Unique elements for the UVMRP/erythemal data entity.

Irradiance in W/m2 over the erythemal spectrum (300-400nm), weighted with the Mc Kinlay and Diffey  (1987) action spectrum.

See the UVMRP_README for headers common to all entities.

Column headers:
•	Erythemal 

QC codes (0 OR semi-colon delimited list):
•	nb = no bias correction
•	bg = electronic noise in the signal due to aging of the components or interference from adjacent instrumentation