6. Glossary

Densité Optique (DO); optical density

For a given length, it is the decimal logarithm of the inverse of the transmission factor :

DO = log(1/T)

where T is the ratio of transmitted energy flux to incident flux.

Exposure Limit Value (ELV); Valeur Limite d'Exposition (VLE)

Maximum eye or skin exposure value at which no deleterious biological effects are expected, irreversible. (synonyms: LE and VLEP).