Put your hands in the food bag first. Under normal circumstances, hands and bags will not stick together.
Then, turn on the hair dryer at work. Put your hands in the food bag.
10 seconds later, if the bag and hand stick together, it means that negative ions can be generated.
Because different negative ion generators produce different negative ion concentrations, the phenomenon will be different.
If the concentration of negative ions is large enough, there is another way. Apply the electric pen to the mouth of the negative ion generator for 3 cm,
The pencil will light up.