6
over against the first stage.
When diving in cold water (below 45
0
F, or 7
0
C), you must have received training and
certification in the techniques of cold water diving from a recognized training agency.
The Neptune II Nira is designed and intended for use only with clean, compressed
atmospheric air. DO NOT use this equipment with any other gas or enriched oxygen mixture
above 23% oxygen. Failure to observe this warning may result in serious injury or death due to fire
or explosion.
Section 1
USE OF THE NEPTUNE
II
1.1 PRODUCT APPLICATION
The NEPTUNE II is designed for diving with SCUBA equipment. There are 2 ports to connect a
regulator 2nd stage and 1 port for an underwater communication unit (diver to diver or diver to
surface).
1.2 PRODUCT CHARACTERISTICS
All the thermoplastic materials used to produce the NEPTUNE II have superior technical
characteristics and optimum resistance to mechanical impact, chemical agents and aging. The
primary component of the NEPTUNE II is the visor made of highly transparent (> 90%) poly-
carbonate with high mechanical resistance. A poly-siloxane resin coating increases abrasion
resistance and protects against chemical agents like oil and gasoline. The visor is attached to a
double-contoured face seal. It is sustained by an non-flexable six-strap harness which is directly
connected to the visor. Both the face seal and the inner mask are made of soft silicone for
maximum comfort, even at low temperatures and during prolonged use. The air circulation valves
are also made of silicone for maximum resistance against deterioration with age.
The air from the regulator, whether attached in the front or side position, enters the inner mask
through the two one way valves and ventilates the visor glass to avoid fogging.
The oral nasal cups also separate the fresh air from the exhaled air limiting the percentage of
inhaled CO2. Exhaled air passes through the lower adjustable exhalation valve, which allows
bubbles to escape laterally and not interfere with the visor.
The volume of air in the mask and the distance of the second stage regulator from the divers
mouth cause increased loss of pressure and regulator breathing resistance.
Changes in regulator performance can also be caused by the different positions
assumed during a dive;
the use of a regulator with flow adjustment is recommended.
When descending the adjustment knob must always turned on to get the proper air flow.
Do not turn off the adjustment knob during descending.
1.3 DIVE PREPARATION
The NEPTUNE II is tested with the Ocean Reef regulators Dynamic 6600, ENTERPRISE TR94
Polar and the integrated 2nd stage NIRA with TR94Polar 1st stage. The manufacturer
does not guarantee the performances of the NEPTUNE II using other regulators.
The NEPTUNE II has both frontal and lateral regulator attachments and is designed to
allow the connection of two second stages.
It is recommended that the diver carry,