Transcript ISMSP_Slides.ppt

Myths and Realities of Fatigue
Circadian Technologies, Inc.
24 Hartwell Ave.
Lexington, MA 02421
Phone: 781-676-6900
Fax: 781-676-6999
Web: www.circadian.com
Copyright Circadian Technologies, Inc. 2002
IMPACT OF FATIGUE
Copyright Circadian Technologies, Inc. 2003
2004
Myth or Reality?
1.
Fixed shifts (e.g. always working the night shift) are
safer than rotating shifts.
2.
As long as its voluntary, there is no evidence that
demonstrates a clear upper limit on overtime hours.
3.
Tired haul truck drivers (or other operators) can
anticipate the onset of fatigue and take corrective
actions to avoid it?
4.
Long shifts (e.g. 12-hours or more) are less safe
than traditional 8-hour shifts
5.
Shiftworker training can measurably impact how
shiftworkers spend off-duty time and family life.
Copyright Circadian Technologies, Inc. 2004
Effects of 24/7 on Employee Fatigue

Disrupted sleep at home

Chronic sleep deprivation

Lack of awareness of extent of
sleep debt

Micro-sleep

Automatic behavior syndrome

Nodding off on the job

Reduced alertness, vigilance
and performance at work
Copyright Circadian Technologies, Inc. 2004
Reports of Nodding Off at Work
Reports of Sleepiness at Work
80
60
40
20
0
18
20
22
2
4
6
8
10
12
14
16
18
Time of Day (hrs.)
Round-the-clock workers frequently fall asleep when working the
night shifts.
Copyright Circadian Technologies, Inc. 2004
Equivalence of Fatigue Impairment to
Alcohol Impairment
0.10
0.08
0.06
Blood
Alcohol
Content
0.04
0.02
0.00
12
13
14
15
16
17
18
19
20
21
22
NUMBER OF HOURS AWAKE
23
24
Adapted from Dawson and Reid,
1997
Copyright Circadian Technologies, Inc. 2004
Effects of 24/7 on Performance
%
10
5
0
-5
Psychomot. Perf.
-10
Cancellation
Digit Summation
-15
Simulator (a)
Simulator (b)
-20
12
15
18
21
24
03
06
09
12
Time of Day
Human performance at many different tasks is most impaired
between 1 and 6 am.
Copyright Circadian Technologies, Inc. 2004
Costs In Extended Hours Operations
Productivity
1.5
Relative Efficiency
1
0.5

0
-0.5
-1
-1.5
-2
AM
10
AM
8
AM
6
AM
4
AM
2
M
id
ni
gh
t
PM
10
PM
8
PM
6
PM
4
PM
2
No
on
-2.5
Productivity
decreases at night
by 5%. This equates
to $3,300, or $79.4
billion a year
Time of Day

Study A shows
productive hours when a
person is excessively
fatigued (burnout). Study
B is after working 4
weeks of long hours.
Studies C and D are from
just 1 week of long hours.
Productive Hours per Week
60
55
Study D
50
Study C
45
Study B
40
35
Study A
30
16
40
45
50
55
60
65
70
Copyright Circadian Technologies, Inc. 2004
Business Costs: Average Tonnage by Time of
Day
12000
10000
8000
6000
4000
2000
0
16:00-0:00
1
2
3
8:00-16:00
4
5
0:00-8:00
6
7
8
0:00-8:00
8:00-16:00
16:00-0:00
Copyright Circadian Technologies, Inc. 2004
Results of Improvement in Nightshift
Performance Alone
Total Tonnage on Nightshift:
(Current)
1,971,702 tons
Total Tonnage on Nightshift:
(Minimizing 4:00am dip)
2,023,896 tons
Total Increase:
52,194 tons
=3% improvement for nightshift
=1% increase in total tonnage
ADDITIONAL 3.29 DAYS OF PRODUCTION/YEAR
Copyright Circadian Technologies, Inc. 2004
Trends In Extended Hours Operations
Health Care Costs
18

3-4 times higher rate of Obstructive Sleep Apnea

2-3 times greater rate of Gastrointestinal Disorders

2-3 times increased rate of Cardiovascular Disease

1.5-2 times more Musculoskeletal Problems

Probable increased risk of Mental Health Illnesses

2-3 times higher overall Health and Wellness Costs
Copyright Circadian Technologies, Inc. 2004
Trends In Extended Hours Operations
Accidents and Injuries


Workers comp claims 20% higher in shiftwork
operations
29% of extended hours employees fell asleep several
or more times a week while at work.
Workers' Comp and Fatigue Levels
$5,000
$4,000
$3,000
$2,000
$1,000
$0
No Fatigue
19
Low Fatigue
Moderate
Fatigue
High Fatigue
Copyright Circadian Technologies, Inc. 2004
Trends In Extended Hours Operations
Accidents and Injuries
Relative Accident Risk
1.4
1.3
Relative risk of
accidents and injuries
on different shifts
collated from five
independent studies

1.2
1.1
1
0.9
Morning
Afternoon
Night
$12,000
$8,000
$4,000
M
M
A
A
M
M
A
A
M
M
A
A
M
M
A
M
A
A
M
M
A
11
10
9
8
7
6
5
4
3
Copyright Circadian Technologies, Inc. 2004
2
1
A
t
M
gh
P
ni
id
M
M
11
M
P
M
P
M
P
10
9
8
M
P
M
P
7
6
M
P
M
P
5
4
M
P
M
P
P
3
2
oo
n
$0
1
Increased cost of
nightshift
accidents based
on insurance
company claims
data
$16,000
N

Average Cost of Accidents and Injuries
Shift
HUMAN DESIGN
SPECIFICATIONS
Copyright Circadian Technologies, Inc. 2004
Design Specs of the Human Machine
Humans were not designed for
peak performance at night
Copyright Circadian Technologies, Inc. 2004
Well Established Scientific Research on
Biological Clocks
Suprachiasmatic Nucleus (SCN)
Cerebral
Cortex
Hypothalamus
SCN
Eye
Pituitary
Optic Nerve
Brain Stem
Spinal Cord
Source: Circadian Technologies, Inc. (1981)
Copyright Circadian Technologies, Inc. 2004
Circadian Rhythm of Performance Over a
24-Hour Period
Sleep
No Sleep
98.5
Maximum
Sleepiness
Body
Core
Temperature
96.5
Thermostat
Down
11 pm
Dusk
Thermostat
Up
7 am
Dawn
Thermostat
Down
11 pm
Thermostat
Up
7 am
Dusk
Dawn
Whether we are awake or asleep, body functions continue to follow their
Circadian rhythms
Copyright Circadian Technologies, Inc. 2004
Circadian Rhythm of Human Alertness
(With Normal Quantity / Quality of Nighttime Sleep)
20
Full
Alertness
15
Alertness
Level
(MSLT)
Moderate
Alertness
10
Reduced
Alertness
5
Drowsy
0
12
15
18
21
24
03
06
09
12
Time of Day
Source: Circadian Technologies, Inc. (1993)
This is an average composite for all Circadian types. The curve can be shifted 12 hours in either direction depending on whether one is an early or late riser, etc.
Copyright Circadian Technologies, Inc. 2004
Determinants of Human Alertness:
Extended Hours Without Sleep
Time of Day
20
09
12
15
18
21
24
03
06
09
Full
Alertness
15
Alertness
Level
(MSLT)
Moderate
Alertness
10
Reduced
Alertness
5
Drowsy
0
0
5
10
15
20
25
Successive Hours of Sleep Deprivation
Source: Circadian Technologies, Inc. (1993)
Copyright Circadian Technologies, Inc. 2004
IMPACT ON SCHEDULING
Copyright Circadian Technologies, Inc. 2003
2004
Determinants of Human Alertness Consecutive Nights on Duty
20
Full
Alertness
15
Night 6
Alertness
Level
(MSLT)
Moderate
Alertness
10
Reduced
Alertness
Night 3
5
Night 1
Drowsy
Night 2
0
22
24
2
4
6
Time of Night
Source: Circadian Technologies, Inc. (1993)
Copyright Circadian Technologies, Inc. 2004
A “Free-Running” Circadian Rhythm When External
Time Cues (Zeitgebers) Are Removed
24
04
08
12
16
20
24
Day
1
2
3
4
5
6
7
8 we are isolated from time cues, our internal biological clocks run on a 25 to 25.5 hour
When
cycle. This is why they are “entrained “ or reset by the light of each day to keep our circadian
9
rhythms
on a precise 24-hour cycle. That is why it is easier to shift forward to a later time than
backward to an earlier schedule, and why forward or clockwise schedule rotations are
physiologically
less stressful to work.
etc.
Copyright Circadian Technologies, Inc. 2004
Bio-Compatible Schedules
(Physiological Design Criteria)
Bio-compatible schedules have the proper:

Rotation direction: forward

Rotation speed: slow or fixed

Shift start time: 7:00-8:00 am

Maximum schedule regularity

Minimum consecutive shifts worked

Maximum rest/recovery breaks between shift turns (48-hours
min.)

Periodic long breaks (3-4 days minimum)

Minimum sleep (night shift) transitions
Copyright Circadian Technologies, Inc. 2004
Direction of Shift Rotation Preferred by
Workers Who Have Experienced Both
80
Counterclockwise
Clockwise
18%
67%
60
40
20
0
20
40
60
80
(14% stated no preference)
Source: Circadian Technologies, Inc. (1993)
Copyright Circadian Technologies, Inc. 2004
Fatigue and Alertness Factors
8-Hour Schedules:
 Work more shifts
 Fewer rest and recovery days, less often
 More cumulative fatigue / sleep deprivation
 Shorter work day
12-Hour Schedules
 Work fewer shifts in a row (i.e., 2-4)
 More rest and recovery days, more often
 Less cumulative fatigue / sleep deprivation
 Twice as many days / weekends off
 Longer, harder work day


Combination 8 & 12-Hour Schedules
Compromise between 8 and 12-hour shifts
Copyright Circadian Technologies, Inc. 2004
How Physically Demanding Is Your Shift?
60
50.8
Percent of People
50
50
40
30
20.2
20
10
0
14.2
10.5 10.8
8.1
Very
Light
Light
7 day, 8-hr schedule
(7-2, 7-2, 7-3)
17.6
10.5 7.4
Moderate
Heavy
Very
Heavy
7 day, 12-hr schedule
(2-2, 3-2, 2-3)
Copyright Circadian Technologies, Inc. 2004
Percent of People
How Mentally Demanding Is Your Shift?
40
37.5
35
32.1
30
24
25
20.8
20
17.8
15
10
20.8
11
15.1
13.3
7.5
5
0
Not at All
Slightly
7 day, 8-hr schedule
(7-2, 7-2, 7-3)
Moderately
Demanding
Very
7 day, 12-hr schedule
(2-2, 3-2, 2-3)
Copyright Circadian Technologies, Inc. 2004
How Fatiguing Is Your Shift?
60
50.8
46.2
Percent of People
50
40
28.3
30
25
20
9.7
10
6.5
11
8.3
8.1
6.2
0
Not at All
Slightly
7 day, 8-hr schedule
(7-2, 7-2, 7-3)
Moderately
Fatiguing
Very Fatiguing
7 day, 12-hr schedule
(2-2, 3-2, 2-3)
Copyright Circadian Technologies, Inc. 2004
How Boring Is Your Shift?
50
46
45 41
40
Percent of People
35
30
27.1
25
21.3
18.2
20
16.2
15
12.2
10
4.1
6.6 7.4
5
0
Not At All
Slightly
7 day, 8-hr schedule
(7-2, 7-2, 7-3)
Moderately
Boring
Very Boring
7 day, 12-hr schedule
(2-2, 3-2, 2-3)
Copyright Circadian Technologies, Inc. 2004
Case Study A: Mining and Chemical Company
Problem:

Low Productivity

High Injury Rates

High Employee Turnover

High Medical Costs

Low Employee Morale
Copyright Circadian Technologies, Inc. 2004
Case Study A: Large Mining and Chemical
Company
Result of Shift Schedule Optimization:
87%
100%
80%
60%
28%
40%
22%
13%
20%
0%
-20%
-40%
Schedule
Satisfaction
Index
-34%
S1
Health Index
Personnel
Turnover
Benefit: $800,000 increased net profit in Year One
Worker
Productivity in
Manual
Operations
Plant
Productivity in
Process
Operations
ROI:8:1 (first year)
Copyright Circadian Technologies, Inc. 2004
IMPACT ON ACCIDENT
PREVENTION
Copyright Circadian Technologies, Inc. 2003
2004
Fatigue-Related Human Error

Inattention / lack of vigilance

Impaired judgment / lack of awareness

Carelessness / lack of precaution

Failure to follow procedures

Miscommunication / misunderstanding

Inappropriate / slow response

Microsleep / automatic behavior syndrome

Chemical impairment (drugs, alcohol, medication)
TRACK FATIGUE FACTORS IN REPORTING SYSTEMS!
Copyright Circadian Technologies, Inc. 2004
Fatigue Related Driving Accidents

6 times greater for night shift workers

2 times greater for rotating shift workers

Other high risk factors
 Working more than one job
 Getting less than 6 hours sleep
 Being awake more than 20 hours straight
 Driving between midnight and 6:00 am
Sources: AAA Study, J. Stutts, UNC 1999
Copyright Circadian Technologies, Inc. 2004
Microsleep

Short bursts of sleep waves

Seconds or minutes long

Eyelid blinking slows down

Often precedes nodding off

Loss of awareness

Fatigue/monotony induced

Serious driving and work hazard
Copyright Circadian Technologies, Inc. 2004
Microsleeps: Potholes on the Slope of
Drowsiness
ALERTNESS
Alertness Level
IMPAIRED
JUDGEMENT
TOTAL
INCAPACITY Microsleeps
(Eyes closed)
SLEEP
Hours of driving
Copyright Circadian Technologies, Inc. 2004
Microsleeps: Potholes on the Slope of
Drowsiness
ALERTNESS
Alertness Level
IMPAIRED
JUDGEMENT
TOTAL
INCAPACITY Microsleeps
(Eyes closed)
SLEEP
Hours of driving
Copyright Circadian Technologies, Inc. 2004
Automatic Behavior Syndrome

Sleeping with eyes open

Fatigue/monotony induced

Blank stare, no eye blinking

Inability to respond to changes

Deep sleep (brain) waves

Major cause of driving accidents

Loss of perception and
memory
Copyright Circadian Technologies, Inc. 2004
The Missing Factor in Optimizing 24/7
Performance
Aptitude
Productivity
Quality
Safety
Distraction
Education Load
Performance
Training
Experience
Work Load
Attentiveness
? Missing
Factor
Motivation
Source: The Twenty Four Hour Society (1993)
Copyright Circadian Technologies, Inc. 2004
Alertness:
The Missing Factor in Human Reliability
Aptitude
Productivity
Quality
Safety
Distraction
Education Load
Performance
Training
Experience
Work Load
Attentiveness
Alertness
Motivation
Source: The Twenty Four Hour Society (1993)
Copyright Circadian Technologies, Inc. 2004
Results of Performance-Based Fatigue
Management – Trucking Fleet
Histogram of Fatigue Index - mean: 45.38 std_dev: 19.84 std_err: 1.45
Accident Risk
8
7
6
Frequency in Percent
Before
$32,430 / million miles
5
4
3
2
1
0
0
5
10
15
20
25
30
35
40
45
50
55
Fatigue Index
60
65
70
75
80
85
90
95
100
Accident
Rate
2.3/mm
Accident
Avg. Cost
$14,100
Histogram of Fatigue Index - mean: 28.98 std_dev: 17.81 std_err: 1.25
8
Frequency in Percent
6
After
23%
Χ2=68.1
7
P<0.0001
5
Accident
Rate
1.7/mm
4
3
2
66%*
Accident
Avg. Cost
$4,800
1
0
0
5
10
15
20
25
30
35
40
45
50
55
Fatigue Index
60
65
70
75
Fatigue Scores
80
85
90
95
100
$8,160 / million miles
*p< 0.05
Copyright Circadian Technologies, Inc. 2004
IMPACT ON TRAINING
Copyright Circadian Technologies, Inc. 2003
2004
Managing a Shiftwork Lifestyle Training
STUDY FROM KENNECOTT COLOWYO MINE:

After training on managing a shiftwork lifestyle,
employees at a mine site:
–
–
–
–
–
2
Increased daytime sleep by 1 hour
Were less likely to stay awake for more than 18 consecutive
Were more alert
Had fewer gastrointestinal health issues
Found it easier to fulfill domestic responsibilities
Copyright Circadian Technologies, Inc. 2004
Managing Shiftwork Lifestyle Training
Employees who provided lifestyle training had:
– Lower rates of turnover compared to those that did not
– Lower rates of absenteeism
– Had cost savings associated with these lower rates of $1,892
per employee per year
Turnover/Absenteeism Rate

Turnover
Absenteeism
16%
12%
11.4%
7.6%
8%
4%
6.3%
2.9%
4.8%
4.5%
0%
No Training
Training for
Shiftworkers
Training for
Shiftworkers and
Family
Copyright Circadian Technologies, Inc. 2004
Addressing the
Extended Hours Challenge
Copyright Circadian Technologies, Inc. 2002
Myth or Reality?
1.
Fixed shifts (e.g. always working the night shift) are
safer than rotating shifts.
2.
As long as its voluntary, there is no evidence that
demonstrates a clear upper limit on overtime hours.
3.
Tired haul truck drivers (or other operators) can
anticipate the onset of fatigue and take corrective
actions to avoid it?
4.
Long shifts (e.g. 12-hours or more) are less safe
than traditional 8-hour shifts
5.
Shiftworker training can measurably impact how
shiftworkers spend off-duty time and family life.
Copyright Circadian Technologies, Inc. 2004
Elements of a Fatigue Management Program
Management and Supervisor
Education
Extended Hours Lifestyle
Training + Support
Support Policies,
Practices, and
Procedures
Bio-Scheduling
Heath and Nutrition
Programs
Pre-Employment
Screening
Fatigue Costs,
Risks &
Liabilities
Sleep Disorder
Screening and
Treatment
Optimization
Alertness Recovery
Strategies,
Goodsleep.com
Web Counseling
Staffing Levels
Fatigue Management
Systems
Environmental and
Ergonomics
Practices
Copyright Circadian Technologies, Inc. 2004
For More Information
Upcoming symposiums:

Shiftwork – Health & Safety (American Airlines)

Developing alertness monitors (Fall 2004)
Circadian Technologies, Inc.
www.shiftwork.com
dmitchell@circadian.com
Copyright Circadian Technologies, Inc. 2004