© Miller Diving All Rights Reserved Document # 030715001
7
1-A
INTRODUCTION
This manual provides general information, operation and
maintenance procedures to be used with the MILLER
400 DIVING HELMET.
The term gas shall be used as a general term throughout
this manual for compressed air or mixed gas breathing
media. No recommendations are made or implied for
an appropriate breathing media.
This manual does not attempt to teach diving techniques
or principles. It is intended as a maintenance guide for
the Miller 400 Diving Helmet to be used by properly
trained, qualified, commercial divers.
DANGER: Decompression diving always
involves the risk of decompression sickness.
Omitted decompression due to loss of gas
supply or other accidents can cause serious
injury or death. Use of a diving helmet cannot
prevent this type of injury.
WARNING: Gas systems used to supply
Miller helmets must be capable of supplying
gas to the diver at the required pressure and
flow rates as stated in the operational specifica-
tions. The use of unregulated gas sources is
extremely dangerous. The use of standard
SCUBA type regulators is unacceptable, as
there are no provisions for adjusting the inter-
mediate pressure to the diver. Only proven
systems that allow for varying the gas supply
pressure to the diver should be used for umbili-
cal diving.
1-B GENERAL DESCRIPTION OF MILLER 400
The Miller 400 Diving Helmet is designed for use with
a surface supplied life support system. Breathing gas
and two way communication are routed from the sur-
face to the diver via an umbilical, composed of a gas
supply hose, a communication wire, and a small hose
for a pneumofathometer.
The Helmet Shell, Regulator, Cams, Face and Neck
Rings are constructed of solid bronze for a lifetime of
service under constant hard use. The all metal Helmet
provides the maximum in head protection. The Helmet
moves with the diver's head without the need for an
awkward crotch strap. It is secured with an internal,
adjustable, padded neck strap. The Helmet has a free-
flow control and a heavy duty Demand Regulator. An
Oral-Nasal Mask reduces the possibility of C02 buildup;
thus the Helmet can be used economically in the de-
mand breathing mode for mixed gas diving. The Neck
Ring comes with a wet-suit-type neckseal, but can be
mated to practically any type diving suit, wet or dry.
The rugged design and quality construction of the Miller
Helmet result in a lifetime of service.
SECTION 1
GENERAL INFORMATION
