EN 50270 specifies the electromagnetic compatibility (EMC) requirements for electrical apparatus used to detect and measure combustible gases, toxic gases, or oxygen. It applies to devices used in residential, commercial, light-industrial, and industrial environments, including hazardous areas. This standard covers normal operation and focuses on immunity and emission requirements, including tests for continuous and transient, conducted and radiated disturbances, and electrostatic discharges. It categorizes apparatus into Type 1 (residential, commercial, and light-industrial) and Type 2 (industrial). It does not cover apparatus for detecting dust or mists, scientific or laboratory analysis, process measurement, medical purposes, breath alcohol measurement, or automotive exhaust gases. The standard prioritizes product-specific requirements over generic EMC standards.