Interior Lighting for Designers

TABLE 14

SAMPLE COEFFICIENT OF UTILIZATION TABLE

Note:the coefficient of utilization values in this table are based on relative photometry which assumes a ballast

factor of 1.0. Any calculations prepared from these data should include an appropriate ballast factor.

INTERIOR LIGHTING FOR DESIGNERS

Coefficients of Utilization—Zonal Cavity MethodEffective Floor Cavity Reflectance 0.20

RC 80 70 50 30 10 0

RW 70 50 30 10 70 50 30 10 50 30 10 50 30 10 50 30 10 0

0 868686 86 84848484 808080 777777 747474 72

1 828078 76 80787675 757472 727170 706968 67

2 777471 68 76727067 706866 686664 666463 62

3 736864 61 71676360 656259 636158 615958 56

4 696358 55 67625855 605754 595653 575553 51

5 645853 49 63575249 555249 545148 535048 47

6 605348 44 59524844 514744 504644 494643 42

7 564843 39 55484339 474239 464239 454139 38

8 524439 35 51433835 423835 423835 413734 33

9 483934 31 47393431 383431 383331 373330 29

10 44 36 30 27 43 35 30 27 35 30 27 34 30 27 33 29 27 26