Letters vary, I did a search and found this as a reasonable example:
Letter of Reciprocity from Chris Wade
In any case, here's a summary of what it is all about, taken from a recently replaced AAUS web page:
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What is Scientific Diving? [TR]
[TD]Scientific diving is defined by OSHA regulations (29 CFR 1910.402) as diving performed solely as a necessary part of a scientific, research, or educational activity by employees whose sole purpose for diving is to perform scientific research tasks. Scientific diving does not include tasks associated with commercial diving such as: rigging heavy objects underwater; inspection of pipelines; construction; demolition; cutting or welding; or the use of explosives.[/TD]
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[TD]According to the Code of Federal Regulations (29CFR 1910.401(2)(iv), OSHA (the Federal Occupational Safety and Health Administration has determined that an organization may be exempt from the regulations that govern commercial diving activities provided it meets the following criteria:[/TD]
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[TD]Defined as scientific diving and which is under the direction and control of a diving program containing at least the following elements:[/TD]
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[TD]1. A diving safety manual which includes at a minimum: Procedures covering all diving operations specific to the program; including procedures for emergency care, recompression and evacuation; and the criteria for diver training and certification.[/TD]
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[TD]2. Diving control (safety) board, with the majority of its members being active scientific divers, which shall at a minimum have the authority to: approve and monitor diving projects, review and revise the diving safety manual, assure compliance with the manual, certify the depths to which a diver has been trained, take disciplinary action for unsafe practices, and assure adherence to the buddy system (a diver is accompanied by and is in continuous contact with another diver in the water) for scuba diving.assure adherence to the buddy system (a diver is accompanied by and is in continuous contact with another diver in the water) for scuba diving.[/TD]
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[TD]Further guidelines for scientific diving appear in Appendix B to Subpart T:[/TD]
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[TD]1. The Diving Control Board consists of a majority of active scientific divers and has autonomous and absolute authority over the scientific diving program's operation.[/TD]
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[TD]2. The purpose of the project using scientific diving is the advancement of science; therefore, information and data resulting from the project are non-proprietary.[/TD]
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[TD]3. The tasks of a scientific diver are those of an observer and data gatherer. Construction and trouble-shooting tasks traditionally associated with commercial diving are not included within scientific diving.
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[TD]4. Scientific divers, based on the nature of their activities, must use scientific expertise in studying the underwater environment and therefore, are scientists or scientists-in-training.[/TD]
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[TD]Scientific diving programs allow research diving teams to operate under the exemption from OSHA commercial diving regulations.[/TD]
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[TD]AAUS Member Organizations help protect themselves from possible fines and civil suits by their confirmed commitment to meeting AAUS requirements and adherence to a set of standards recognized as the "standard of practice" within the scientific diving community.[/TD]
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[TD]Following a consensual set of standards enables AAUS member organizations to enjoy reciprocity when collaborating on research projects with other AAUS member organizations. This reciprocity is the product of years of experience, trust and cooperation between underwater scientists.[/TD]
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