Pressure Related Incidence Rates in Scientific Diving

In: Pollock
NW, Godfrey
Diving forAcademy
Science 2007.
Diving For Science 2007
Proceedings
Of JM,
Theeds.
American
Of Underwater Sciences
Proceedings of the American Academy of Underwater Sciences 26th Symposium.Dauphin Island, AL: AAUS; 2007.
Pressure Related Incidence Rates in Scientific Diving
Michael R. Dardeau1 and Christian M. McDonald2
1
2
Dauphin Island Sea Lab, Dauphin Island, AL 36528, USA; mdardeau@disl.org
Scripps Institute of Oceanography, La Jolla, CA 92093, USA; cmcdonald@ucsd.edu
Abstract
In 1982 the US Occupational Safety and Health Administration (OSHA) examined records of
scientific divers and, based on their finding of an exemplary safety record resulting from selfregulation, partially exempted scientific diving from the strict control placed on commercial
diving activities. A retrospective examination of recent scientific diving statistics and incident
reports was undertaken to determine if the original reasoning behind the partial exemption is
still valid. Available data going back to 1998 indicated a total injury incident rate per 100
workers comparable to the earlier OSHA study.
Introduction
Training of scientists to use SCUBA as a research tool began in the early 1950s at Scripps Institute of
Oceanography and spread to many other research programs in the ensuing decades (Hanauer, 2003).
The scope of scientific diving may range from simple observations to use of sophisticated technology
(Sommers, 1988; Hicks, 1997; Sayer, 2005) but most agree that perceived hazards may include cold
and arduous dives, task loading and time at depth limitations. Given the potential for workplace
injury, in 1977, the US Occupational Safety and Health Administration (OSHA) established
mandatory occupational safety and health standards for commercial diving operations (29 CFR Part
1910, Subpart T - Commercial Diving Regulations). Because scientific diving was not specifically
exempted from these regulations, OSHA was requested by academic organizations involved in diving
to consider an exemption, based on effective self-regulation, for diving performed for research
purposes (Butler, 1996). OSHA examined the safety records of science diving programs, conducted
hearings regarding the safety of scientific diving and concluded in 1982 that, because of an exemplary
safety record, a partial exemption was warranted (Federal Register, 1982). Scientific diving has since
grown to encompass more than 100,000 dives per year. To determine if the original reasoning behind
the partial exemption is still valid, a retrospective evaluation of scientific diving statistics from 1998
to 2005 was undertaken.
Methods
The by-laws of the American Academy of Underwater Sciences (AAUS) contain a provision
requiring organizational members to submit statistical summaries of the number of dives and divers,
the mode of diving and any incidents associated with scientific diving at intervals (typically annual)
specified by the Academy. Although incident types (hyperbaric, near drowning, etc.) are defined,
incident itself is not, leaving the diving safety officer (DSO) to determine whether or not to report.
For the past eight years, these statistics have been collected in an identical manner and stored to a
database. Review of the statistics for quality assurance purposes revealed that comparisons to the
OSHA review of scientific diving safety from 1965-1981 were possible.
111
Diving For Science 2007 Proceedings Of The American Academy Of Underwater Sciences
To evaluate scientific diving safety, OSHA calculated an annual incidence rate for pressure related
injuries in their Final Ruling (Federal Register, 1982) using a formula that is still used by the Bureau
of Labor Statistics (BLS) today:
(N/EH) x 200,000 = incidence rate per 100 full-time workers where-N = number of injuries and illnesses (including deaths) or lost workdays
EH = total hours worked by all employees during calendar year
200,000 = base for 100 full-time equivalent workers (working 40 hours/week, 50 weeks/year)
The AAUS database was employed to calculate an incidence rate for pressure related injuries for each
year from 1998 to 2005.
Results
Summaries of the annual diving activity by AAUS members from 1998-2005 are shown in Table 1.
Number of scientific dives increased from a low of 69,520 in 1999 to a peak of 124,722 in 2005.
Number of incidents ranged from 3 to 17, averaging 8.4 per year. Pressure related incidents ranged
from 2 to 13, averaging 6 per year.
Table 1. Summary of annual diving activity by AAUS organizational members from 1998-2005.
Organizational
Members Reporting
# of dives
# of divers
Total # of incidents (#
pressure related)
1998
1999
2000
2001
2002
2003
2004
2005
55
71,042
2,997
5
(3)
57
69,520
2,816
11
(8)
61
77,368
2,728
9
(8)
70
90,644
3,200
8
(5)
70
100,989
4,015
17
(13)
80
108,702
3,770
9
(5)
89
123,103
3,967
3
(2)
90
124,722
3,984
5
(5)
Each of the incidents reported between 1998 and 2005 was included in Figure 1. The only criterion
for inclusion was that a diver or a DSO thought it necessary to file an incident report. About half the
total of 67 incidents reported were thought to be some form of decompression illness. Sinus/ear
barotrauma involved mostly minor incidents, some not even requiring first aid. Environmental trauma
included bites, stings, shocks and injuries from contact with rigs or rocks. The other category
included no injury, anxiety, shallow water blackout, foreign object in the ear, hypothermia and other
infrequent occurrences. Neither the environmental trauma nor the other category was included in the
calculation of the incidence rate.
A survey of 88 organizations within the scientific diving community contracted by OSHA estimated a
diving population of 5,441 with a total of 39 pressure related incidents in the period between 1965
and 1981 (Federal Register, 1982; Sharkey and McAniff, 1984). Making various assumptions about
the number of divers and the number of incidents per year, OSHA calculated incidence rates ranging
from 0.04-1.66 per hundred divers per year (Table 2).
112
Diving For Science 2007 Proceedings Of The American Academy Of Underwater Sciences
Other
12%
Environmental
Trauma 16%
DCI
>50 %
Sinus/Ear
Barotrauma
19%
Figure 1. Types of incidents reported, n=67
(DCI, n=35; Sinus/Ear barotrauma, n=13;
Environmental trauma, n=11; Other, n=8).
Table 2. Incidence rates calculated by OSHA for scientific diving from 1965-1981 (Federal Register, 1982).
Assumptions
Calculation
All 39 incidents in one year
All incidents attributable to an early 1970s
estimate by NOAA of a diving population of 2,340 divers in
one year
All incidents averaged over 15 years using 2,340 divers
All incidents averaged over 15 years using 5,441 divers
(39/(5441x2000))x200,000
Incidence
Rate
0.7
(39/(2340x2000))x200,000
1.66
(2.6/(2340x2000))x200,000
(2.6/(5441x2000))x200,000
0.1
0.04
OSHA also noted that these values compared favorably with BLS rates from other industries.
Incidence rates for AAUS divers and BLS statistics for 1998-2005, as well as the baseline 1979
OSHA numbers, are shown in Table 3.
Table 3. Total injury incidence rates for AAUS diving and various Bureau of Labor Statistics
industry summaries. Rates from 1979 are from (Federal Register, 1982) and industry rates
from 1998-2005 are from www.bls.gov
AAUS Diving
Construction
Transportation
Ag, Forestry
and Fishing
Wholesale
Finance
Manufacturing
Mining
Service
1979
0.04-1.66
1998
0.07
1999
0.28
2000
0.29
2001
0.16
2002
0.32
2003
0.13
2004
0.05
2005
0.13
16.2
8.7
7.0
6.2
8.4
7.0
7.0
8.2
6.7
6.8
7.8
6.6
7.0
7.1
6.1
6.4
6.8
7.8
6.2
6.4
7.3
6.4
6.3
5.2
6.1
6.3
1.7
8.5
4.7
4.9
6.0
1.6
8.0
4.1
4.6
5.8
1.6
7.8
4.6
4.6
5.4
1.5
7.0
3.9
4.4
5.3
1.7
7.2
4.0
4.6
4.7
1.7
6.8
3.3
2.5
4.5
1.6
6.6
3.8
2.4
4.5
1.7
6.3
3.6
2.4
1.7
13.3
11.4
113
Diving For Science 2007 Proceedings Of The American Academy Of Underwater Sciences
Discussion
The use of scientific diving by researchers between 1998 and 2005 is higher than levels of annual
activity in the seventies estimated by OSHA. The average number of incidents reported per year is
also higher than during that period. Incidence rates among AAUS institutions between 1998 and
2005, however, remained within the 0.04-1.6 range calculated by OSHA for the late seventies. Some
of the apparent increase in both divers and incidents is, unquestionably, a function of more and better
record keeping resulting from participation in AAUS. Increased emphasis on reporting symptoms as a
result of training also probably contributed to some of the incidents reported. Many of these incidents
did not meet the OSHA criteria for inclusion (injuries and illnesses that result in days away from
work, restricted work or transfer to another job, medical treatment beyond first aid and loss of
consciousness) but were included to avoid underestimating the incidence rate.
Despite the obvious increase over time in the numbers of AAUS individuals and organizations
reporting dives, many agencies and organizations conducting scientific diving under the OSHA
partial exemption do not report to AAUS. For example, NOAA conducted 208,459 scientific dives
between 1981 and 2004 (Dinsmore and Vitch, 2005) and the Alaska Department of Fish and Game
made over 10,933 dives between 1990 and 2000 (Pritchett, 2001). Clearly, the 766,090 dives reported
to AAUS between 1998 and 2005 were not the only scientific dives being performed during that
period.
The operational definition of scientific diving adopted by OSHA implies oversight of the diving
activity. The partial exemption specifies a diving safety manual detailing operational procedures and
a diving control board to approve and monitor diving projects (Butler, 1996). The medical, training
and operational standards specified by AAUS exceed those detailed by OSHA and include record
keeping requirements, diving under the supervision of a diving safety officer, and advanced training
in rescue, CPR, first aid and oxygen administration. They distinguish scientific diving from
recreational diving and are generally considered the standard of practice for scientific diving in the
U.S. (Lang, 2003). It is clear that self-regulation and oversight of diving activity within the scientific
community has effectively maintained the incidence rate at levels considered acceptable by OSHA
when granting the partial exemption for scientific diving operations.
Acknowledgments
Thanks to all the divers and DSOs dedicated to safe scientific diving who turned in over three
quarters of a million dive records and to AAUS for allowing the use of them.
References
Butler SS. Exclusions and exemptions from OSHA's commercial diving standard. In: Lang MA,
Baldwin CC, eds. Methods and Techniques of Underwater Research. Proceedings of the American
Academy of Sciences 16th Annual Symposium, 1996: 39-44.
Dinsmore DA, Vitch ML. NOAA's diving accident management program: a review of current
capabilities and plans for improvement. In: Godfrey JM, Shumway SE, eds. Diving for Science 2005.
Proceedings of the American Academy of Sciences 24th Annual Symposium, 2005: 157-169.
Federal Register. Vol. 47, No. 228. Friday, November 26, 1982. Rules and Regulations: 1046-1050.
114
Diving For Science 2007 Proceedings Of The American Academy Of Underwater Sciences
Hanauer E. Scientific diving at Scripps. Oceanog. 2003; 16(3): 88-92.
Hicks RE. The legal scope of 'scientific diving' an analysis of the OSHA exemption. In: Maney EJ,
Ellis CH Jr, eds. Diving for Science…1997. Proceedings of the American Academy of Sciences 1997
Scientific Symposium, 1997: 87-100.
Lang MA. Scientific Diving. In: Brubakk AO, Neuman TS, eds. Bennett and Elliott's Physiology and
Medicine of Diving, 5th ed. London: W.B. Saunders Co, 2003: 56-63.
Pritchett M. Scientific diving injuries in Southeast Alaska. In: Jewett SC, ed. Coldwater Diving for
Science 2001. Proceedings of the American Academy of Sciences 21st Annual Symposium, 2001: 7577.
Sayer M. The international safety record for scientific diving. SPUMS J. 2005; 35(3): 117-119.
Sharkey PIS, McAniff JJ. Scientific diving fatalities, 1970 through 1984--a fifteen year review.
Oceans '84. Proceedings, MTS-IEEE Conference, Sept. 10-12, 1984. Washington, DC, 1984:
517-520.
Sommers LH. Scientific diver training and certification. In: Lang MA, ed. Advances in Underwater
Science…88. Proceedings of the American Academy of Sciences Eighth Annual Symposium, 1988:
165-174.
115