First among equals

A common in feature in the electrical industry just like in any other industry is the replacement of the specified products by alternatives that are deemed as 'equal and approved.' But certain factors need to be kept in my mind before using alternatives, such as energy performance and light distribution through electrical safety and maintenance requirements and aesthetic appearance. Three leading lighting organizations in United Kingdom, the Lighting Industry Federation, the Institution of Lighting Engineers, and the Society of Light and Lighting have come up with guidelines for using alternatives. The guidelines are outlined.