EEC SE 7441 - Key Safety Points to Remember; Introduction to Product Safety Testing; The Importance of Safety Testing

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When testing with DC, always discharge the capacitance of the item under test and anything the
high voltage may have contacted--such as test fixtures--before handling it or disconnecting the
test leads.
HOT STICK probes can be used to discharge any capacitance in the device under test as a further
safety precaution. A hot stick is a non-conducting rod about two feet long with a metal probe at
the end that is connected to a wire. To discharge the device under test, two hot sticks are
required. First, connect both probe wires to a good earth ground. Then touch one probe tip to the
same place that the return lead was connected. While holding the first probe in place, touch the
second probe tip to the same place where the high voltage lead was connected.
1.3.6 Key Safety Points to Remember
 Keep unqualified and unauthorized personnel away from the test area.
 Arrange the test station in a safe and orderly manner.
 Never touch the product or connections during a test.
 In case of any problem, turn off the high voltage first.
 Properly discharge any item tested with DC before touching connections.
1.4 Introduction to Product Safety Testing
1.4.1 The Importance of Safety Testing
Product Safety Tests are specified during the design and development stages of a product as well
as in the production of the products to insure that it meets basic safety requirements. These tests
are designed to verify the safety of the electrical products in that they do not jeopardize the safety
of the people, domestic animals, and property of anyone who may come in contact with these
products. In an era of soaring liability costs, original manufacturers of electrical and electronic
products must make sure every item is as safe as possible. All products must be designed and built
to prevent electric shock, even when users abuse the equipment or by-pass built in safety
features.
To meet recognized safety standards, one common test is the "dielectric voltage-withstand test".
Safety agencies which require compliance safety testing at both the initial product design stage
and for routine production line testing include: Underwriters Laboratories, Inc. (UL), the Canadian
Standards Association (CSA), the International Electrotechnical Commission (IEC), the British
Standards Institution (BSI), the Association of German Electrical Engineers (VDE) and (TÜV), the
Japanese Standards Association (JSI). These same agencies may also require that an insulation
resistance test and high current ground bond test be performed.