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Creepage and Clearance
International medical device electrical safety standard IEC 60601 has stringent requirements regarding the creepage and clearance distances between connector pins. Clearance is the straight-line distance (or air gap) between conductors and creepage is the shortest surface distance between conductors.
Clearance and creepage
These contact spacing requirements are based upon Means of Patient Protection (MOPP) standards. The IEC 60601-1 specification defines medical electronics that come into direct contact with the heart, like electrophysiology catheters, as Type CF devices, and demands that they comply with two MOPP (2MOPP) specifications, which dictate larger clearance and creepage distances — twice that of 1MOPP — to ensure patient safety.
Clearance and creepage requirements for MOPP (left) and 2MOPP (right) compliance.
IEC 60601 also mandates additional cautionary measures for connectors that mix power and signal level voltages, requiring additional space between power pins of opposite polarity and exposed conductive surfaces, as well as between power and signal pins.
Touch-Proof Compliance
Another requirement of the IEC 60601 standard is that connector contacts must be touch-proof (i.e., designed to prevent people from being able to readily touch the electrical contacts with their finger). Touch proof compliance

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