For the Sustainable Sites Credit, Light Pollution Reduction, fixtures with a minimum of 1,500 lumens must be partially or fully shielded. This requirement helps to minimize light trespass and sky glow, contributing to the reduction of light pollution.
References: The LEED v4.1 O+M reference guide specifies the need for shielding on outdoor light fixtures to control light pollution.The threshold for lumens is set to ensure that lighting is designed to conserve the night sky1.
For the Sustainable Sites Credit, Light Pollution Reduction, outdoor light fixtures that directly emit light into the night sky and have a minimum lamp lumens exceeding 1,500 must be partially or fully shielded. This requirement is aimed at reducing light pollution by ensuring that outdoor lighting fixtures are designed and installed in a manner that minimizes sky glow and light trespass, thereby preserving the natural night environment.