Ocean Technology Systems Spectrum, Owner'S Manual

Page: 14 / 24

14
Donning and Adjustment
Proper donning of the Spectrum FFM is crucial when using diving
equipment. An improperly adjusted mask will result in jaw fatigue,
increased air consumption, leaking, and an overall poor fit.
First and foremost the Spectrum FFM must be fitted to the chin; the rest of
the mask will seal to the face where it lays.
With the mask straps fully extended, move
the communications (either the Buddy
Phone or EM assembly) as far as possible
to the rear of the straps to prevent them
from binding against the buckles. Open
the lower straps and bring the mask and
harness over the head (Figure 14). Ensure
the harness is straight and the center is low
on the back of the head.
Hold the Spectrum FFM to the face with one
hand and tighten the lower (jaw) straps one
at a time, switching hands to accommodate
tightening the other. Pull the straps toward
the back of the head, not out to the side.
Tighten the straps evenly to prevent pulling the back of the head harness
off center. Do not overtighten.
Next, tighten the temple straps evenly. If
necessary, tighten the top strap just enough
to pull the top of the skirt tighten to the
forehead. DO NOT OVERTIGHTEN THE
TOP STRAP! This can result in jaw fatigue
after just a short period of time. Wiggle the
Spectrum FFM on the face to ensure the
mask is in proper position and centered
with no stress points. Evenly tighten the
straps (Figure 15) to the desired tension,
again not overtightening the straps. The
mask should be comfortable on the face.
Overtightening the top strap will cause
the center of the head harness to sit high on the back of the head. This
results in the mask being pulled up on the face and not back , as desired.
Consequences of this error include possible leaking, jaw fatigue, and an
uncomfortable dive. If there is the need to tighten the top strap, pull down
on the back of the head harness to ensure its proper positioning low on the
back of the head. Tighten the top strap as necessary.
Figure 14: Open Lower Straps
and Bring Over Head
Figure 15: Tighten
Straps Evenly