Operation Manual

109
DataTrans Plus
MORE ABOUT NITROX DIVING
WARNING: Diving with enriched nitrogen-oxygen (nitrox)
mixtures requires special knowledge of the variations imposed
upon divers, their activities, and their equipment by the in-
creased percentage of oxygen. Oceanic recommends comple-
tion of a specialized Nitrox training course by a recognized
training agency prior to diving with any enriched nitrogen-
oxygen (nitrox) mixtures.
Both central nervous system (CNS) oxygen toxicity and pulmonary oxygen
toxicity were taken into consideration when the current maximum limits (Fig.
111) for exposure to oxygen were published by NOAA in the October 1991
NOAA Diving Manual. Although CNS oxygen toxicity is considered the pri-
mary constraint for higher levels of PO2, there are circumstances in which
pulmonary oxygen toxicity can limit exposures.
CNS oxygen toxicity is not considered likely at PO2 levels below 1.30 ATA. It
is however related to diver's work level. Performing strenuous tasks could
cause the symptoms of oxygen poisoning to occur at PO2 levels lower than
they normally would appear during casual recreational diving.
The nitrox features of the DataTrans Plus are intended for use only
by recreational divers trained for nitrox diving by an instructor cer-
Fig. 111 - Oxygen
Exposure Limits
Maximum
Exposure Time
PO2
(ATA)
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
1.40
1.50
1.60
Per Dive
(Min)
720
570
450
360
300
240
210
180
150
120
45
Per 24hr
(Min)
720
570
450
360
300
270
240
210
180
180
150
R2