Table 1
Spectral reflectance of untamed human skin(The results are averages for three subjects)
Wave length in angstroms | Average reflectance in percent |
---|
2400 | 3 |
2600 | 3 |
2800 | 3 |
3000 | 4 |
3200 | 11 |
3600 | 21 |
4000 | 28 |
4500 | 35 |
5000 | 42 |
5500 | 48 |
6000 | 54 |
Table 2
Intensity of the spectral lines in the radiation from a Cooper-Hewitt quartz mercury arc lamp and a Sunlight (Type S-1) lamp in an aluminum reflector. The intensities of lines are given in microwatts per square centimeter per footcandle.
| Intensity of line in microwatts per square centimeter per footcandle |
---|
|
---|
Wave length in angstroms | Cooper-Hewitt quartz mercury arc lamp | Sunlight (Type S-1) lamp in a G. E. Sunlamp |
---|
3663 | 0.566 | 0.154 |
3342 | .049 | .010 |
3132 | .349 | .056 |
3024 | .131 | .015 |
2967 | .066 | .0071 |
2925 | .019 | .0011 |
2894 | .025 | .0015 |
2804 | .039 | .0012 |
2760 | .014 | — |
2700 | .021 | — |
2675 | .038 | — |
2654 | .067 | .0004 |
2576 | .018 | — |
2537 | .074 | — |
2482 | .017 | — |
2399 | .009 | — |
2378 | .008 | — |
2345 | .005 | — |
Table 3
Footcandle-minutes exposure required for the radiation from the given source to produce a minimum perceptible erythema when the filter indicated is interposed between the source and the skin of the subject. The footcandle intensity of illumination was measured when the filter was removed.
Source of radiation | Description of filter | Footcandle-minutes to produce a minimum perceptible erythema |
---|
|
|
---|
Designation | Description | Thickness in mm | Subject 1 | Subject 2 | Subject 3 |
---|
Quartz mercury arc | none | Air | — | 260 | 320 | |
“ | A | Red purple Corex | 4.21 | 740 | 860 | |
“ | B | 1 th. microscope glass | 0.18 | 970 | 1200 | |
“ | C | Microscope slide | 0.96 | 1460 | 1750 | |
“ | D | Pyrex | 1.05 | 2050 | 2300 | |
“ | E | 2 th. microscope glass | 0.36 | 1820 | 2300 | |
“ | F | 3 th. microscope glass | 0.55 | 3180 | 3600 | |
“ | G | Pyrex | 2.99 | 17000 | 17000 | 13400 |
“ | H | Quartzlite | 2.02 | — | — | 145000 |
Type S-1 lamp | none | Air | — | | | 4160 |
“ | C | Microscope slide | 0.96 | | | 10820 |
“ | D | Pyrex | 1.05 | | | 14300 |
“ | J | Helioglass | 2.40 | | | 11650 |
“ | K | Vitaglass | 2.77 | | | 18700 |
Table 4
Relative erythemal effectiveness of radiation of various wave lengths in terms of a unit effect at λ2967.
Wave length in angstroms | Relative effectiveness a per unit of energy |
---|
3663 | 0.0000 |
3342 | 0.000 |
3132 | 0.025 |
3024 | 0.35 |
2967 | 1.00 |
2925 | 0.25 |
2894 | 0.10 |
2804 | 0.04 |
2760 | 0.05 |
2700 | 0.15 |
2675 | 0.20 |
2654 | 0.30 |
2576 | 0.70 |
2537 | 0.80 |
2482 | 0.90 |
2399 | 0.95 |
Table 5
Values for a minimum perceptible erythema.
Source of radiation | Filter Interposed | Subject No. 1 | Subject No. 2 | Subject No. 3 |
---|
|
|
|
---|
Expo. in F.C.M., E × M | Q in microwatt-seconds per sq cm | Expo. in F.C.M., E × M | Q in microwatt-seconds per sq cm | Expo. in F.C.M., E × M | Q in microwatt-seconds per sq cm |
---|
|
|
|
|
|
|
|
|
---|
Quartz | | | | | | | |
mercury | arc | none | 260 | 4000 | 320 | 4920 | | |
“ | “ | A | 740 | 4160 | 860 | 4840 | | |
“ | “ | B | 970 | 4040 | 1200 | 5000 | | |
“ | “ | C | 1460 | 4280 | 1750 | 5130 | | |
“ | “ | D | 2050 | 4610 | 2300 | 5170 | | |
“ | “ | E | 1820 | 4240 | 2300 | 5360 | | |
“ | “ | F | 3180 | 4450 | 3600 | 5040 | | |
“ | “ | G | 17000 | 4660 | 17000 | 4660 | 13400 | 3670 |
“ | “ | H | — | — | — | — | 145000 | 3580 |
Type | | | | | | | |
S-1 | lamp | none | | | | | 4160 | 3580 |
“ | “ | C | | | | | 10820 | 3650 |
“ | “ | D | | | | | 14300 | 3790 |
“ | “ | J | | | | | 11650 | 3420 |
“ | “ | K | | | | | 18700 | 3650 |
Average | | | 4305 | | 5015 | | 3620 |
Relative erythemal sensitivity | | | 100% | | 86% | | 119% |
Showing the constancy of computed values of
Q for various exposures, each of which produced a minimum perceptible erythema on untanned skin.
Table 6
Computed values of the relative erythemal effectiveness of energy of various wave lengths when various filters are interposed.
Filter interposed | Relative erythemal effect produced by energy of each spectral line, (100 Ua/∑Ua) |
---|
|
---|
λ3132 | λ3024 | λ2967 | λ2925 | λ2894 | λ2804 | All others | Total |
---|
|
---|
Quartz mercury arc as source: |
|
none | 3.4 | 17.7 | 25.7 | 1.9 | 1.0 | .6 | 49.8 | 100 |
A | 6.9 | 33.0 | 44.9 | 3.1 | 1.5 | .8 | 9.8 | 100 |
B | 9.5 | 38.2 | 45.6 | 2.7 | 1.2 | .4 | 2.4 | 100 |
C | 11.8 | 41.4 | 43.2 | 2.2 | .9 | .2 | .3 | 100 |
D | 14.7 | 46.9 | 36.4 | 1.4 | .5 | .1 | .0 | 100 |
E | 12.8 | 42.9 | 41.3 | 2.1 | .8 | .1 | .0 | 100 |
F | 16.2 | 44.1 | 37.6 | 1.6 | .5 | .0 | .0 | 100 |
G | 43.4 | 45.0 | 11.6 | .0 | .0 | .0 | .0 | 100 |
H | 100 | .0 | .0 | .0 | .0 | .0 | .0 | 100 |
|
Sunlight (Type S-1) lamp as source: |
|
none | 9.8 | 36.6 | 49.5 | 1.9 | 1.1 | .3 | .8 | 100 |
C | 16.4 | 41.5 | 40.4 | 1.1 | .5 | .1 | .0 | 100 |
D | 20.0 | 45.8 | 33.2 | .7 | .3 | .0 | .0 | 100 |
J | 17.7 | 42.2 | 38.7 | 1.0 | .4 | .0 | .0 | 100 |
K | 19.1 | 41.6 | 38.2 | .8 | .3 | .0 | .0 | 100 |