Define: Coefficient Of Utilisation

The coefficient of utilisation (CU) is a measure used in lighting design to determine the efficiency of a lighting system in delivering light to a specific area or task.

The coefficient of utilisation is calculated by dividing the total luminous flux received on the working plane by the total luminous flux emitted by the lamps.

The coefficient of utilisation helps designers determine the effectiveness of a lighting system in providing adequate illumination for a given space. It helps optimise lighting layouts and minimise energy consumption.

The coefficient of utilisation is influenced by various factors, including the type and placement of luminaires, room dimensions, surface reflectance, and the presence of obstructions or furniture.

To improve the coefficient of utilisation, you can consider using more efficient luminaires, optimising their placement, selecting appropriate reflectance values for surfaces, and minimising obstructions that may block light.

Yes, there are industry standards and guidelines, such as those provided by the Illuminating Engineering Society (IES), that offer recommendations and methodologies for calculating and achieving desired coefficient of utilisation values.

While the coefficient of utilisation itself does not have direct legal implications, compliance with lighting regulations and standards that may reference or require certain coefficient of utilisation values is important to avoid potential legal issues.

Yes, the coefficient of utilisation can be used as evidence in legal disputes related to lighting design, particularly if there are allegations of inadequate lighting or failure to meet regulatory requirements.

It is highly recommended to consult a lighting professional, such as a lighting designer or engineer, who has expertise in calculating and optimising the coefficient of utilisation for your specific project. They can ensure compliance with regulations and help achieve the desired lighting performance.