With ever more sources of electromagnetic radiation being produced, equipment must be designed to operate in noisy electro-magnetic environments.
It's also important that they don't cause radio-frequency disturbance in other equipment.
This is the essence of electromagnetic compadibility (EMC). Inadequate EMC can result in errors and incorrect operation of electronic devices; an increase in hazardous situations and consequently a higher health and safety risk.
Standards can help you ensure that your products will operate safely and effectively in the real world.