Why are my electrometer measurements noisy?

Why are my electrometer measurements noisy?

Noisy readings are usually caused by electrostatic interference. Electrostatic interference is probably the most common source of error when making electrometer measurements. Electrostatic interference occurs when an electrically charged object is brought near an uncharged object. Since high resistance materials do not allow charge to decay quickly, noisy measurements may result. The unstable measurements may be due to either DC or AC electrostatic fields. Electrostatic shielding will help minimize the effects of these fields.