The Environment Ministry on Friday announced changes to government guidelines on the management of light pollution to help mitigate the impact of light pollution on the environment.

The ministry says that revised guidelines include recommended values on upper limits of the color temperature of street lights. Color temperature, measured in Kelvin (K) describes the color of visible light. The ministry’s Department of Atmospheric Environment says that higher color temperature tends to be whiter and brighter, while a yellowish color means light is warmer and less glaring. 

The updated guidelines state that the color temperature of street lights in national parks, nature reserves, and ecological conservation areas should not be higher than 3000K. For all other roads, the color temperature should be 3500K.

Additionally, guidelines also suggest that the flashing lights from billboards should be kept below recommended levels in commercial areas from 6 p.m. to 11 p.m. and switched to static after 11:00 p.m. to reduce disturbance.

The ministry adds that the guidelines do not come with penalties and are to be implemented by relevant authorities depending on the location.