For the ultraviolet spectral region 200-315 nm, the exposure of unprotected skin or eye should not exceed the values given in the table within an 8-hour period.

Wavelength
(nm)

(mJ/cm²)*
(nm)

200

100

210

40

220

25

230

16

240

10

250

7.0

254

6.0

260

4.6

270

3.0

280

3.4

290

4.7

300

10

305

50

310

200

315

1000

For the UV-A or near ultraviolet spectral region (315 to 400 nm), exposure to the eye should not exceed 1 milliwatt per square centimeter (1.0 mW/cm²) for periods greater than 1000 seconds (approximately 16 minutes).
For exposure times less than 1000 seconds, the dose (total energy) should not exceed 1.0 J/cm².