system failures. Select and route hoses to minimize the risk of combustion.
5. Fire and Explosions from Static-Electric Discharge
Fluid passing through hose can generate static electricity, resulting in static-electric discharge. This may create sparks that can ignite system fluids or gases in the surrounding atmosphere. Use hose rated for static conductivity or a proper grounding device. Consult manufacturer for proper hose and coupling selection.
6. Burns from Conveyed Fluids
Fluid media conveyed in certain applications may reach temperatures that can burn human skin. If there is risk of burns from escaping fluid, consider guards and shields to prevent injury, particularly in areas normally occupied by operators.
7. Electrical Shock
Electrocution could occur when a hose assembly conducts electricity to a person. Most hoses are conductive. Many have metal fittings. Even nonconductive hoses can be conduits for electricity if they carry conductive fluids.
Certain applications require hose to be nonconductive to prevent electrical current flow. Other applications require the hose to be sufficiently conductive to drain off static electricity. Hose and fittings must be chosen with these needs in mind. Consult manufacturer with any questions.
Note:
Metal hoses are conductive. Always use proper grounding to minimize the risk of electrical discharge.
Note:
Be aware of routing hydraulic hose near an electrical source. When this cannot be avoided, nonconductive hoses should be considered. SAE J517-100R7 and 100R8 hoses with orange covers marked “Nonconductive” are available for applications requiring nonconductive hose.
8. Fluid Controlled Mechanisms
Mechanisms controlled by fluids in hoses can become hazardous if a hose fails. For example, when a hose bursts, objects supported by the fluid pressure may fall. If mechanisms are controlled by fluid power, use hose with design characteristics sufficient to minimize the potential risks of property damage or injury.
9. Hand-held Hydraulic Operated Tools
Extreme care is necessary when connecting hand-held or portable hydraulic powered tools to a hydraulic power source with a hose assembly.
- Always use a strain reliever at both ends of the hose assembly to prevent excessive bending, kinking and stress at the coupling to hose interface.
- Never use the hose assembly as a means to carry, pull, lift or transport the hydraulic tool or power unit.
- Exposed hose near the operator should be covered with a fluid deflection apparatus such as nylon sleeving, for protection against injection injuries should a hose rupture occur.
- Operators should be protected with the proper safety equipment such as face masks, leather gloves and safety clothing as dictated by the job, fluid and tools being used.
- If the connecting hose assembly could be subjected to external forces that may inflict damage, an appropriate guard should be used.