Code 520E-1 (Coastal Mist) reflects 78% of incident D65 light. Measured in CAM16-UCS uniform space, Behr Coastal Mist (520E-1) registers J'=91.7, a'=-9.17, and b'=-5.17 with HSL (189°, 41%, 87%) and Helmholtz-Kohlrausch perceived value 91.3 L*_HK. Because 520E-1 carries a*=-6.45 red-green and b*=-4.41 yellow-blue balance at chroma C*=7.81, Coastal Mist projects a cool cool coastal blue-grey character across drywall and millwork.
Thermal lighting shifts Behr 520E-1 predictably. Under 5000K noon daylight, Coastal Mist (520E-1) holds its native #DBE7E2 swatch; at 4000K cool office LED, 520E-1 adapts to #E2E5D9; at 3500K halogen, Coastal Mist transitions to #E8E4D2; at 3000K residential LED, 520E-1 warms to #EFE2CD; and under 2700K evening bulbs, Coastal Mist (520E-1) settles at #F4E1C9.
When cross-matching Behr Coastal Mist (520E-1, #D2E8EC), Benjamin Moore Icy Blue (2057-70, #D5EBEE, LRV 79.54%) scores ΔE2000=0.8 and CAM16=1.03, followed by Blue Angel (2058-70, ΔE=1.01). In Sherwin-Williams, Bravo Blue (SW 6784, #D3E7E9, LRV 76.72%) achieves ΔE2000=1 ahead of Aviary Blue (SW 6778, ΔE=2.53). Coordinate 520E-1 with Ultra Pure White® (PPU18-6) ceilings, Silver Chalice (640E-1) trim, Silver Strand (560E-3) hallways, and Half Sea Fog (N470-3) accents.