▁for ▁monitoring ▁their ▁own ▁decom pression ▁status , ▁as ▁they ▁are ▁the ▁only ▁ones ▁to ▁have ▁access ▁to ▁the ▁necessary ▁information . ▁Sur face ▁supplied ▁divers ▁depth ▁and ▁el apsed ▁time ▁can ▁be ▁monitor ed ▁by ▁the ▁surface ▁team , ▁and ▁the ▁responsibility ▁for ▁keeping ▁track ▁of ▁the ▁diver ' s ▁decom pression ▁status ▁is ▁generally ▁part ▁of ▁the ▁super visor ' s ▁job . ▁ ▁The ▁super visor ▁will ▁generally ▁assess ▁decom pression ▁status ▁based ▁on ▁d ive ▁tables , ▁maximum ▁depth ▁and ▁el apsed ▁bottom ▁time ▁of ▁the ▁d ive , ▁though ▁multi - level ▁calculations ▁are ▁possible . ▁Dep th ▁is ▁measured ▁at ▁the ▁gas ▁panel ▁by ▁p neum of ath ometer , ▁which ▁can ▁be ▁done ▁at ▁any ▁time ▁without ▁dist ract ing ▁the ▁diver ▁from ▁their ▁activity . ▁The ▁instrument ▁does ▁not ▁record ▁a ▁depth ▁profile , ▁and ▁requires ▁inter mitt ent ▁action ▁by ▁the ▁panel ▁operator ▁to ▁measure ▁and ▁record ▁the ▁current ▁depth . ▁E lapsed ▁d ive ▁time ▁and ▁bottom ▁time ▁are ▁easily ▁monitor ed ▁using ▁a ▁stop watch . ▁Work sheets ▁for ▁monitoring ▁the ▁d ive ▁profile ▁are ▁available , ▁and ▁include ▁space ▁for ▁listing ▁the ▁as cent ▁profile ▁including ▁decom pression ▁stop ▁depth s , ▁time ▁of ▁arrival , ▁and ▁stop ▁time . ▁If ▁repet itive ▁div es ▁are ▁involved , ▁resid ual ▁nit ro gen ▁status ▁is ▁also ▁calculated ▁and ▁recorded , ▁and ▁used ▁to ▁determine ▁the ▁decom pression ▁schedule . ▁A ▁surface ▁supplied ▁diver ▁may ▁also ▁carry ▁a ▁bottom ▁timer ▁or ▁decom