Commercial Diving

Effective November 1, 1986

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These regulations may be cited as the Commercial Diving Regulations.

DEFINITIONS

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In these regulations
"ambient pressure"

means the external pressure on the body of a diver;

"atmospheric diving system"

means a diving system in which the ambient pressure for the person using the system is maintained at normal atmospheric pressure;

"bail-out system"

means an independent breathing medium supply carried by the diver of sufficient quantity to return the diver to the surface, bell, or emergency supply in the event of a malfunction of the primary breathing medium supply;

"bottom time"

means the total elapsed time, measured in minutes, from the time a descending diver leaves the surface to the time the diver begins final ascent (for this calculation, time shall be rounded to the next whole minute);

"breathing medium"

means mixed gas or respirable air or both;

"closed bell"

has the same meaning as submersible compression chamber;

"commercial diving"

means any diving activity involving a worker and employer as defined by the Act;

"decompression schedule or table"

means the procedure that a diver follows during the ascent from depth in order to minimize the risk of decompression sickness;

"decompression sickness"

means a disease caused by the formation of gas bubbles in the blood or body tissues as a result of pressure reduction;

"deep diving"

means any mode of diving to depths greater than 55 m (180 ft.);

"diver"

means a diver who is engaged in commercial diving;

"diver’s tender"

means a worker who is knowledgeable in the diving apparatus being used, the diving operation in progress, emergency diving procedures and diving signals between diver and tender;

"diving bell"

means a surface-tethered structure that can accommodate divers under water;

"diving plant and equipment"

means all parts of the life-support system of a diver;

"diving supervisor"

means a competent person who has responsibility for a diving operation;

"dressed-in"

means that the diver is fully equipped to dive and is ready to enter the water with all life-support and communications equipment tested and at hand but not necessarily with the helmet, face plate, or face mask in place;

"hyperbaric chamber"

means a pressure vessel and associated equipment designed for the purpose of subjecting humans to greater than normal atmospheric pressure;

"lifeline"

means synthetic rope 19 mm (5/8 in.) in diameter having a breaking strength of 2700 kg (6000 lbs) that meets the requirements of Canadian Standards Association Standard 259.2-1980;

"life-support hose bundle (umbilical)"

means a composite hose and cable or separate cables extending from the surface to the diver or to the pressure vessel of occupancy of the diver that supplies breathing medium, power, heat, or communication as required;

"liveboating"

means the support of a surface-supplied diver from a vessel under way;

"lock-out submersible"

means a self-propelled, submersible compression chamber from which a diving operation can be carried out and which has a separate one atmosphere chamber from which the submersible is piloted;

"mixed gas"

means a respirable breathing mixture, other than respirable air;

"no decompression limit"

means that, in accordance with the diving decompression table in use for the depth and duration of the dive, no decompression stop is required during the ascent;

"open bell"

means a diving bell designed so as not to be operated with a differential pressure across the hull;

"qualified medical practitioner"

means a licensed medical doctor knowledgeable in the physics, physiology and medical aspects of diving;

"saturation diving"

means a technique of diving in which the decompression schedule used allows a bottom time of unlimited duration;

"scuba"

means self-contained underwater breathing apparatus;

"stage"

means a cage, basket, or platform in which a diver may be lowered to or raised from a work site;

"stand-by diver"

means a diver who is dressed-in and who is trained and equipped to operate at the depths and in the circumstances in which the submerged diver is operating;

"submersible compression chamber (closed bell)"

means a hyperbaric chamber designed for transporting divers at normal atmospheric pressure or at an elevated pressure from the surface to the underwater work site and vice versa;

"surface-supply diving"

means a diving technique in which the diver is supplied with a breathing medium by way of an umbilical;

"therapeutic recompression"

means treatment of a diver, usually in a hyperbaric chamber, in accordance with acceptable tables and practices;

"umbilical"

has the same meaning as life-support hose bundle;

"unusual incident"

means any incident that has potential for injury and that results from or affects the diving operation, regardless of whether the incident occurs prior to, during, or after the diving operation.

GENERAL REQUIREMENTS

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(1) A diver must hold a valid certificate of physical fitness in Form A issued by the board; any restrictions or other limiting conditions noted on the certificate shall be observed.

(2) The medical examination and certification shall be made annually, or more frequently when required by the qualified medical practitioner.

(3) A report on the completed medical examination shall be submitted by the examining qualified medical practitioner to: The Workers' Safety and Compensation Board, Box 2703, Whitehorse, Yukon Y1A 2C6

(4) The diving supervisor shall ensure that the diver is

(a) physically fit before making any dive,

(b) medically re-examined if there is any doubt about the physical fitness of the diver, or

(c) capable of functioning safely and effectively under water.

(5) A medical alert tag or bracelet to indicate the possibility of decompression sickness or other diving illness shall be worn by the diver for at least 24 hours after completing a dive; the medical alert tag shall be registered with a recognized agency that has facilities for 24-hour service and is acceptable to the board.

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(1) The diver's employer shall ensure the diver has successfully completed training in the theory and use of the diving apparatus that he will be required to use.

(2) Every diver, diver's tender, and diving supervisor shall be:

(a) certified by an agency acceptable to the board as qualified in:

i. cardio pulmonary resuscitation, and

ii. survival first aid.

(b) trained in the treatment of drowning victims.

(3) Agencies for certification under subsection (2) include but are not limited to, the Canadian Heart Foundation, the Canadian Red Cross, and the St. John Ambulance Association.

DIVING RECORDS

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(1) The diver shall maintain a personal log book that records the information required by subsection (2) and (3) and retain it for a period of 2 years; the diver's current log book shall be available on the dive site for inspection by an officer.

(2) The log book shall show in chronological order the following information:

(a) the entry for each dive witnessed and signed by the diving supervisor,

(b) all entries for medical recompression or other exposure to hyperbaric environment witnessed and signed by the attending physician or diving supervisor, and

(c) all entries for medical examinations supported by certificates signed by a qualified medical practitioner in accordance with section 3.

(3) The log book shall record the following information for each dive

(a) type of diving apparatus,

(b) breathing medium used,

(c) time left surface,

(d) time left bottom,

(e) bottom time,

(f) time reached surface,

(g) total time of dive,

(h) maximum depth attained,

(i) surface interval, if a repetitive dive was undertaken,

(j) decompression table and schedule used,

(k) date,

(l) name of employer,

(m) remarks, unusual incidents, etc.

(4) For dives originating from a diving bell, habitat, or other submerged base, the diver's log book shall record

(a) the depth at such a base,

(b) the time of leaving the base,

(c) the greatest depth attained, and

(d) the time of return to that base.

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(1) A daily record of each dive containing the information required in subsection 5(3) shall be kept by the diving supervisor and filed with the diver's employer; such record shall be separate from the log owned and maintained by the diver.

(2) The diver's employer shall retain the daily record for a minimum period of 2 years.

DIVING INSTRUCTIONS AND SUPERVISION

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The employer shall have written Safe Driving Instructions that:

(a) specify safe procedures and health requirements for all the types of diving required,

(b) incorporate all the requirements of these regulations and include emergency, evacuation, and rescue procedures,

(c) are issued to all workers involved in diving operations,

(d) are readily available on each dive site, and

(e) are made available, upon request, to an officer.

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A general plan of a diving operation shall be discussed in detail and accepted by the diving supervisor, the divers, and the on-site representatives of the employer or owner.

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(1) Each diving operation shall be conducted under a diving supervisor whose duties shall include

(a) planning the dive,

(b) briefing the crew, and

(c) ensuring that all necessary equipment is provided and in good operating condition.

(2) The diving supervisor shall remain on the dive site at all times that diving operations are in progress.

(3) The diving supervisor shall delegate all supervisory responsibilities to another competent supervisor if required to enter the water.

GENERAL SAFETY MEASURES

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Diving activities shall not be carried out from a diving station located above the water unless suitable means are provided to

(a) transport the diver through the air-water interface, and

(b) recover an injured or unconscious diver.

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A dressed-in stand-by diver shall

(a) be on the dive site at all times when a diver is in the water,

(b) be positioned so as to be capable of rendering immediate assistance,

(c) only enter the water in event of an emergency.

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(1) When diving activity is being conducted, the following warning devices shall be displayed:

(a) marker buoys shall be used to display warning devices (flags, lights, lamps, or flares) to define the limits of the diving area, and boats other than those connected with the diving activity shall be kept clear, or

(b) in navigable waters the recognized diver's flag shall be flown;

(2) Diving warning devices shall be displayed only during diving activities.

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(1) The diving supervisor shall ensure that no diving operation is conducted when a barge, scow or vessel enters, moves or relocates in the diving area if such movement could affect the safety of the diver.

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(1) When divers are operating from floating equipment a suitable power boat shall be available for immediate use.

GENERAL DIVING HAZARDS

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Immediately before each dive the diving supervisor shall ensure that the diver fully understand the hazards likely to be encountered in the diving operation.

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(1) When a diver approaches a location which may be made hazardous by operation of machinery or equipment, the latter shall be

(a) secured against inadvertent movement before the diver enters the water, and

(b) locked-out in accordance with the General Safety Regulations, Section 76.

(2) A diver required to approach a controllable intake or exhaust shall

(a) be provided with means to clearly identify the intake or exhaust, and

(b) not approach the intake or exhaust until the flow is stopped.

(3) Flow shall not be re-established until the diver

(a) leaves the water, or

(b) is verified to be clear of the hazardous area by the diving supervisor.

(4) A diver who approaches an uncontrollable intake of exhaust shall wear a lifeline while in the hazardous area.

(5) A second diving team, with independent equipment and capable of effecting rescue, shall be available on immediate call at the diving operation when there is

(a) exceptional risk of entrapment of a diver,

(b) special hazard to a diver, or

(c) exceptional risk of loss of the diver's essential life support systems.

NOTIFICATION OF DIVING ACCIDENT OR INCIDENT AND EMERGENCY PROCEDURES

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(1) In accordance with the Act, an officer shall be notified immediately if the following occurs during any diving operation:

(a) death,

(b) injury,

(c) convulsions, or serious impairment of consciousness during or after a dive,

(d) decompression sickness requiring treatment,

(e) air embolism,

(f) any serious mishap, even though the diver escapes injury, or

(g) any incident prior to, during, or after the diving operation which renders equipment or procedures suspect.

(2) In the event of any diving accident or incident an officer may take temporary possession of and investigate all equipment related to the diving operation.

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The diving supervisor shall ensure that an up-to-date list of the location and telephone number of all facilities containing a recompression chamber, the hospital nearest the diving operation and available emergency assistance is maintained at the dive site.

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In the event of equipment malfunction or symptom of distress, the diver shall, if possible, notify his tender and diving partner by an appropriate signal and terminate the dive.

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(1) No diving operation shall be permitted unless the following are ready and available for immediate use:

(a) a reserve and an emergency supply of the breathing medium sufficient to bring the diver and stand-by diver to the surface with appropriate decompression stops, and

(b) an additional 72 hour reserve supply of the appropriate breathing medium when a submersible chamber is being used.

(2) The purity standards for breathing mediums shall be in accordance with CSA 275.2-M1982, "Occupational Safety Code for Diving Operations".

(3) The diving supervisor shall ensure that written authorization has been obtained from the board prior to the use of mixed gas. The written authorization shall be kept on the dive site and be available for inspection.

(4) No diver shall breathe pure oxygen while submerged.

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(1) Diving operations, repetitive dives, and treatment of divers, shall be carried out in accordance with tables and procedures acceptable to the board.

(2) Tables and procedures acceptable to the board include those published or approved by the Defence and Civil Institute of Environmental Medicine (Canada) and the United States Navy.

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(1) Hyperbaric chambers shall conform to CSA Standard Z275.1-M1982, Hyperbaric Facilities and shall be on the dive site whenever

(a) dives exceed the no decompression limit, or

(b) the depth of 40 m (130 ft.) is exceeded.

(2) The diving supervisor shall identify the location of the nearest back-up hyperbaric facility suitable for the depth at which the diving operation is to be carried out and make arrangement for the emergency use of this facility.

(3) A hyperbaric chamber used in conjunction with a submersible compression chamber shall

(a) allow a person to transfer under pressure from the submersible compression chamber to the surface compression chamber and vice versa, and

(b) supply a breathing medium through a gas control panel that

i. clearly identifies the function of each valve and gauge, and

ii. is designed to prevent the accidental supply of an incorrect breathing medium.

(4) The hyperbaric chamber operator shall:

(a) operate the hyperbaric chambers in accordance with the requirements of C.S.A. Standard Z275.1-M1982, entitled "Hyperbaric Facilities",

(b) not control the chamber alone if he or she has been diving within the previous 4 hours, and

(c) ensure that effective means of communication are available between the dive site and a qualified medical practitioner knowledgeable in hyperbaric medicine.

(5) A diving operation exceeding the "no decompression limit" shall not be conducted unless a hyperbaric facility is available for the exclusive use of the divers engaged.

(6) When a diver shows any indication of pressure-related illness or requires therapeutic recompression, treatment shall be initiated and a qualified medical practitioner, knowledgeable in hyperbaric medicine, shall be alerted immediately.

(7) A diver who has suffered pressure-related illness shall not dive unless permitted by a qualified medical practitioner.

(8) The diving supervisor shall ensure that on completion of decompression, the diver remains under observation in the general area of the hyperbaric chamber for a period of time sufficient, in the opinion of the diving supervisor, to ensure the well being of the diver.

DIVING EQUIPMENT

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(1) All diving equipment and accessories necessary for the safe conduct of the diving operation shall

(a) be maintained to ensure its continuing operating integrity for the conditions, purposes, and depths for which it was designed,

(b) be examined, tested and repaired in accordance with the manufacturer's recommended procedures or as directed by the board; the employer shall keep a record of such maintenance, and

(c) not be used in a modified form unless the modification is specifically approved by an agency acceptable to the board.

(2) Gauges and metering equipment shall be checked every 6 months or whenever a discrepancy is indicated; any malfunctioning gauge or metering equipment shall be immediately removed from service and repaired without delay; if gauges and metering equipment are removed from service, such equipment shall be identified as having a malfunction.

(3) A compressor used to supply respirable air to a diver shall

(a) maintain a supply of respirable air at least double the volume of respirable air required at a pressure 25% greater than the maximum pressure requirement anticipated, and

(b) operate automatically without fluctuation of pressure in the air-tank or receiver.

(4) Compressors used to supply respirable air to divers shall

(a) discharge the compressed respirable air through filters into a suitable volume tank,

(b) have a non-return valve between the volume tank and the compressor,

(c) have a pressure gauge and drain cock, and

(d) have a separate connection and valve for each diver receiving respirable air from the volume tank.

(5) When respirable air is supplied by a compressor the supply intake shall be placed so that the breathing medium will not be contaminated by oil vapours, toxic, or noxious fumes or gases, or other objectionable impurities.

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(1) Systems supplying respirable oxygen shall

(a) use rigid piping systems whenever possible,

(b) not exceed a differential pressure of 700 kPa (102 p.s.i.) along any hose,

(c) not use quick-opening valves except for emergency shut-off at the point where the line enters the hyperbaric chamber, and

(d) use hoses and associated fittings constructed of materials that are compatible with oxygen at the operating volume and temperature.

(2) An area where oxygen is stored shall be

(a) adequately ventilated,

(b) properly identified with warning signs,

(c) equipped with a fire-suppression system, and

(d) kept clean.

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(1) A lifeline shall be

(a) secured at the surface to a safe point of anchorage,

(b) tended at all times by a diver's tender,

(c) secured in a manner that will prevent loss of contact with the diver, and

(d) of sufficient length and free of knots and splices.

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(1) The diving supervisor shall ensure that there is an effective two-way means of communication between the diver and the diver's tender or diving supervisor.

(2) Where voice communication is required, the communication system shall provide

(a) an effective reproduction adequate to enable the diver's voice to be clearly understood,

(b) a means of voice-unscrambling when mixed gas is used,

(c) a recording system for voice communication for depths exceeding 55 m (180 ft), and

(d) a separate emergency communication system between the diver and the diver's tender or diving supervisor.

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(1) The diver shall wear

(a) a sharp knife; and

(b) a diver indicator device such as a rescue beacon or strobe when SCUBA diving operations are to be carried on during the hours of darkness.

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(1) A surface diving base shall be equipped with the following:

(a) one complete spare set of underwater breathing apparatus with fully charged cylinders for emergency purposes, if SCUBA is being used,

(b) one shot line of 19 mm (3/4 inch) manila rope or equivalent marked at appropriate intervals, if the no decompression limit is to be exceeded,

(c) one complete set of decompression tables, and

(d) other equipment as may be specified by the board.

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(1) A hoisting device used to lower or raise the diver into or out of the water shall not be used for any other purpose until after the diver has been recovered; directions to the operator in charge of the hoisting device shall only be given by the diver, the diver’s tender, or the diving supervisor; the signal to stop may be given by anyone.

(2) A hoisting device used to raise or lower a stage or submersible compression chamber shall:

(a) be constructed so that the brake is automatically applied when the control is not held in the operating position, and

(b) not be fitted with a pawl-and- ratchet gear on which the pawl has to be disengaged before commencing raising or lowering operations.

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(1) A stage shall

(a) be large enough to carry at least 2 divers with their diving and associated equipment in uncramped conditions,

(b) be secure against tipping or spinning,

(c) not contain any equipment that might interfere with an occupant's foothold or handhold, and

(d) be constructed or equipped so that its occupants are secure against falling out of the stage.

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(1) An open bell shall

(a) be of sufficient size to accommodate all submerged divers,

(b) provide adequate emergency breathing medium for the safe decompression of divers in an emergency,

(c) be in contact with diving supervisor by a voice communication system, and

(d) contain equipment as may be specified by the board.

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(1) A submersible compression chamber shall conform to the requirements of CSA Standard Z275.1- M1982, entitled "Hyperbaric Facilities", and shall

(a) be of a design that permits divers to enter and exit without difficulty and provides seating for at least 2 dressed-in divers,

(b) contain adequate equipment, that is protected from inadvertent operation, for supplying the appropriate breathing medium to persons occupying or working from the chamber, and

(c) provide hoisting equipment capable of lifting an unconscious or injured diver into the chamber by a person located within.

(2) The diver's umbilical connected to the chamber shall be limited to 30 m (100 ft.) in length.

(3) Hoisting gear shall enable the submersible compression chamber to be lowered to the depth at which the diving operation is carried out without excessive lateral, vertical or rotational movement.

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(1) No diving operation shall be conducted from a lock-out submersible unless

(a) the submersible is negatively buoyant on the bottom or secured to the underwater work site,

(b) the diving supervisor is in the one atmosphere chamber during all external diving operations, and

(c) there is at least one other diver monitoring the diving operation from the lock-out submersible, dressed and ready to carry out emergency diving operations.

(2) The diver's umbilical connected to the locked out submersible shall be limited to 30 m (100 ft.) in length.

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(1) Where an atmospheric diving system is to be used, the diving supervisor shall locate the nearest back-up unit with capability of effecting a rescue and arrange for its emergency use.

(2) An atmospheric diving system shall have an onboard reserve life-support system which will sustain life for a period of time that would enable the back-up unit to reach the dive site and conduct the rescue.

SCUBA

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(1) Divers using SCUBA shall only use open circuit apparatus providing normal air by an automatic demand flow system.

(2) Recirculating apparatus shall be used only with the prior approval of the board.

(3) Each diver shall

(a) be in constant voice communication with the surface,

(b) be tended on a lifeline by a diver's tender,

(c) employ the buddy system whereby the divers shall remain at all times in constant visual or physical contact (where contact is lost both divers shall surface immediately), or

(d) employ other means of communication acceptable to the board.

(4) At least two divers and a diver's tender shall be present on each dive site when the diver will:

(a) not exceed 18.3 m (60 feet) in depth, and

(b) remain within the decompression limits, and

(c) be made under conditions in which the hazard of entrapment is known to be absent.

(5) On all other divers there shall be at least two operational divers, a dressed stand-by diver, and a diver's tender on the dive site.

(6) Subject to subsection (7) divers using SCUBA shall not dive to depths greater than 40 m (130 ft.).

(7) A diver using scuba may dive to depths greater than 40 m (130 ft.) for the purpose of saving life, but shall, where conditions permit,

(a) be secured by a life-line, and

(b) be tended by a qualified diver's tender.

(8) When divers are not tended on a lifeline a suitable boat, ready for immediate use, shall be available to recover the divers in the event of an emergency.

(9) Cylinders used to contain compressed respirable air shall be inspected, tested and stored in accordance with Canadian Standards Association Standard Z94.4-M1982 entitled "Selection, Care and Use of Respirators".

SURFACE-SUPPLY DIVING

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(1) The minimum diving crew on each diving site shall include

(a) for planned depths of less than 40 m (130 ft.)

i. diver

ii. stand-by diver

iii. diver’s tender

(b)for planned depths exceeding 40 m (130 ft.)

i. diver

ii. stand-by diver

iii. diving supervisor

iv. diver’s tender

(2) The diver's tender shall be a person acceptable to the diver and shall devote their whole time and attention to this work as a tender; except in an emergency, each diver in the water shall have a separate tender.

(3) The stand-by diver shall not dive except in an emergency.

(4) The stand-by diver shall not employ SCUBA whenever planned dives exceed 40 m (130 ft.); sufficient length of air-line to reach the submerged diver shall be provided for the stand-by diver.

(5) Stationary air-lines shall be protected against damage or interference and valves shall be

(a) fitted in each diver's air-line,

(b) readily accessible,

(c) guarded against interference, and

(d) clearly marked to identify the diver whose air supply it controls.

(6) All hoses, associated couplings and other fittings in use in any supply line shall be designed for their intended purpose; hoses shall be kink resistant and be capable of sustaining the required flow rates of the system used.

(7) The diver's supply hose shall be fitted with a pressure gauge downstream of the supply valve and installed in such a position that its dial figures are in clear view of the diver's tender.

(8) A diver who wears diving equipment that does not have a residual volume of breathing medium which would permit the diver to reach an emergency breathing supply shall wear a bailing out system, with appropriate breathing medium.

(9) Non-return valves shall be fitted to diving helmets and surface-supplied masks. They shall be checked daily and before the commencement of diving operations in a manner recommended by the manufacturer.

(10) The umbilical shall incorporate the lifeline in such a manner to prevent stress on the diver's supply hose and fittings.

(11) Each surface-supplied diver shall have effective two-way communication with the surface.

(12) Liveboating shall only be conducted

(a) in times of good visibility and calm water,

(b) from vessels with sufficient manoeuvrability to conduct the operation,

(c) with an effective method to prevent the diver's umbilical from becoming entangled in the propellers,

(d) where the diver wears a bail -out system, and

(e) where the vessel captain is competent to perform liveboating operations and is acceptable to the diving supervisor.

DEEP DIVING

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(1) In deep diving the diver shall

(a) be tethered to the work base by an umbilical, and

(b) be provided with effective two-way voice communication in accordance with section 26.

(2) Mixed gas shall be used as the breathing medium for depths exceeding 55 m (180 ft).

(3) Open bells, submersible compression chambers, or lock-out submersibles shall be provided and used to transport the diver to the underwater work site whenever a dive exceeds the following depth and bottom time limits:

DEPTH AND BOTTOM TIME LIMITS
Bottom Time Minutes Depth
m ft
60 55 - 68 180 - 224
40 68 - 75 225 - 249
30 75 - 90 250 - 300

(4) A stage, open bell, submersible compression chamber or lock-out submersible shall be provided to transport the divers to the underwater work site where the depth and bottom time of the dive do not exceed the depth and bottom time limits in paragraph (6)(a).

(5) A submersible compression chamber or lock-out submersible shall be used where the depth and bottom time exceed the limits given in subsection (3) or to all depths in excess of 90 m (300 ft.).

(6) Diving activities shall not be carried out at water depths greater than 55 m (180 ft.) unless:

(a) the divers are transported through the air-water interface by a suitable submersible compression chamber, open bell, or stage,

(b) the stand-by diver is located at the surface or in the stage,

(c) all divers, stand-by divers, and diver's tender are in voice communication with each other, and

(d) the diver's tender has a means of monitoring the depth and the breathing medium pressures of the diver and stand-by diver.

(7) Where bounce (non-saturation) diving techniques are used, the diving supervisor shall ensure that no diver remains submerged more than 3 hours in a 24-hour period and that there is a rest period of at least 12 continuous hours after this limit has been reached before the next dive.

(8) Where saturation diving techniques are used, the diving supervisor shall ensure that

(a) where the dive is to a depth of 150 m (492 ft.) or less, no diver exceeds 4 hours in the water and 4 hours as a diver's tender in the submersible compression chamber,

(b) where the dive is deeper than 150 m (492 ft.), no diver exceeds 3 hours in the water and 3 hours as diver's tender in the submersible compression chamber, and

(c) in any 24-hour period, there is a rest period of at least 12 continuous hours after the time limits specified in paragraphs 2(a) and (b) have been reached.

(9) No diver shall commence another dive within 7 days of completion of decompression following a saturation dive.

(10) Each diver shall be tended by

(a) a diver's tender on the surface,

(b) a diver's tender in a submersible compression chamber or stage, or

(c) another diver in the water who is also tended by a diver's tender.

(11) Where a submersible compression chamber is used, at least one diver shall remain in the chamber to tend the diver who has left the chamber.

(12) A minimum diving crew of 5 shall be present at each deep diving operation including

(a) 1 diving supervisor,

(b) 2 divers, and

(c) 2 diver's tenders.

(13) The diving supervisor shall ensure that there is a secondary source of power which shall be capable of

(a) being rapidly brought on line,

(b) operating the handling system for the submersible compression chamber,

(c) heating the diving plant and equipment, including heating for any diver in the water,

(d) sustaining life-support systems for compression chambers and any diver in the water,

(e) illuminating the work site of divers and the interior of compression chambers, dive station, and

(f) operating communication and monitoring systems.