Monitors, TestersMonitors and testers are devices used to measure and monitor the level of static electricity in a clean room or other environment where sensitive electronic equipment is used. They are an important part of any ESD protection program, as they allow operators to ensure that the level of static electricity in the environment is within safe limits. Some common types of monitors and testers include ionizers, resistance meters, and field meters. These devices are used to measure the level of static charge on objects and surfaces, as well as the electrical resistance of materials used in the clean room environment. By using these devices, operators can ensure that the level of static electricity is kept within safe levels, and take appropriate measures to reduce it if necessary.