Most participants in a weigh-in in eight hours (multiple venues)

According to Official Guinness Records,

The most participants in a weigh-in in eight hours is 8,855 and was achieved by Kaiser Permanente, San Diego (USA) at 21 locations throughout San Diego, California, USA, on 26 April 2011.
The total weight measured was 457,928.71 kg (1,009,560 lb). Mean weight for an adult male was 92 kg (203 lb) and for an adult female it was 72.57 kg (160 lb).

For a complete list of 2011 records, please visit 2011 Guinness Records in United States.

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