Specifications

MILSTD-1472E
5.4.1.8 Prevention of accidental actuation,
5.4.1.8,1 Location and dcsi~n, Controls shall be designed and located so that they are not
susceptible to being moved amidentally, partietdarly critical controls whose inadvertent operation
might cause equipment damage, personnel injury, or system performance degradation.
5.4.1 .8,2 Internal controls. Internal or hidden controls should be protected, because it is
usually not obvious that such controls have been disturbed and it may be difficult and time consuming
to locate and readjust them.
5.4.1 .8.3 Rapid omration.
Any methodof protecting a controlfrom inadvertent operation shall
not preclude operation within the time rapired.
5.4.1 .8.4 Methods. If a control must be protected from accidental actuation, one or mote of the
following methods, as applicable, shall be used:
a.
b.
c.
d.
e.
f.
/3”
Locate
and orient the control so that the operator is not likely to strike or move it accidentally
in the normal sequence of control movements.
Recess, shield, or otherwise surround the control by physical barriers. The control shall be
entirely contained within the recess or barrier envelope.
Cover or guard the control. Safety
or lock wire shall not be used.
Interlock the control so that extra movement (e.g., a side movement out of a detent position or
a pull-to-engage clutch) or the prior operation of 2 related or locking control is required.
Provide the control with movement resistance (e.g., viscous or coulomb friction, spnng-
Ioading, or inertia) so that definite or sustained effort is required for actuation.
Lmckthe controi to prevent its quickly passing through a position when strict sequential
activation is necessary (i.e., the control is moved only to the next position, then delayed).
Design the control for operation by rotary action.
5.4.1 .8.5 Dead man controls. Dead man controls, which will result in system shut-down to a
non-ctitical operating state when force or input is remove~ shall be utiMA whemvcr opemtor
incapacity can produce a critical system condition.
5.4.1 .8.6 Foot-operated controls.
5.4.1 .8.6.1 Use. Foot-operated controls maybe used when
a. control opmtion requires either greater force than the upper body can provide or force close to
an upper body fatigue threshold,
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moment that an additional control action is required,
c. spcciflc foot-operated controls have been so well established that the operator expects such
opc.mtkg functions
tc IIC pcrfcmcd using fnnt rwmh (r g , nirrrnftnv-lr!w~m!w ~r!n!s
automotive clutch,
britke. and xceterator pedals), or
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