EN 61000-6-4 specifies the emission requirements for electrical and electronic equipment intended for use in industrial environments, both indoor and outdoor. This standard does not apply to equipment covered by IEC 61000-6-3. It addresses emission requirements in the frequency range of 9 kHz to 400 GHz to ensure adequate protection of radio reception in the defined electromagnetic environment. Measurements are only necessary for frequencies where requirements are specified. The standard focuses on essential emission requirements to protect radio services, considering only relevant disturbance phenomena for equipment operating in these environments. Requirements are specified for each relevant port.