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Record Type: Instruction
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Directive Number: STD 1-23.2
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Standard Number: 1910.401 thru 1910.441
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Subject: 29 CFR 1910.401-1910.441, Subpart T -- Commercial Diving
Operations
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Information Date: 10/30/1978
OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
OSHA PROGRAM DIRECTIVE #100-70 (Revision #1
TO: REGIONAL ADMINISTRATORS/OSHA
THRU: DONALD E. MACKENZIE Field Coordinator
SUBJECT: 29 CFR 1910.401-1910.441, Subpart T--Commercial Diving Operations
1. Purpose
The purpose of this directive is to revise OSHA Program Directive #100-70
dated October 28, 1977. The revisions are indicated with a vertical black
line in the left-hand column. This directive provides guidelines for the
permanent occupational safety and health standard for commercial diving
operations, 29 CFR 1910.401-1910.441.
2. Documentation Affected
This directive revises and cancels OSHA Program Directive #100-70 dated
October 28, 1977.
3. Background
The permanent standard for commercial diving operations was printed
in the Federal Register, July 22, 1977. The preamble, between pages 37650
and 37668, contains information and background on the purposes and intent
of the standard. A study of this appended document should be made in conjunction
with the review of this directive, Appendix A. Supplemental information
and guidance will be provided to the field as required.
4. Action
a. CSHO Diving--CSHO's shall not perform any type of diving during the
course of an investigation or inspection.
b. CSHO inspecting.
Only those CSHO's who have received the diver familiarization training,
or are otherwise qualified by similar training or experience, shall make
diving inspections. In emergencies, when these CSHO's are not available,
a regular CSHO may be utilized until a diver-trained CSHO is available.
OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
c. Oil and gas development maps.
Area Offices that have offshore activities shall obtain Oil and Gas
Development Maps for each State having such operations. These maps are
available from the United States Department of the Interior, Geological
Survey.
d. Variance.
Normal variance procedures are in effect with respect to the diving
standard. If an employer indicates that he has a variance request pending
which has not yet been acted upon, a citation shall still be issued for
any violation, although the employer should be informed that the variance
will be taken into account in considering the proper abatement period or
proposed penalty. Questions regarding variances shall be referred through
channels to the OSHA National Office, Office of Variance Determination.
e. 29 CFR 1910.401 Scope and application.
(1) This standard applies (except as noted in the following paragraph
(2)) to all commercial diving and related support operations under the
jurisdiction of OSHA.
(2) Maritime jurisdiction.
In general, OSHA maritime jurisdiction is the same as OSHA jurisdiction
over any other industry as expressed under Section 4(a) of the Act. Since
OSHA covers all employment and places of employment within a State, the
Act's requirements apply to both inland maritime operations and any other
type of maritime employment within the 3-mile limit extending seaward from
the coastal States and from other land masses listed in Section 4(a) of
the Act, and in the case of the Great Lakes, to the international boundaries.
Section 4(a) also covers maritime workplaces beyond the 3-mile limit that
are engaged in employment operations in connection with the outer continental
shelf lands and work related to these operations.
(3) Commercial diving operations performed in connection with the following
standards:
29 CFR 1910.401-.441 - General Industry 29 CFR 1915.59 - Ship Repairing
29 CFR 1916.59 - Shipbuilding 29 CFR 1917.59 - Shipbreaking 29 CFR 1918.99
- Longshoring 29 CFR 1926.605 - Construction
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
shall be subject to Subpart T of 29 CFR 1910, Section 401-441 of this
chapter.
NOTE: The amending of 29 CFR 1928.21(b) by substituting T for S in line
4 changes that paragraph to read "Except to the extent specified in paragraph
(a) of this section, the standards contained in Subparts B through T and
Subpart Z of Part 1910 of this title do not apply to agricultural operations."
Agricultural operations include those industries listed in the Standard
Industrial Classification Manual, 1972 edition, under Division A (except
091). This division includes establishments primarily engaged in agricultural
production as follows:
SIC 01 - Crops SIC 02 - Livestock SIC 07 - Agricultural Services SIC
08 - Forestry
Therefore, any diving operations conducted by agricultural employees
engaged in employments under these SIC codes are exempt from this diving
standard. Contractors of agricultural employers who do not fall within
these SIC codes are covered by 29 CFR 1910.401-.441.
(4) When a part of 29 CFR 1910.401-.441 differs or conflicts with any
other OSHA standard, the requirements of this standard shall take precedence
when applied to diving operations. The CSHO should review 29 CFR 1910.5
for guidance before issuing a citation for a violation of a general industry
standard to a diving employer. Questions regarding this procedure shall
be referred to the OSHA National Office of Compliance Programming.
(5) Citing standards.
(a) The proper standards to cite for violations shall be determined
by the type of work for which the diving operation is required. For example:
o Repairs on vessels requiring a diver to examine damage to the hull.
Violations would be cited under 29 CFR 1915.59, with specific reference
to the section of 29 CFR 1910.401-.441 which was violated.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
o Maintenance work requiring a diver to enter a sewer line to free debris
from a strainer. Violations would be cited as appropriate, under 29 CFR
1910.401-441.
o A company is erecting an offshore oil rig that requires a diver to
perform construction work (construction work includes the actual erection,
alteration and maintenance of the rig). Violations would be cited under
29 CFR 1926.605(e), with specific reference to the section of 29 CFR 1910.401-441
which was violated.
o If the OSH is not sure which standard applies to the operation, the
OSHA shall cite both standards.
(6) This standard does not apply to diving operations under the following
conditions:
(a) Diving for instructional purposes by persons using only open-circuit
compressed air SCUBA within the no-decompression limits. In addition, it
should be noted that individuals engaged in recreational or sport diving
(generally SCUBA) for their own personal enjoyment, and not otherwise related
to their respective employments are not within the jurisdiction of this
standard.
(b) Search, rescue and related public safety diving by or under the
control of a governmental agency. Diving contractors who perform such emergency
services not under the control of the governmental agency but as an independent
contractor for private purposes do not come under this exclusion; however,
they may be covered by the provisions concerning application of the standard
in an emergency (29 CFR 1910.401 (b)).
(c) This diving standard does not apply to those specific working conditions
of diving operations over which other Federal agencies exercise statutory
authority to prescribe or enforce standards or regulations affecting occupational
safety and health. (See section 4(b)(1) of the Act.) Questions of jurisdiction
shall be referred to the OSHA National Office of Compliance Programming.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(d) This standard does not apply to diving operations when performed
for research, development and related activities in which human subjects
are involved which are covered by the standards contained in 45 CFR Part
46, Protection of Human Subjects, administered by the U.S. Department of
Health, Education and Welfare, or equivalent Federal standards. Questions
of equivalence or applicability shall be referred to the OSHA National
Office of Compliance Programming.
(7) Federal programs.
In addition, pursuant to Section 3(5) of the Act, employees of Federal
agencies of the United States Government are excluded from the jurisdiction
of the standard. Instead, such employees shall be protected in accordance
with Section 19 of the Act under which it is the responsibility of each
agency which engages in diving operations to establish and maintain an
effective and comprehensive safety and health program which is consistent
with this standard.
(8) Inspection priorities.
Diving operations which do not fall within one of the exemption categories
and which involve an employer- employee relationship are covered by 29
CFR 1910.401-.441. Inspection priorities shall be followed as stated in
the Field Operations Manual, Chapter IV, with respect to different kinds
of diving operations.
(9) 29 CFR 1910.401(b) Application in emergencies.
(a) This exclusion has been included to permit the designated person-in-charge
discretion to deviate from the requirements of the standard in situations
where death, serious harm or major environmental damage is likely to occur,
but only to the extent that such action is immediately necessary to prevent
or minimize the harm. This applies only for the duration of the emergency.
The employer is required to notify the OSHA Area Office within 48 hours
of the onset of the situation requiring such deviation. The Area Director
may request that the employer submit a written record of the notification
explaining what deviations from the standard were made and what additional
precautions were instituted to provide for the safety and health of
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the employees during the emergency. Failure of the employer to notify
the OSHA Area Office of the emergency situation within the specified time
shall be considered a violation of this provision of the standard. These
incidents shall be closely monitored to insure that this provision is not
abused. A pattern of repeated deviations shall be cause for an inspection.
(b) This emergency provision does not apply to situations involving
only economic or property damage.
(10) Federal/State jurisdiction.
(a) All States that have an approved plan have 6 months from the effective
date of this standard (October 20, 1977) to either adopt the OSHA diving
standard, pro- mulgate a diving standard as effective as the OSHA standard
or modify their present State diving standard to be as effective as the
OSHA standard. In the interim, OSHA shall enforce the diving standard wherever
diving operations are being conducted under OSHA jurisdiction.
(b) As soon as a State with an approved plan has an approved diving
standard, the State will enforce the standard under its jurisdiction.
(c) States with approved plans that have included the maritime issue
and have adopted the OSHA diving standard, or have a State diving standard
as effective as the OSHA diving standard, will have jurisdiction over diving
operations conducted in conjunction with the maritime operations from an
onshore site such as a pier, wharf, jetty, etc. The dive location (see
4.f. (4), this directive) determines the jurisdiction; however, the Federal
OSHA retains jurisdiction for diving operations conducted on the navigable
waters of the United States in these States, as well as the States that
do not have an approved plan.
f. 29 CFR 1910.402 Definitions.
(1) "ASME Code or equivalent": "equivalent" refers to equipment that
is designed, built and maintained to standards which will provide the employees
the same protection as if the equipment met the American Society of Mechanical
Engineers (ASME) Boiler and Pressure Vessel Code, Unfired Pressure Vessel,
Section VIII. The employer shall be responsible for demonstrating equivalency.
Questions of equivalency should be referred to the OSHA National Office
of Compliance Programming.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(2) "Bursting pressure": The pressure at which a pressure containment
device such as a pipe, hose, cylinder, tank, etc. would fail structurally.
29 CFR 1910.430(c)(1)(ii) requires that breathing gas supply hoses shall
have a bursting pressure at least 4 times the working pressure.
(3) "Decompression chamber": As used in this standard, this term refers
to any pressure vessel for human occupancy used to decompress divers and
to treat decompression sickness. A closed bell, if used as a decompression
chamber, shall meet the design criteria as stated in 29 CFR 1910.430(f).
(4) "Dive location": This term refers to the location from which operations
are conducted such as a vessel, barge, wharf, pier, river bank or offshore
rig and does not mean the diver's work location under the water.
(5) "Dive location reserve breathing gas": This refers to a secondary
breathing gas supply at the dive location connected and ready for use for
each dive.
(6) "Dive team": This term includes all divers and support employees
involved at the dive location in the diving operations, including the designated
person-in-charge.
(7) "Inwater stage": This term means a platform sufficient to carry
the weight of the diver and gear in and out of water.
(8) "No-decompression limits": This term applies to those depth/time
combinations where no staged decompression of the diver is required. Dives
to 35 fsw do not require decompression, regardless of bottom time. Dives
deeper than 35 fsw may require decompression. The no- decompression tables
from the U.S. Navy Manual are attached as Appendix B. The standard provides
for use of either the U.S. Navy Tables or equivalent limits which the employer
can demonstrate to be equally effective.
(9) "Standby diver": The requirement that the standby diver be at the
dive location, which by definition is a location- at the surface or on
a vessel, eliminates the pos- sibility that another diver in the water
or at another dive location would be considered a standby diver. The standby
diver does not necessarily have to be fully dressed but must be in that
degree of readiness which will allow him to render the necessary assistance
in a timely manner. A degree of readiness means to be clothed and equipped
ready to enter the water at a moment's
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
notice. The temperature at some dive locations makes it extremely uncomfortable
to a standby diver fully clothed in a wet or dry suit, so it may be necessary
to wear more comfortable dress, yet adequate enough to provide protection
when the standby diver enters the water. Such articles of gear as face
masks, air cylinders and harness can be quickly donned and need not be
worn on standby.
(10) "Working pressure": The term maximum working pressure is equivalent
to rated working pressure or that pressure level up to which it is safe
to operate as determined by construction and tests. By definition it must
not exceed 1/4 of the bursting pressure.
g. 29 CFR 1910.410 Qualifications of dive team.
(1) The level of experience or training required by the standard depends
upon the job the employees are required to do. Employee qualifications
achieved through field experience or classroom training or both may be
used to meet the requirements of the standard. For example:
(a) Most divers begin as tenders and advance to diving status after
a period of field experience and/or classroom training. A diving tender
trainee performing on-the-job training shall be utilized only under the
supervision of a qualified diver.
(b) Tenders are those members of the dive team who provide surface support
to divers at the site. A tender employed in shallow water air diving would
be required to have a basic understanding of the breathing air system,
the operating and emergency procedures and knowledge of the care and use
of equipment.
(c) A mixed-gas (system) diver is a diver who conducts underwater work
using mixed-gas techniques. A mixed-gas diver would be required to have
an advanced understanding of diving, including a working knowledge of mixed-gas
equipment such as a decompression chamber, bell and mixed-gas breathing
supply system, the operations and emergency procedures associated with
mixed-gas diving and the equipment used. In addition, he must have an understanding
of the physics and physiology of mixed-gas diving.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(d) A chamber operator would be required to have experience or training
in the carrying out of decompression procedures, knowledge of the physics
and physiology of decompression, and the operation of the decompression
equipment to which he is assigned.
(e) Each dive team member must be trained in cardio- pulmonary resuscitation
and standard first aid. The American Red Cross standard course (14 hours)
or equivalent training is specified. Employees completing this training
are issued a card attesting they have successfully completed the course.
Any first aid course acceptable to OSHA as meeting the requirement of 29
CFR 1910.151(b) and 1926.50(a) is deemed to meet the requirements of this
standard. Some other first aid courses which have been accepted by OSHA
are: American Petroleum Institute, U.S. Bureau of Mines and American College
of Orthopedic Surgeons.
(2) The following methods may be used to check individual qualifications:
(a) Field experience-
o Employment records. o Written statements from previous employers.
o Written statements from diving officers or commanding officers (military).
o Field operations records.
(b) Diving proficiency-
o Company field operations records. o Federal service operations records
(military).
(c) Technical training-
o Federal service qualification certificates. o Diving school certificates
of completion. o Company training program completion statements or equivalent
proof of competency.
(3) The phrase "known to the employer" in 29 CFR 1910.410 (b)(3) of
this part relates to the requirement that the designated person-in-charge
inquire into the employee s health prior to the task assignment, a required
aspect of pre-dive planning (29 CFR 1910.421 (f)(2)).
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(4) The designated person-in-charge can be the employer or an employee
chosen by the employer. The designated person-in-charge shall have experience
in and knowledge of all phases of the particular diving operation for which
he is responsible. The designated person-in-charge shall be at the dive
location; therefore, this team member shall not be a diver in the water
or a person at another dive location. In two-person operations, where the
diver may be more qualified than the tender, the diver can be in charge
of pre-dive and post-dive procedures and maintain overall responsibility
for the operation, but during the dive the tender must be the person-in-charge.
For instance, he must be the one authorized to terminate the dive in accordance
with 29 CFR 1910.422(i) of the standard although, if the diver himself
requested termination, there would be no discretion involved. The qualifications
of the designated person-in-charge can be checked by the same methods suggested
in the preceding paragraph (2).
h. 29 CFR 1910.411 Medical requirements.
(1) 29 CFR 1910.411(a)(1) - The employer is ultimately responsible for
determining whether affected dive team members are medically fit to perform
assigned tasks in a safe and healthful manner. However, the decision is
to be based on the best available medical opinion. The standard does not
set qualifications for physicians, although employers should be encouraged
to engage examining physicians who are familiar with and experienced in
the physical requirements and medical aspects of diving. In the absence
of physicians with knowledge of hyperbaric medicine, examinations should
be done by a physician qualified to understand the need and purpose for
the examination and who has prior experience in examining individuals who
will be exposed to strenuous work conditions and hazardous environments.
(2) 29 CFR 1910.411(a)(2) and (3) - The standard requires that any dive
team member who is, or is likely to be, exposed to hyperbaric conditions
shall be provided the medical examinations by the employer at no cost to
the employee. Therefore, it applies to any dive team member who is expected
to dive, enter a decompression chamber, or be otherwise exposed to increased
pressure. In addition to divers, this requirement shall apply, for example,
to dive team members such as tenders or designated persons-in-charge who
might reasonably be expected to enter a decompression chamber to treat,
or aid in the treatment of, a diver suffering from decompression sickness.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(3) 29 CFR 1910.411(b)(3) - The standard requires the employer to provide
a medical examination after an employee has been hospitalized for 24 hours
or more. The employer has the responsibility to inquire as to his employee's
current state of physical fitness including any recent hospitalizations.
If an employee conceals the fact of a hospitalization from the employer,
and the employer has no knowledge or reason to know of the hospitalization,
no citation shall be issued under this section.
(4) 29 CFR 1910.411(d)(1) - Information concerning an employee's diving-related
work history and medical history is' to be gathered primarily during the
examining physician's interview with the employee. Verification of such
information, as necessary, is to be obtained by the physician through established
medical channels.
(5) The tests indicated in Table I are intended to be mandatory minimum
requirements. The standard does not preclude an employer from subjecting
his employee to a more comprehensive examination but allows additional
tests to be given at the discretion of the physician based in part on likely
job duties, likely hyperbaric exposure and employee work and medical histories
(29 CFR 1910.411(a)(1)(v)). For example, Table I requires that a standard
12-lead EKG be given once at age 35 or over. This is a minimum requirement
and intended to provide a baseline tracing at a relatively early age. The
standard does not preclude the physician from making the EKG a routine
part of the diver's annual medical examination. Similarly, an examining
physician who felt that an X-ray survey would assist in detection or evaluation
of bone necrosis could have that test performed, and the findings could
be used as part of the basis for a determination of medical fitness.
(6) 29 CFR 1910.411(e) - The written reports prepared by the examining
physician are generally kept in the company office. The CSHO should make
his onsite inspection before reviewing the medical records to avoid giving
advance notice to the employer. The CSHO shall examine those records to
determine that:
(a) Medical examinations have been given as required (.411(a) and (b)).
(b) A copy of the standard and a summary of the nature and extent of
the hyperbaric conditions to which the dive team members will be exposed
were provided to the physician (.411(c)).
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(c) The employer has a physician's written report on each employee required
to be examined (.411(e)).
(d) The employer has determined the extent and nature of the employee's
fitness for the designated job (.411(f)(1)).
(e) The second has given the opportunity for second and third opinion,
if appropriate (.411(f) (2) and (3)).
(7) 29 CFR 1910.411(f) is intended to apply to all employees who will
be exposed. At this time there is a case pending in which the extent of
the employer's obligations to pay for examinations (including new hires
and free-lance divers) and to follow the procedures for a second and third
opinion under 29 CFR 1910.411 Medical requirements, is being challenged.
Until further notice is provided by OSHA, do not issue citations under
this particular standard without first consulting with the National Office.
(8) Appendix A of the standard contains a list of examples of medical
conditions which may restrict or limit employee exposure to hyperbaric
conditions. This appendix is advisory, not mandatory to the physician.
(Note: typo- graphical error in Federal Register where Appendix "B" was
printed instead of "A".)
(9) In addition to Appendix A of the standard, the following conditions
may be reasons for temporary disqualification from exposure to hyperbaric
exposure (29 CFR 1910.410(b)(3)):
(a) Acute alcoholism and/or drug intoxication.
(b) Acute gastronintestinal syndrome.
(c) Acute infections, skin, respiratory, ear, etc.
(d) Recent incident of serious decompression sickness.
i. 29 CFR 1910.420 Safe practices manual.
(1) The employer may refer to the safe practices manual as the diving
manual, employer's operational log or diving guide. The manual shall be
at the dive location and available to all team members.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(2) The safe practices manual must provide a written operational procedure
for each diving mode engaged in by the employer which contains the employer's
implementation of the standard. The CSHO shall review the manual to ascertain
if it contains safety procedures and checklists for diving operations,
assignment and responsibilities of the dive team members, equipment procedures
and checklists and emergency procedures.
j. 29 CFR 1910.421 Pre-dive procedures.
(1) The provisions of this section must be followed by the employer
for all diving modes with the designated person- in-charge responsible
for overall compliance and briefings.
(2) 29 CFR 1910.421(a) - The CSHO shall check to see that the emergency
aid list is complete and available to all dive team members.
(3) 29 CFR 1910.421(b) - The CSHO shall check to see that there is a
first aid kit at the dive location. If used in a decompression chamber
or bell, the first aid supplies shall be suitable for use under hyperbaric
conditions; e.g., they should not include bottles of liquids, mercury thermometers
or ammonia ampules.
(4) 29 CFR 1910.421(d) - Planning and assessment is essentially a "dive
plan" requirement for which the designated person-in-charge is responsible.
Most of the information required by this subsection should be found in
the safe practices manual (29 CFR 1910.420). Some information may not be
found in written form because it cannot be ascertained until the team reaches
the dive location. The CSHO shall question the team members to determine
that the employer has complied with the requirements of this subsection.
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(5) 29 CFR 1910.421(d)and (e) - Certain hazards encountered such as
weather, water temperature, current and bottom conditions can be recognized
and taken into account in the planning and execution of the operation.
When other operations being conducted in the vicinity (dredging, marine
traffic, etc.) are likely to interfere with the diving operation, the designated
person-in-charge shall plan the operation after appropriate coordination
with persons responsible for the other activities, so that any hazard to
the dive team will be eliminated or minimized. Failure to plan for such
recognizable conditions or to coordinate activities shall be a basis for
a citation.
(6) 29 CFR 1910.421(f) - The employee briefing is usually conducted
by the designated person-in-charge just prior to the divers entering the
water. It is particularly important that the designated person-in-charge
shall inquire into each dive team member's current state of physical fitness
before making individual assignments. To determine compliance the CSHO
can question dive team members and observe the operation, if one is ongoing.
(7) 29 CFR 1910.421(g) - As in the preceding subsections, compliance
with the pre-dive inspection requirement can only be determined by observations
and questioning employees. The standard makes no distinction between employer-provided
equipment and employee-provided equipment with regard to the requirement
of pre-dive inspection. While an employee can individually make such inspections,
it is the employer who is responsible for assuring compliance with all
equipment requirements of the standard.
(8) 29 CFR 1910.421(h) Warning signal.
(a) There are two distinctions in the requirements for displaying the
warning signal:
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(i) 29 CFR 1910.421(h) only requires the warning signal to be displayed
when diving from surfaces other than vessels such as wharves, piers, pilings,
jetties, fixed caissons, levees, dikes, dams, breakwater, artificial islands
(secured to the continental shelf) etc., and then only when the dive location
is capable of supporting marine traffic. Violations of this requirement
shall be cited under this section.
(ii) The requirements for displaying the warning signal when the dive
location is located on a vessel is covered by the U.S. Coast Guard Navigation
Rules, International-Inland, contained in Department of Transportation,
U.S. Coast Guard pamphlet CG-169, May 1, 1977, Rule 27, and is not enforceable
by OSHA. (See Appendix C.) If the CSHO observes violations of the warning
signal when the dive location is a vessel, no citation shall be issued.
The CSHO shall nevertheless inform the employer of the violation and recommend
abatement. The CSHO shall also note the incident on the OSHA-1 Form and
notify the nearest U.S. Coast Guard, Office of Maritime Inspection, of
all particulars of the violations.
(b) The warning signal is a rigid replica of the international code
Flag "A", at least one meter in height (depicted below).
As long as the flag is displayed to achieve virtual all around visibility,
the requirement for rigidity shall have been met.
k. 29 CFR 1910.422 Procedures during dive.
(1) This requirement covers the time the diver enters the water until
the diver leaves the water.
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(2) 29 CFR 1910.422(c) - The requirement for two-way voice communication
shall be checked. Pull signals do not meet the requirements except in the
SCUBA mode.
(3) 29 CFR 1910.422(d) - The CSHO shall check that the proper decompression
and treatment tables are at the dive location. (4) 29 CFR 1910.422(e) -
The dive profile information may be recorded by whatever means and whatever
form the employer wishes provided the information is maintained accurately
and completely.
(5) 29 CFR 1910.422(f) - Hand-held power tools and equipment.
(a) The standard does not require a hand-held power tool to have a pressure
sensitive manual control switch. However, when electrically powered hand-held
tools are used underwater and the source of power is supplied from the
dive location, bell or habitat, the hand-held power tool shall not be supplied
with power from the dive location until requested by the diver.
(b) In addition to the requirements of 29 CFR 1910.422(f)(1) and (2),
all hand-held electrical power tools and equipment must be acceptable within
the meaning of the National Electrical Code Section 110-2 (adopted by 29
CFR 1910.309(b)).
NEC Section 110-2 states: The conductors and equipment required or permitted
by this code shall be acceptable only when approved. (Approved means acceptable
to the authority enforcing this code, NEC Section 100). Clarification of
"approved" is given in 29 CFR 1910.308(d)(1) which states in part: "The
authority enforcing the code under subpart S is the Assistant Secretary
for Occupational Safety and Health." Further, "acceptable" is defined under
29 CFR 1910.308(d)(2) which states: An installation or equipment is acceptable
to the Assistant Secretary. of Labor, and approved within the meaning of
this subpart S:
o If it is accepted, or certified, or listed, or labeled, or otherwise
determined to be a safe by a nationally recognized testing laboratory,
such as, but not limited to, Underwriters Laboratory, Inc. and Factory
Mutual Engineering Corp.; or
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o With respect to an installation or equipment of a kind which no nationally
recognized testing laboratory accepts, certifies, lists, labels, or determines
to be safe, if it is inspected or tested by another Federal agency, or
by a State, municipal, or other local authority responsible for enforcing
occupational safety provisions of the National Electrical Code, and found
in compliance with the provisions of the National Electrical Code as applied
in 29 CFR 1910.309; or
o With respect to custom-made equipment or related installations which
are designed, fabricated for, and intended for use by a particular customer,
if it is determined to be safe for its intended use by its manufacturer
on the basis of test data which the employer keeps and makes available
for inspection to the Assistant Secretary and her authorized representatives.
(6) 29 CFR 1910.422(g) - Personnel designated to operate electric cutting
and welding equipment used in diving operations shall have experience or
training in the safe use of underwater cutting and welding equipment (29
CFR 1910.410(a)(2)(i)). There shall be a positive acting disconnect switch
in the electrical circuit, located so that the tender on the intercommunication
system can oversee and operate the switch at all times that the diver is
in the water (29 CFR 1910.422(g)(1)(i)). The disconnect switch must be
in the open position except when the diver is actually cutting or welding
(29 CFR 1910.422(9) (1)(ii)). The employer must provide insulated gloves
for the diver's protection (29 CFR 1910.422(g)(4)). The CSHO shall check
to see that the welding machine's frame is properly grounded and that cables,
electrode holders and connections are insulated (29 CFR 1910.422(g)(2)
and (3)).
(7) This standard does not place any restriction on the use of AC current
or rectified AC current arc welding.
(8) 29 CFR 1910.422(g)(5) - "Closed compartments" means any space which
is enclosed by bulkheads and overheads (walls and ceilings) such as inside
large diameter pipes, or any other space which by its size and closed nature
can hold or contain a flammable gas or vapor. The compartments, structures
and pipes shall be freed of all flammable gases and vapors prior to hot
work by ventilating, flooding or purging with an inert gas. Venting alone
is
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
not sufficient unless it results in freeing the compartments, structures
or pipes from flammable gases. Closed compartments, structures and pipes
already under flow, as in hot tapping operations, by necessity meet the
requirement for being flooded.
(9) 29 CFR 1910.422(h) - Explosive charges are used to perform some
types of work underwater, including demolition, sheet cutting, cable cutting
and the making of holes. Explosives suitable for underwater work include
primacord, various gelatins, plastic blocks and some liquids. The requirements
of this subsection are addressed to the need for proper handling, storage
and use of explosives as covered by 29 CFR 1910.109 and 1926.912 and to
the hazard of premature detonation while the diver is still in the water.
The standard requires the diver to be out of the water when detonating
the explosive or testing the electrical continuity of the explosive circuits.
Only personnel who are properly trained or experienced shall handle explosives
(29 CFR 1910.410(a)(1) and (2)(i)).
(10) 29 CFR 1910.422(i) - Termination of dive. This sub- section applies
to all diving modes. The designated person-in-charge is responsible for
determining when a dive shall be terminated. Termination means the ending
of the working interval of a dive; it may still be necessary to complete
the decompression procedures.
l. 29 CFR 1910.423 Post-dive procedures.
(1) 29 CFR 1910.423(c) Recompression capability.
(a) The 6-month delayed effective date as stated in 29 CFR 1910.441
has now expired. Therefore, whenever the standard requires the use of decompression
chambers or bells, all employers shall be subject to meeting these requirements.
(b) Whenever the standard requires a decompression chamber, there must
be a member of the dive team available at the dive site trained in its
use (1910.423(c)(5)).
(c) 29 CFR 191".0423(c)(3)(i) - The expression "dual-lock" is meant
to include multilock components, each of which is large enough to transfer
personnel and supplies into and out of the main compartment while it is
pressurized. A medical lock is a relatively small
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
dual-lock compartment that permits equipment be passed into and out
of a decompression therefore would not meet the intent of 10.423(c)(3)(i).
(d) To be used as a recompression facility (i.e., in lieu of a chamber),
a diving bell must meet all the criteria listed in 29 CFR 1910. 423(c)(3)
and 1910.423(c)(1). Chambers used for dives in the depth range of 0-300
fsw shall have a pressure capability of at least 165 fsw (6 ATA). Chambers
used for dives in the depth range of 300 fsw and deeper shall have a pressure
capability equal to the maximum depth of the dive. (The CSHO shall check
the dive plan and tables for maximum depth of the dive).
(2) 29 CFR 1910.423(d) - The standard does not require a standard form
or that the dive records for each individual diver be kept on a separate
sheet. Where there is more than one diver working, the information required
may be kept for all divers on one record, although there should be separate
entries for each different diver exposure or decompression table used.
(3) The information required shall also be recorded on the OSHA-200 Form
(Log of Occupational Injuries and Illnesses). Each employer shall maintain
in each establishment a log of recordable occupational injuries and illnesses.
The key word is "recordable." The intent of this section is to request
documentation of a recordable illness, including an incident of decompression
sickness, when the initial symptoms were such manifestations as skin itch,
slight joint cramps, and slight numbness of the extremities. Although seemingly
innocuous, such symptoms or indications are recognized and suspect as mild
forms of decompression chamber. Such occurrences and treatments shall be
recorded similarly to any other case of injury or illness.
(4) 29 CFR 1910.423(e) - This section requires the employer to investigate
and evaluate each incident of decompression sickness, to take appropriate
corrective action, and to prepare a written evaluation assessing the incident
within 45 days. The corrective action may include an adjustment of the
dive procedures, reassessment of the decompression tables or a reexamination
of the particular dive involved. A check of the dive records should reveal
whether an incident took place requiring an investigation, corrective action
and a written evaluation.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
m. 29 CFR 1910.424-427 Specific diving operations.
(1) The requirements of sections 29 CFR 1910.424 through 1910.427 are
in addition to any other applicable requirement in Subpart T.
(2) 29 CFR 1910.424(c)(3), 1910.425(c)(2) and 1910.426(c)(3) - There
shall be a diver at the point of entry of an enclosed or physically confining
space when there is a significant entanglement hazard. Depending on the
situation, a point of entry may be under water or on the surface (e.g.,
a marine railway). An enclosed or physically confining space in this context
includes any diving situation where there is a significant possibility
of entrapment or line entanglement, or the diver is required to make one
or more sharp turns around wrecks, pilings, or has to enter closed compartments,
caves or pipes, etc.
n. 29 CFR 1910.424 SCUBA diving.
(1) The limits for SCUBA diving are more restrictive than for surface-supplied
air diving or mixed-gas diving. (See chart on following page.)
(2) 29 CFR 1910.242(b)(3) - Three basic types of currents affect diving
operations: river or major ocean currents; currents produced by the ebb
and flow of the tides (which may add or subtract from any existing current);
and underwater, or rip-current, caused by the rush of water returning from
waves breaking along a shoreline. The CSHO shall determine that the employer
has ascertained the strength of the local currents at the dive site from
Tide and Current Tables, Coast and Geodetic Survey Charts, Coast Pilot
Publications or other sources. A SCUBA diver is handicapped when swimming
against a current greater than one knot and the standard prohibits such
activity unless line-tended. A SCUBA diver may, however, swim downstream
with a current if means are provided to pick him up.
(3) 29 CFR 1910.424(c)(1) - The standard requires a standby diver for
all operations. He shall be available at the dive location equipped and
ready to go to the assistance of the diver in the water. A buddy-diver
in the water does not satisfy the requirement of a standby diver. A tender
can be the standby diver if the diver is line-tended and visible from the
surface.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
COMPARISON OF REQUIREMENTS ACCORDING TO THE THREE DIVING MODES __________________________________________________________________________
SYMBOLS: = less than knot=1 nautical mile fsw=feet of sea water
= greater than no-D=No decompression limits NA=Not applicable __________________________________________________________________________
REQUIREMENTS | SCUBA | SURFACE=SUPPLIED AIR | MIXED GAS _______________|_________________|_______________________|________________
LIMITS | 130 fsw | 190 fsw 1F | NA | 1 knot/no line | 30 minutes | | Enclosed
no line| 220 fsw 1F | | | 30 minutes | _______________|_________________|_______________________|________________
|Either line tend-|Continually tended all | 1 tender diver Tender |ed from
surface |depths. | 1 diver in bell |or another diver |1-tender/diver when
| as tender |in continual vis-| 100 fsw or no-D | |ual contact | | _______________|_________________|_______________________|________________
| | | Standby | yes | fsw no-D | yes | | | _______________|_________________|_______________________|________________
Diver |Yes(manual re- | 100 fsw no-D | 100 fsw no-D carried |reserve or
inde- | No direct ascent (ex- |no direct ascent Reserve |pendent reserve
| cept heavy gear and |(except heavy |cylinder.) | no space.) |gear and
no | | |space.) _______________|_________________|_______________________|________________
Diver | NA | 100 fsw no-D | Yes Location | | | _______________|_________________|_______________________|________________
In Water | NA | Heavy Gear | Heavy gear. Stage | | | 100 fsw no-D | | |(if
no bell.) _______________|_________________|_______________________|________________
| | | Chamber | 100 fsw no-D | 100 fsw no-D | Yes _______________|_________________|_______________________|________________
| |120 min. (except heavy |Open or Closed: Bell | NA |gear and confined
| 220fsw 120 min. | |space.) |(except heavy | | |gear and | | |confined
space). | | |Closed: 300 fsw | | |(except confined | | |space). _______________|_________________|_______________________|________________
| | | Communications | Emergency |Emergency Assistance, |Emergency Asst.
| Assistance |between diver and lo- |between diver & | |cation,diver
and bell, |location,diver & | |bell and location |bell, and bell &
| | |location. _______________|_________________|_______________________|________________
Miscellaneous |Diver at point of|Diver at point of entry|Diver at point
|entry. Require |Heavy gear,extra hose. |of entry. Heavy |person in charge.|Require
person in |gear,extra hose. | |charge. |require person | | |in charge.
_______________|_________________|_______________________|________________
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(4) In addition to any conditions listed in 29 CFR 1910. 422(i) for
termination of the working interval of the dive, the standard requires
termination of the dive in instances where the designated person-in-charge
is also the standby diver and he is required to enter the water to assist
a diver, thereby creating a situation where there would not be a designated
Person-in-charge remaining at the dive location (29 CFR 1910.410(c)(11).
o. 29 CFR 1910.425 Surface-supplied air diving.
(1) When required (see chart), decompression chambers and bells when
used as a recompression facility shall meet the criteria as stated in 29
CFR 1910. 423(c) and 29 CFR 1910.430(f) (decompression chamber only).
(2) In addition to any condition listed in 29 CFR 1910.422(i) for termination
of the working interval of the dive, the standard requires termination
of the dive whenever the required standby diver, entering the water to
assist a diver, creates a situation where there would not be a designated
person-in-charge (29 CFR 1910.410(c)(1)), or a tender remaining at the
dive location (29 CFR 1910. 425(c)(1)). The standby diver can be either
the person-in-charge or the tender or both for dives less than 100 fsw.
(3) Below 100 fsw or outside the no-decompression limits, each diver
must have his own tender. In addition, a standby diver must be available
at the dive location. The standard does not require a standby tender for
the standby diver.
(4) 29 CFR 1910.425(c)(4)(iv) - The reserve breathing gas supply required
at the dive location for dives deeper than 100 fsw or outside the no-decompression
limits shall be "on line" ready for use and its source shall be independent
of the primary breathing gas supply. The dive location breathing gas supply
shall be of sufficient quantity, pressure and quality to allow each diver
to complete the planned decompression interval.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
p. 29 CFR 1910.426 Mixed-gas diving.
(1) When required (see chart), decompress1on chambers and bells when
used as a recompression facility must meet the criteria as stated in 29
CFR 1910. 423(c) and 29 CFR 1910.430(f) (decompression chambers only).
(2) In addition to any condition listed in 29 CFR 1910. 422(i) for termination
of the working interval of the dive, the standard requires termination
of the dive whenever the required standby diver, entering the water to
assist a diver, creates a situation where there would not be a designated
person-in-charge (29 CFR 1910.410(c)(l)) or a tender remaining at the dive
location (29 CFR 1910.426(c)(1)).
(3) 29 CFR 1910.426(c)(1) and (2) - Because a mixed-gas diver must have
his own tender at all times, as well as a standby diver available to assist
him in the water, the tender cannot be used as a standby diver unless there
is someone qualified and available to take his place as the tender. The
standard does not require a separate standby diver for each diver in the
water.
(4) 29 CFR 1910.426(c)(5) - The reserve gas supply required at the dive
location shall be "on line" ready for use and its source shall be independent
of the primary breathing gas supply. The dive location reserve breathing
gas supply shall be in sufficient quantity, Pressure and quality (mix)
to allow each diver to complete the planned decompression interval.
q. 29 CFR 1910.427 Liveboating.
(1) Liveboating is conducted in either the surface-supplied air or mixed-gas
mode, and is subject to the requirement of the particular mode used and
to the applicable general requirements. In addition, it is also subject
to those requirements which are specific to liveboating.
(2) 29 CFR 1910.427(d)(2)* - When inspecting a live-boating operation,
the CSHO shall check to see that there is a device designed to minimize
the possibility of the diver's hose becoming entangled in the vessel's
propeller. Such a device may be a propeller shroud, or a weighted fairlead
hose system
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
or an air tugger with a heavy weight. The use of a tender to prevent
hose entanglement without some mechanical support is not sufficient to
satisfy this requirement. If a floating hose is used, the hose shall be
checked carefully to make sure that the requirements for breathing gas
supply hoses are met (29 CFR 1910.430(c)).
(3) In addition to any condition listed under 29 CFR 1910.422(i) for
termination of the working interval of a dive, the standard requires termination
of the dive whenever the standby diver, entering the water to assist a
diver, creates a situation where there would not be a designated person-in-charge
(29 CFR 1910.410(c)(1)) or a tender remaining at the dive location (29
CFR 1910.425(c)(1) or 1910.426(c)(1)).
(4) 29 CFR 1910.427(d)(4)* - A standby diver is required for all liveboating
operations.
*NOTE: Typographical error in Federal Register - 29 CFR 1910.427(c)
was mistakenly printed as .427(d). The CSHO should nevertheless cite to
1910.427(d) until a correction is made in the Federal Register.
r. 29 CFR 1910.430 Equipment.
(1) 29 CFR 1910.430(a)(2) - The CSHO shall check to see that the employer
has recorded the information required by this section. The information
may reveal whether or not the equipment is in need of maintenance, testing
or replacement, in that it does not currently meet the substantive requirements
of 29 CFR 1910.430. These records (logs or tags) must be kept by the employer
until replaced by a subsequent up-to-date record or until the equipment
is withdrawn from service.
(2) 29 CFR 1910.430(b) - Air compressor systems shall be inspected to
see that they have a volume tank, check valve, pressure gauge, relief valve,
drain valve and an air intake which is located away from the exhaust or
other contaminants.
(3) 29 CFR 1910.430(b)(4) - The employer is responsible for checking
the output of the air compressor every 6 months to ensure that the respirable
air of the diver does not contain contaminants in excess of the concentrations
listed in 29 CFR 1910.430(b)(3) or a
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
noxious or pronounced odor. The CSHO shall interview appropriate employees
and examine the records indicating results of such tests. The CSHO shall
also check to see that the air sample was taken as near as possible to
where the air enters the distribution system to the diver. If required,
the CSHO or Industrial Hygienist should obtain a sample for later checking
ashore or, when possible, test for contaminants onsite.
(4) 29 CFR 1910.430(c) - Breathing gas supply hoses.
(a) It is the intent of 29 CFR 1910.430(c)(1)(i) to require the hoses
to meet the pressure level re- quirement of the part of the system to which
it is connected. Therefore, a hose connected in the part of the system
on the low pressure or downstream side of a regulating valve must meet
only the pressure level of that part of the system. For instance, the hose
does not need to have a working pressure equal to the pressure of the bottles
of gas in the bank but only equal to that of the system downstream of the
regula- tor. The working pressure rating will usually be found on each
length on a decal with the manufacturer's name.
(b) 29 CFR 1910.430(c)(1)(ii) - See definition of bursting pressure,
paragraph 4.f.(2) of this directive.
(c) 29 CFR 1910.430(c)(2)(i) - Installation of cadmium-plated or other
corrosion resistant Plated fittings are acceptable and meets the requirements
of "corrosion resistant" to the extent that the plating is intact during
the diving operations. However, when the plating becomes badly worn and
the parent metal becomes pitted, the fitting shall be replaced.
(5) 29 CFR 1910.430(c)(3)(ii) - This requirement for kink resistant
hoses in umbilicals is applicable to the breathing gas hose, hot water
hose or other control hoses that carry air or liquids. The breathing gas
hose in the umbilical must also meet the applicable requirements of 29
CFR 1910.430(c).
(6) 29 CFR 1910.430(c)(3)(iii) - The maximum allowable working pressure
of the breathing gas hose can be calculated by subtracting the maximum
depth of the supply source (surface or bell in p.s.i.) from the
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
maximum depth of the dive for which it will be used (in p.s.i.) and
adding 100 p.s.i.. The determining factor is the pressure differential
between the supply source and the diver.
(7) 29 CFR 1910.430(f)(1) - The meaning of ASME or equiva- lent code
is covered under 4.f. of this directive.
(8) 29 CFR 1910.430(f)(3)(i) - Appropriate means to maintain the oxygen
level below 25 percent may include a ventilation system or an overboard
dump system. An overboard dump system is a system designed to exhaust the
expired gases from the 02 system (used for respiratory purposes inside
a decompression chamber), to prevent a build-up of 02 inside the Decompression
Chamber above 25 percent by volume of the ambient atmosphere. (9) 29 CFR
1910.430(g)(4) - The requirement for a time- keeping device applies to
all diving modes including SCUBA.
(10) 29 CFR 1910.430(h)(2) - The intent of this "helmet and mask" provision
is to assure that air is supplied to the diver at a rate sufficient to
meet the breathing requirements of the diver and to dilute or flush from
the masks and helmets the diver's expelled air. The specifications are
based on recommendations of the National Institute of Occupational Safety
and Health (NIOSH) and the U.S. Coast Guard. This section is intended to
guide the design and selection of masks and helmets, not to serve as a
basis for routine operational tests or field verification. Although this
section does not require the employer to perform any particular test on
helmets and masks, it does require that the appropriate ventilation rate
be maintained throughout operational use. Citations shall be issued under
this section only after a check with the OSHA National Office of Compliance
Programming.
(11) 29 CFR 1910.430(i)(2) - The intent of this section on "oxygen cleaning"
is to make sure that certain equipment must be cleaned internally of flammable
materials before initially being placed into oxygen service. Similarly,
whenever new or replacement components are added, they shall also be cleaned
before being connected into the system.
s. 29 CFR 1910.440 Recordkeeping requirements.
(1) 29 CFR 1910.440(a)(1) - The 48-hour time period for reporting fatality
and hospitalization (five or more) cases is the maximum time allowed by
29 CFR 1904.8. Employers should be encouraged to report such cases as soon
as possible after the occurrence.
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(2) 29 CFR 1910.440(a)(2) - The CSHO shall examine the employer's record
of diving-related injuries and illnesses which result in the hospitalization
for 24 hours or more of any dive team member. These incidents do not have
to be reported (unless five or more hospitalizations are involved) but
the record must be made available to OSHA on request. Frequency of injuries
and illnesses may be an indication of improper planning or dive procedures.
(3) 29 CFR 1910.440(b)(1) - This section gives the CSHO the authority
to inspect and copy any record required by this standard.
(4) 29 CFR 1910.440(b)(2) - In order to protect employee Privacy, it
is intended that authorized representatives of employees obtain the specific
consent of employees involved prior to receiving individual medical records.
OSHA's policy in regards to the medical records is to prevent any misuse
of such information that may be available through any requirement of this
recordkeeping standard.
(5) 29 CFR 1910.440(b)(4) - This requirement is to provide a mechanism
for extended retention of certain records that are important for long-range
epidemiological studies. The transfer of these records to NIOSH after the
5-year retention period is intended to relieve the employer of the burden
of keeping the records beyond the 5-year period. However, if the employer
has an adequate storage and retains the records beyond the 5-year period,
no citation shall be issued, provided the records are available for inspection
and copying by either OSHA or NIOSH. Such action by the employer shall
be considered de minimis.
t. Relationship with the other Federal agencies/transportation to site.
(1) In general, OSHA Area Directors should coordinate inspection activities
with local U.S. Coast Guard counterparts in a manner which seeks both to
minimize the duplication of agency resources and maximize the protection
of affected workers.
(2) Consistent with considerations of operational efficiency and the
safety of agency personnel, transportation necessary to the conduct of
off-shore inspections shall be secured in accordance with the following
priority:
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OSHA INSTRUCTION STD 1-23.2 OCTOBER 30, 1978
(a) Appropriate Federal agency, on an "as available" basis.
(b) Private contractor.
(c) Employer supplied.
(3) Consistent with existing rules and regulations, accident investigation
reports, statistical data, and other pertinent enforcement related information
should be freely exchanged between other agencies at the local level.
5. Effective Date
This directive is effective immediately and will remain in effect until
canceled or superseded.
Bruce Hillenbrand Acting Director, Federal Compliance and State Programs
Attachments
DISTRIBUTION: A-1 E-1 B-2 HEW-1 C-1 NIOSH Regional Program Directors-1
D-4 & 5 NACOSH-1 Training Institute-4
(Originator:OCCM)
-27- Appendix A
Appendix A consists of the preamble to the Commercial Diving Operations
Standard con- tained in the Federal Register dated Friday, July 22, 1977,
Part 111, Vol. 42, No. 141 between pages 37650 and 37668.
-28-
FOR TABLE 1-11 NO DECOMPRESSION LIMITS AND REPETITIVE GROUP DESIGNATION
TABLE FOR NO DECOMPRESSION AIR DIVES SEE PRINTED COPY.
-29-
FOR TABLE 1-11 NO-DECOMPRESSION LIMITS AND REPETITIVE GROUP DESIGNATION
TABLE FOR NO-DECOMPRESSION AIR DIVES SEE PRINTED COPY.
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