9. Glossary

Working levels months (WLM)

Unit used to measure radon exposure in mines for a 170-hour working month. 1 WLM = 3.54 mJ h m–3.

Effective dose E (Sv)

This is a biological dose widely used in radiation protection. It takes into account the sensitivity of the tissues affected (tissue weighting WT) and the nature of the radiation (radiation weighting WR).

Alpha potential energy (EAP)

For short-lived radon-222 progeny, corresponds to the sum of the energies of the alpha particles emitted when all the short-lived radon-222 progeny have decayed.

Balance factor (F)

It reflects the relative importance of the progeny in relation to their parent. It is the ratio between the actual PAE of a mixture of radon progeny and the relative...