Fora GD40 Owner's Manual page 3

8. Use of this instrument in a dry environment, especially if
synthetic materials are present (synthetic clothing, carpets
etc.) may cause damaging static discharges that may cause
erroneous results.
9. Do NOT use this instrument in close proximity to sources
of strong electromagnetic radiation, as these may interfere
with the accurate operation.
KEEP THESE INSTRUCTIONS IN A SAFE PLACE
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