Practica_Accidentes - Universidad de Granada

Investigación de accidentes
desde la ergonomía
cognitiva
Prácticas de Ergonomía 2014
Profesor Ángel Correa Torres
Universidad de Granada
Colisión de trenes Metrolink 111 y UnionPacific LOF65-12
25 muertos, 138 heridos, >12.000.000$
Chatsworth, California. 12 Septiembre, 2008
Fuente: Informe del accidente NTSB/RAR-10/01.
National Transportation Safety Board (PB2010-91630).
It was premature to blame the engineer, "there
could always be a technical malfunction where ...
there was a green light both ways."
Miembro del consejo de Metrolink
Informe de un accidente
1.
Información de los hechos
2.
Análisis
3.
Conclusiones
4.
Recomendaciones
CP: Control Point
¿FACTORES POSIBLES?
1. Información de los hechos
Factual Information .......................................................................................................................1
Accident Synopsis ............................................................................................................................1 Accident Narrative ...........................................................................................................................1 Emergency Response .......................................................................................................................8 Command, Organization, and Resources ..................................................................................9 Extrication Operations ............................................................................................................10 Injuries ...........................................................................................................................................11 Damage ..........................................................................................................................................11 Personnel Information ....................................................................................................................12 Metrolink Train 111 ................................................................................................................12 Union Pacific Leesdale Local .................................................................................................13 Person A ..................................................................................................................................14 Train and Mechanical Information ................................................................................................15 Metrolink Train 111 ................................................................................................................15 Leesdale Local ........................................................................................................................18 Wreckage .......................................................................................................................................19 Metrolink Train 111 ................................................................................................................19 UP Leesdale Local ..................................................................................................................22 Topanga Switch ......................................................................................................................22 Meteorological Information ...........................................................................................................22 Train and Mechanical Information
Metrolink Train 111
- Inspections and Maintenance: ok
- Event Recorders: A recorder was undamaged in the
accident, and investigators downloaded its data on scene.
Meteorological Information
- Weather conditions: at 3:51 p.m. visibility of 4 miles.
- Signal Information: Downloaded data from Digicon event
logs at the Metrolink dispatching center and signal event
recorders in the field indicate that, at the time of the
accident, the westbound signal at CP Topanga
was displaying a red aspect (stop indication).
Centros de Gestión del Tráfico
Ferroviario
Centros de Regulación y Control: Los CRC integran todos los sistemas tecnológicos que
intervienen en la regulación del tráfico ferroviario exclusivamente de alta velocidad.
Imagen: CRC de Antequera para el seguimiento de la línea Córdoba-Málaga
Sight-Distance Tests of the Signal
About 4:30 p.m., investigators boarded the cab of a
three-car Metrolink train while it was positioned at its
typical spot alongside the Chatsworth station platform.
The Metrolink engineer who participated in the test
stated that he could see the signal at Topanga,
but he noted that he knew where to look through
experience.
Medical and Toxicological Information
- Type 2 diabetes, treated with multiple medications.
- High blood pressure (benazepril).
- Diagnosed HIV positive (anti-retroviral medications), no reported to the
railroad medical department.
- On 2007, an “Authorization to Work with Medication(s) and Without Work
Restrictions” completed by the engineer’s endocrinologist noted that the
engineer was “fit for duty and can complete all duties of the
position”.
- In December 2004, records of a physician visit noted that the engineer “may
have sleep apnea, but he has no way of knowing. He thinks he does snore a lot
….”
Post-Accident Toxicological Testing
- Metrolink engineer no alcohol or drugs.
NATIONAL TRANSPORTATION SAFETY BOARD
METHODOLOGY FOR INVESTIGATING OPERATOR
FATIGUE IN A TRANSPORTATION ACCIDENT
Initial Screening Questions:
- Does the operator’s 72-hour history suggest little sleep, or
less sleep than usual?
- Did the accident occur during times of reduced alertness
(such as 0300 to 0500)?
- Had the operator been awake for a long time at the time of
the accident?
- Does the evidence suggest that the accident was a result of
inaction or inattention on the part of the operator?
05:54
Engineer Sanchez begins his 11-hour split shift.
06:44
Sanchez begins his morning run.
08:53
Sanchez finishes his morning run after exchanging 45 text
messages while en route.
09:26
Sanchez finishes the first part of his shift and goes off duty.
14:00
Sanchez returns to work after reportedly taking a two-hour nap.
15:03
Sanchez begins his afternoon run.
15:30
Sanchez uses his cell phone to order a roast beef sandwich from a
restaurant in Moorpark.
Personnel Information
Metrolink Train 111 Engineer.
He had, on two occasions, received oral
counseling about his cell phone use while
on duty
Person A:
- Teenager and a self-described “rail fan.”
- Person A said that he would occasionally send
text messages to the engineer while he
was on duty and that the engineer would respond
“when he got a chance.”
Metrolink Engineer’s Use of a Wireless Device
El tren de mercancías avisa que va a llegar a
Topanga, donde se pone en rojo el semaforo
Intercambio de mensajes de texto mientras el tren se
salta el semáforo
The General Code of Operating Rules
Rule 1.10 Games, Reading, or Electronic Devices
Unless permitted by the railroad, employees on duty must not use electronic
devices not related to their duties.
Metrolink Timetable No. 5 Additions and revisions to General Code of
Operating Rules dated July 8, 2008, adds to Rule 1.10:
[Unless permitted by the railroad, employees on duty must not:]
• Use cellular telephones when operating the controls of
moving equipment except in emergencies.
2. Análisis
Exclusion
- Work/rest histories of all crew members: no fatigue.
- Obesity: increased risk for obstructive sleep apnea
(OSA), which can result in fatigue and significant cognitive
and psychomotor deficits.
- During last 2 minutes the engineer was
engaged in text messaging, manipulating the
throttle, sounding the train horn and bell, and
making brake adjustments, with no period of
inactivity that might have suggested a lack of
alertness due to fatigue or lack of sleep.
- When train 111 departed, the engineer had opportunities
to observe and respond to the signal at CP Topanga.
- His train was moving during this time, so the signal would
have been coming more clearly into his view as he
approached it.
- He did not call out this signal over the radio,
and he did not respond appropriately to the
stop indication.
- He was not fully attentive to his primary task of
operating his train safely.
- He did manipulate the train controls during this time,
but these manipulations involved long-practiced and
ingrained tasks that he could carry out with
little conscious effort and without being particularly
focused on his work.
- During at least part of the time that he should have been
observing the signal at CP Topanga, the engineer was
likely reading an incoming text message,
formulating a response, and entering that
response into his wireless device.
Ceguera inatencional
3. Conclusiones
The following were neither causal nor contributory to this
accident:
- weather, fatigue, the engineer’s medical conditions or
treatments, training and experience of crewmembers,
operation of Union Pacific Leesdale Local, alcohol or illegal
drug use by operating crewmembers, and condition of the
track or rolling stock.
- The signal and traffic control systems worked as designed
on the day of the collision
3. Conclusiones
- El intercambio de mensajes con el móvil comprometió la
habilidad del maquinista para detectar y responder
apropiadamente a la señal de stop.
- El maquinista era consciente de que violaba las normas de
seguridad pero seguía haciéndolo.
- Las condiciones de privacidad de las cabinas impiden un
control apropiado de si los maquinistas cumplen con la
normativa.
4. Recomendaciones
- Implantación de un sistema de grabación de audio y de
video dentro de la cabina para vigilar que la tripulación
cumple las normas de seguridad.
- Implantación de un “positive train control system”:
automáticamente toma el control de un tren si la tripulación
no respeta alguna señal.