Schroth Racing All models - Competition Instructions - Manual (Page 13)

Optimal performance of your racing harness requires proper
installation and proper use. Heed and obey the following instructions
with respect to racing harness geometry and routing:
• Bracket installation and operation
• Wearing the racing harness
• Adjusting the racing harness
L AP B ELT R OUTING ( APPLIES TO ALL RESTRAINT TYPES )
To achieve optimal restraining function – lap belt strap length must be
as short as possible. This requirement can be achieved by following the
instructions set forth below:
¾
Distance between the lap belt anchor points should not be greater
than the width of occupant’s pelvis or the outer width of the
occupant’s bucket seat. The distance of approximately 400 mm [16”]
is recommended. If there are choices of several anchor points
choose those that come the closest to these recommendations.
¾ Lap belt straps must be routed over the pelvic bone to stay firmly and
tightly in the crest between the pelvic bone and the upper thigh.
¾ Lap belt downward angle should be approximately 60° measured
from the horizontal, passing through the occupant’s hip joint. This is
the suggested angle for upright seating [15-20° backrest declination].
A higher backrest declination, e.g. 30° – 40°, as is common in open
wheel race cars, requires a belt angle of 70° – 80°.
¾ Make sure there are no sharp edges [seat structure, seat mounts,
chassis] that may tear or cut the lap belt webbing.
S HOULDER B ELT R OUTING ( APPLIES TO ALL RESTRAINT TYPES )
¾ Shoulder belts must run from the shoulders horizontally or down, at no
more than a 20° angle.
¾ In cases where the shoulder belts must be routed down to the chassis
floor, support by a roll cage bar or harness guide at the appropriate
height is essential to establish the horizontal shoulder strap routing off
the shoulder/HANS
® . Most racing seats are not designed and tested
to carry shoulder belt crash loads from downward installation. Severe
injury or death could result. A 45° downward shoulder belt installation
is possible with seats that SCHROTH has positively tested to take a
load measured during a 50 kph [31 mph] and 28 G impact with a 75
kg (175 lb) dummy. Refer to the list of SCHROTH approved racing
seats in section “About Seats”. WARNING: 45° downward shoulder
belt installation is not recommended with HANS
® .
¾ For the best restraint of the occupant’s upper torso, ideal anchor
points should not be further back than 200 mm [8”] from back of
user’s seat.
¾ In the event that the anchor points are further towards the rear of the
vehicle [e.g. using a roll cage bar for wrap around attachment] the
distance between the strap anchor points will narrow or even cross
over as described in following graphs and tables.
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