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Design Safety

New equipment must be designed to conform to ISO 4413 (hydraulics) or ISO 4414 (pneumatics).

Examples (paraphrased; designers must comply to the actual wording of the standard):

  • Design for fail-safe operation, considering all possible modes of failure.
  • All components shall operate within manufacturer's specifications.
  • All parts of the system shall be protected against over-pressure.
  • Equipment shall incorporate an emergency stop or emergency return control, whichever provides maximum safety.
  • Emergency stops shall be readily accessible under all conditions of working and shall operate immediately.
  • Emergency stops shall not require that any actuator be energized.
  • Hydraulic circuits incorporating accumulators shall automatically vent the accumulator liquid pressure or positively isolate the accumulator when equipment is shut off.
  • If an accumulator is not automatically vented, complete information for safe servicing shall be given on or near the accumulator in a visible location, and duplicate information shall be provided on the circuit diagram.
  • Equipment shall be designed so that loss of electrical, pneumatic and/or hydraulic power shall not cause a hazard.
  • Neither surge pressure nor loss of pressure shall cause hazards.
  • Pump inlet temperatures should not exceed 60 deg C when maximum ambient temperatures exist.
  • Rotating parts shall be guarded to provide adequate protection against hazard.
  • Flexible hoses shall only be used where necessary. Their length shall be minimized and they shall be protected from abrasion. If failure causes a hazard, the hose shall be restrained or shielded.
  • Piping shall not be used for equipment support.