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3 Standards and Reference Criteria <br />Lighting adequacy was evaluated using criteria established by the Illuminating Engineering <br />Society of North America (IES), specifically as referenced in the City of Minneapolis Street <br />Lighting Policy, which is based on IES adopted RP-8-00 report (2® £¶ ¸ ,¨¦§³¨­¦ȩ. These <br />values represent typical ranges for illuminance targets in different types of urban settings, <br />as seen in Table 1 below. <br />Table 1 – IES Illuminance Targets <br />Area Type Illuminance Range (fc) <br />Residential Areas / Local Streets 0.30 – 0.60 <br />Pedestrian Areas 0.80 – 1.20 <br />Central Business District 1.50 – 2.00 <br />Since the study area is classified as residential local roadway, the 0.30 – 0.60 fc standard is <br />the primary criterion. However, values for other classifications are included as context. <br /> <br />4 Methodology <br />Measurements were conducted under nighttime conditions with minimal external <br />influences. The moon phase and sky clarity are noted for each observation, as moonlight can <br />temporarily elevate ground-level illuminance and skew comparison to standards. <br />Additionally, measurements were conducted during a period of astronomical darkness, <br />defined as the time when the sun is more than 18 degrees below the horizon and no <br />scattered sunlight contributes to sky brightness. Conducting the study under these <br />conditions ensures that readings reflect only artificial lighting sources, without influence <br />from twilight or residual natural light. <br />Readings were taken with the light meter positioned directly on the pavement, beneath <br />representative lighting locations or beneath the horizontal illumination of existing lights, in <br />order to capture maximum illuminance values. This approach provides a consistent method <br />to compare relative lighting levels between different lighting locations described below. <br />Four locations included for this study are: <br />&´«§ ¬ 3³±¤¤³ lj 3®´³§ ΒΕ 3¤±µ¨¢¤ $±¨µ¤ Ȩ3³´£¸ !±¤  ΐȩȀ The area under evaluation. <br />- ±¨®­ 2® £ lj 3®´³§ ΒΕ 3¤±µ¨¢¤ $±¨µ¤ Ȩ3³´£¸ !±¤  ΑȩȀ The area under evaluation. <br />&´«§ ¬ 3³±¤¤³ lj & ¨±¶ ¸² , ­¤ Ȩ%·¨²³¨­¦ 3³±¤¤³«¨¦§³ȩȀ A location with a recently <br />installed streetlight to establish a baseline condition that is known to comply with IES <br />guidance. <br />!¢®±­ 2® £ Ȩ.® 3³±¤¤³«¨¦§³ȩȀ A roadway segment without streetlighting and with minimal <br />surrounding light pollution, providing a lower boundary of expected illuminance. <br /> <br />Page 2 <br />Qbhf!279!pg!:15 <br /> <br />