Filling Procedure. Allow a short burst of air to clean out the filling port prior to attaching the filling yoke,
Turn the reserve lever to the "DOWN POSITION" to allow air to flow past the reserve mechanism, Attach
filling yoke, open ON/OFF knob and fill cylinders. After filling. turn ON/OFF knob closed and remove the
filling yoke. Turn levers to "UP POSITION" for storage.
General. A twin harness consists of two stainless steel "figure eight" bands, center bolted. Extruded rub-
ber strips assure a non-slip contact against cylinder walls,
Harness webbing is threaded through slots in the bands and held firmly in position by the clamping
of bands against the cylinders. Two inch nylon webbing is used for comfort on the shoulder pads. Ad-
justable waist, chest. shoulder. and crotch straps are provided; straps are equipped with quick re-
lease "D" rings. All harness webbing and hardware is box stitched with heavy nylon thread.
The harness assembly remains on the cylinders at all times. Reserve valve pull rod tabs are provided
on each band.
Use. Support the cylinders at a comfortable height from the deck (or have a buddy hold them up) and slide
first one arm then the other into the shoulder harness loops as if putting on a coat. Secure the chest strap
with a quick release loop. Now stand up and adjust the shoulder strap D-rings so the cylinder hangs at
a comfortable height on your back.
Bring the crotch strap forward and insert the waist strap through the crotch strap loop end. Crotch
strap length should be adjusted for snug, not tight, fit. Form a quick-release loop in the waist strap
"D" ring and another in one of the shoulder strap "D" rings. The shoulder straps can be used to support
the weight of the cylinders when they are being taken off the back.
Push the reserve lever upward prior to diving to set reserve. When using a crotch strap, the weight
belt must be put on last, over the top of the crotch strap, so the weight belt may be dropped in an
Avoid sudden pressurization of gauges. Turn on air slowly with the gauge dial fac-
ing downward. Once the gauge IS under full pressure, swivel to read.
Tank Pressure Gauge Assembly (Regulator Attachable). This gauge provides the diver with a rapid read-
out of air pressure during operation. It is attached to the first stage regulator at the port identified by the
LETTERS "HP" (see fig. 4-1). It should be worn in a comfortable manner and be easy to read when
brought to position by the divers left hand.
Gauge, Tank Pressure. This gauge IS used in checking tank air pressure (out of water) and is required
during tank filling operations. Its use in this operation is described in Chapter 5, FM 20-11-l) "Military
Section II. OPERATIONAL READINESS
The minimum equipment which must be worn by divers during open circuit diving operations are listed in Section II
and FM 20-11-1 "Military Diving Manual". The standard accessories consisting of face mask, life preserver, knife,
sheath. weight belt, swim fins. wrist watch and depth gage are identified in Supply Catalog SC 4220-97-CL-E11 .
OPERATIONAL CHECKS AND SERVICES.
Prior to placing the equipment into operation the diver wiII conduct pre-dive checks and services listed in Table 2-1
Upon completion of diving operations "Post -dive checks and Services." Table 2-2 will be completed.