better
to
lock
up
the
back
brakes
than
the
front
I
have
right-
-
and
the
other
driver
is
going
the
wrong
way
(~30
mph),
no
time
to
use
radio
2
min
5
min
1-
wks
1- days
7
sec
1
sec
1
sec
10
min
gets
loaded
for
last
load
before
lunch downshifts
to
10
mph
ready
to
turn
right slams
foot
brake
(natural
reaction,
never
uses)
calls
leadman
on
personal
cell
phone
for confidentiality
does
something
like
a
“pre-
”
inspection,
takes
pictures
of
truck
and
scene
4
hrs
10
sec
3-
sec
safely
stops
truck
writes
up incident
card
makes
plan
with
group
feels
safe
puts
truck
in
park,
hazard
lights
on
goes
to
lunch
room
and
clocks
out
feels
comfortable
with
this
truck
everything
flies forward
glasses
come
off
feels
truck
sliding
on
dirt
road,
sees
silo
on
left
and
sandpile
on
right
sees
unexpected
right
headlight
oncoming
downhill
from
left
sees
other
driver
“zoom”
past
on
his
phone,
window
down,
looking
the
other
direction
blind
right
turn
coming
up
need
to
slow
down
in
“thin
area”
(one
lane),
can’go
downhill
loaded
ready
for turn
need
to
release
brakes,
especially
foot
brake
asap
shouldn’be
using
foot
brake,
hand
valve
is
lifeline
don’turn
wheel
go
to
management,
don’
confront
co-
(learned
in
safety
training)
“ I
think
the
other
driver
was
probably
trying
to
“beat
me”
so
he
could
rush
off
to
lunch...thought
he
would
miss
collision
with
me
because
I
was
slow
and
loaded.”
performs
“pre-
trip”
inspection
Spoke
to upper managemen
t
about incident Decision
11
Asked leadman
if
he
followed
up
with
other
driver Decision
10
Call supervisor instead
of confronting
other
driver Decision
9
Continue
on
to
the
dump Decision
8
Take pictures
of
truck
and scene Decision
7
Decision
6 Release
hand
brake
&
foot brake
Almost collides
with oncoming
haul
truck
Decision
5
Pull
hand
brake
and
keep
wheel straight
Decision
4
Use
foot brake
Decision
3
Slow
down
to
take
right
turn
Decision
2 Group agrees
to take clockwise route through beanfield
Decision
1
Truck
is ready
for operation,
drive
to
pit
to
meet
work
group Night
shift
at
surface
SSG
mine.
The
participant
haul
truck
operator
(“CDM-
is
working
with
one
other
haul
truck
operator
and
a
leadman.
CDM-’
usual
truck
(70
ton)
is
in
for
repairs
and
is
driving
a
different
truck
(50
ton).
It
is
dark
and
foggy
with
the
only
lighting
coming
from
headlights
and
moonlight.
CDM-
estimates
visibility
at
30%
-
40%.
Radio
control
only.
Group
meets
to
make
and
agree
to
a
plan
before
beginning
each
shift.
Unless
explicitly
discussed,
both
drivers
are
to
follow
specified
route
all
shift.
Timeline
Elements
Decision
Event
Action
Sensory
cue/ perception
Cognition
Information CDM-
has
been
a
heavy
equipment
operator
for
15
years
(e.g.,
loaders
and
a
variety
of
trucks).
Haul
truck
experience
includes
1
year
at
prior
mine
and
2.5
years
at
current
mine.
When
asked,
the
supervisor
said
he’
talk
to
the
other
driver
but
CDM-
never
heard
anything
else
about
it.
CDM-
notes
the
company
doesn’“single
outdrivers
”
so
it
remains
unknown
whether
the
other
driver
faced
any
consequences.
Figure
1.
Example
of
a
decision
chart:
an
event
timeline
that
incorporates
perceptions,
cognitions,
actions,
and
decisions
identified
by
participant
as
well
as
additional
contextual
information
4