(SSMT Ordinance No. 24, September 14, 1983)
This Annex addresses work under compressed air and submerged work.
1. WORK UNDER COMPRESSED AIR
(Amended by SSMT Ordinance No. 05, February 9, 1983)
1.1 Work under compressed air refers to tasks performed in environments where workers are subjected to pressures higher than atmospheric pressure and where careful decompression is required, according to the attached tables.
1.2 For the purposes of this item, the following definitions apply:
a) Working Chamber – The space or compartment under compressed air where the work is being carried out.
b) Recompression Chamber – A chamber, separate from the working chamber, used for treating individuals with decompression sickness or embolism, directly supervised by a qualified doctor.
c) Bell – A chamber through which the worker passes from open air to the working chamber of the caisson and vice versa.
d) Personnel Lock – A chamber through which the worker passes from open air to the working chamber of the tunnel and vice versa.
e) Compressed Air Supervisor – A trained professional knowledgeable in various techniques used in work under compressed air, designated by the employer as the immediate supervisor of the workers.
f) Qualified Doctor – An occupational physician with proven knowledge in Hyperbaric Medicine, responsible for supervision and the medical program.
g) Lock or Bell Operator – An individual trained in the compression and decompression operations of locks or bells, responsible for controlling the pressure inside.
h) Working Period – The time during which the worker is subjected to pressure higher than atmospheric pressure, excluding the decompression period.
i) Working Pressure – The highest air pressure to which the worker is subjected in the caisson or tunnel during the working period.
j) Pressurized Tunnel – An excavation below the ground surface with its major axis at an angle not exceeding 45 degrees to the horizontal, sealed at both ends, with internal pressure above atmospheric pressure.
l) Compressed Air Caisson – A vertical structure extending below the water or soil surface, through which workers descend via the bell to a pressure higher than atmospheric. The pressurized atmosphere counteracts the water pressure, allowing work inside.
1.3 The provisions of this item apply to work under compressed air in pneumatic caissons and pressurized tunnels.
1.3.1 All work under compressed air must be carried out in accordance with the following prescriptions, and any modifications must be previously approved by the national competent authority in occupational safety and health.
1.3.2 A worker must not undergo more than one compression within a 24-hour period.
1.3.3 During work under compressed air, no person shall be exposed to pressure above 3.4 kgf/cm², except in emergencies or during treatment in a recompression chamber under the direct supervision of the responsible physician.
1.3.4 The duration of the work period under compressed air shall not exceed 8 hours at working pressures of 0 to 1.0 kgf/cm², 6 hours at working pressures of 1.1 to 2.5 kgf/cm², and 4 hours at working pressures of 2.6 to 3.4 kgf/cm².
1.3.5 After decompression, workers are required to remain at the worksite for at least 2 hours for medical observation.
1.3.5.1 The appropriate location for the observation period must be designated by the responsible physician.
1.3.6 For work under compressed air, employees must meet the following requirements:
a) Be over 18 and under 45 years of age;
b) Undergo mandatory pre-employment and periodic medical examinations as required by the specific characteristics and peculiarities of the work;
c) Carry an identification plate, according to the attached model (Table I), issued at the time of hiring after the medical examination.
1.3.7 Before starting the work shift, workers must be inspected by the physician. Those showing signs of respiratory infections or other illnesses shall not be allowed to work.
1.3.7.1 It is prohibited to work if the individual appears intoxicated or shows signs of alcohol consumption.
1.3.8 The consumption of carbonated beverages and smoking inside caissons and tunnels is prohibited.
1.3.9 Appropriate facilities for medical assistance, recovery, food, and personal hygiene for workers under compressed air must be available near the worksite.
1.3.10 All employees assigned to work under compressed air must be educated about the risks and precautions through audiovisual training.
1.3.11 Any employee without prior experience in work under compressed air must be supervised by a competent person and must be accompanied by a skilled person in the bell during compression to instruct them on proper behavior during compression.
1.3.12 Work crews must be supervised and directed by a compressed air supervisor.
1.3.13 For remuneration purposes, the work period includes the working period, compression time, decompression time, and the medical observation period.
1.3.14 Medical supervision for work under compressed air must comply with the following conditions:
a) Medical assistance by a qualified doctor must be provided whenever there is work under compressed air, along with an appropriate medical facility;
b) Each worker under compressed air must have a medical record where all examination data is recorded;
c) No employee may work under compressed air without being examined by a qualified doctor, who will certify in the individual record that the person is fit for the work;
d) A candidate deemed unfit may not perform the job until the unfitness condition is resolved;
e) The fitness certificate is valid for 6 months;
f) In case of absence from work for more than 10 days or sick leave, the employee must undergo a new medical examination upon return.
1.3.15 Requirements for Operations in Bells or Locks.
1.3.15.1 At least one person trained in this type of work with the authority to enforce compliance with all safety measures must be present at the site.
1.3.15.2 Compression and decompression operations must be conducted using external devices operated by the lock or bell operator. Internal controls must also be available but used only in emergencies. Control devices must be calibrated at the start of each work shift.
1.3.15.3 The lock or bell operator must record the following for each person in an appropriate log (Table II):
a) Exact time of entry and exit from the bell or lock;
b) Working pressure;
c) Exact time of the start and end of decompression.
1.3.15.4 If external controls cannot be used, internal pressure controls must be arranged so that a person inside the bell, preferably the foreman, operates them under the supervision of the lock or bell operator.
1.3.15.5 Ventilation and temperature conditions must comply with the following:
a) Continuous ventilation must be provided at a minimum rate of 30 cubic feet/minute per person during the workers’ stay in the working chamber, bell, or lock;
b) The temperature inside the bell, lock, or working chamber must not exceed 27°C (wet-bulb temperature), achievable by cooling the air with appropriate devices (coolers) before entry or through other control measures;
c) Air quality must meet the purity standards specified in subitem 1.3.15.6, using appropriate filters placed between the air source and the working chamber, bell, or lock.
1.3.15.6 Tolerance Limits for Contaminants:
- Oxygen: More than 20%
- Carbon monoxide: 20 ppm
- Carbon dioxide: 2,500 ppm
- Oil or particulate matter: 5 mg/m³ (PT>2 kgf/cm²), 3 mg/m³ (PT<2 kgf/cm²)
- Methane: 10% of the lower explosive limit
1.3.15.7 Communication between the interior of the compressed air environments and the exterior must be maintained through a telephone system or similar.
1.3.16 Worker compression must follow these rules:
a) In the first minute after compression begins, the pressure increase must not exceed 0.3 kgf/cm²;
b) After reaching 0.3 kgf/cm², the pressure may only be increased after an interval allowing the supervisor to observe if all individuals in the bell are in good condition;
c) After the observation period, the pressure increase must not exceed 0.7 kgf/cm² per minute to prevent discomfort;
d) If any worker experiences discomfort, earache, or headache, compression must be immediately stopped, and the supervisor will gradually reduce the bell’s pressure until recovery occurs. If recovery does not occur, decompression will continue to atmospheric pressure, and the individual will be removed for medical attention.
1.3.17 Decompression of workers exposed to pressures from 0.0 to 3.4 kgf/cm² will follow the attached tables (Table III) according to these rules:
a) If two or more people are being decompressed in the same bell or lock and their work periods or pressures differ, decompression will proceed based on the longest work period or highest pressure experienced by the workers;
b) The pressure will be reduced at a rate not exceeding 0.4 kgf/cm² per minute until the first decompression stage per the attached tables. The bell or lock must be held at that pressure for the indicated time in minutes, then reduced at the same previous rate to the next stage, and so on. For every 5 minutes of stop, the bell must be ventilated for 1 minute.
1.3.18 Treatment of decompression sickness or air embolism will follow the treatment tables of VAN DER AUER and WORKMAN and GOODMAN.
1.3.19 Activities or operations under compressed air are considered of the highest degree of unhealthiness.
1.3.20 Non-compliance with this item constitutes a serious and imminent risk for the purposes and effects of NR-3.
TABLE I
MODEL OF IDENTIFICATION PLATE FOR WORK IN COMPRESSED AIR ENVIRONMENT
| IN CASE OF UNCONSCIOUSNESS OR ILLNESS OF UNDETERMINED CAUSE CALL NO. _____ AND REFER THE PERSON TO ____ |
| COMPANY NAME NAME OF WORKER ATTENTION: WORKS WITH COMPRESSED AIR |
The plate should be a rectangle measuring 4 cm in height and 6 cm in width. The material should be aluminum with a thickness of 2 mm.
TABLE II
WORK RECORD SHEET FOR COMPRESSED AIR WORK
| COMPANY | DATE | |||||||
| PROJECT | NAME OF SUPERVISOR | |||||||
| NAME | POSITION | COMPRESSION | DECOMPRESSION | |||||
| WORKING PRESSURE | ENTRY TIME | WORK PERIOD | START | END | DURATION | NOTES | ||
TABLE III
DECOMPRESSION TABLE
Working Pressure from 0 to 0.900 kgf/cm²
| WORK PERIOD (HOURS) | DECOMPRESSION STAGE 0.3 kgf/cm² | TOTAL DECOMPRESSION TIME |
|---|---|---|
| 0 to 6:00 | 4 min. | 7 min. |
| 6 to 8:00 | 14 min. | 17 min. |
| + than 8:00** | 30 min. | 33 min. |
NOTES: The decompression rate between stages should not exceed 0.3 kgf/cm² per minute.
* Included decompression time between stages.
** Only in exceptional cases, not exceeding 12 hours.
DECOMPRESSION TABLE
Work period from ½ to 1 hour.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 1 hour to 1 ½ hour.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 1 hour 30 minutes to 2 hours.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 2 hours to 2 hours 30 minutes.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 2 hours 30 minutes to 3 hours.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 3 hours to 4 hours.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 4 hours to 6 hours.****
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
**** Up to 8 (eight) hours for a working pressure of 1.0 kg/cm² and up to 6 (six) hours for the other pressures.
DECOMPRESSION TABLE
Work period from 0 to 30 minutes.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 30 minutes to 1 hour.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 1 hour to 1 hour 30 minutes.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 1 hour 30 minutes to 2 hours.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 2 hours to 2 hours 30 minutes.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 2 hours 30 minutes to 3 hours.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 3 hours to 4 hours.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
DECOMPRESSION TABLE
Work period from 4 hours to 6 hours.
NOTES:
(*) Decompression for both the 1st stage and subsequent stages should be done at a rate not exceeding 0.4 kgf/cm² per minute.
(**) Time between stages is not included.
(***) For the working pressure limit values, use the highest decompression.
(****) The work period plus the decompression time (including the time between stages) must not exceed 12 hours.
2. SUBMERGED WORK
(Amended by SSMT Ordinance No. 24, September 14, 1983)
2.1 For the purposes of this item, the following definitions apply:
I – Sheltered Waters: any body of water that, due to natural or artificial protection, is not subject to wave impact or currents exceeding 1 knot.
II – Hyperbaric Chamber: a pressure vessel specially designed for human occupancy, in which occupants can be subjected to hyperbaric conditions.
III – Surface Chamber: a hyperbaric chamber specially designed for decompression of divers, required by the operation or for hyperbaric treatment.
IV – Atmospheric Pressure Submersible Chamber: a chamber resistant to external pressure, specially designed for underwater use, in which occupants remain under atmospheric pressure.
V – Therapeutic Chamber: a surface chamber intended exclusively for hyperbaric treatment.
VI – Vessel Commander: the person responsible for the vessel that supports submerged work.
VII – Hyperbaric Condition: any condition in which the ambient pressure is greater than atmospheric pressure.
VIII – Hazardous Conditions: situations in which a diving operation involves additional risks or adverse conditions, such as:
a) use and handling of explosives;
b) underwater cutting and welding work;
c) open sea work;
d) currents exceeding 2 knots;
e) sea state above “slight sea” (maximum wave height of 2 meters);
f) weight maneuvers or work with tools that prevent the diver from controlling buoyancy;
g) night work;
h) work in confined environments.
IX – Contractor: a natural or legal person who contracts diving services or for whom these services are performed.
X – Decompression: the set of procedures through which a diver eliminates excess inert gases absorbed during certain hyperbaric conditions, necessary for the preservation of physical integrity when returning to atmospheric pressure.
XI – Emergency: any abnormal condition capable of affecting the diver’s health or the safety of the diving operation.
XII – Employer: a natural or legal person responsible for providing services, employing divers.
XIII – Self-Contained Diving Equipment: equipment in which the supply of the breathing mixture is carried by the diver and used as the sole source.
XIV – Lifeline: a cable, handled from the location of the dive, that connects to the diver, allowing for recovery and hoisting from the water with their equipment.
XV – Open Sea: any area under the direct influence of the high sea.
XVI – Hyperbaric Doctor: a doctor with a hyperbaric medicine course approved by SSMT/MTb, responsible for conducting admission, periodic, and termination physical exams in accordance with Annexes A and B and NR 7.
XVII – Diver: a qualified and legally certified professional for the use of diving equipment underwater.
XVIII – Intervention Dive: a dive characterized by the following conditions:
a) use of artificial breathing mixtures;
b) work time at depth limited to values not requiring saturation techniques.
XIX – Artificial Breathing Mixtures: mixtures of oxygen, helium, or other gases suitable for breathing during underwater work when natural air is not recommended.
XX – Diving Operation: any operation involving underwater work from initial preparation procedures to the end of the observation period.
XXI – Observation Period: the period beginning when the diver is no longer under hyperbaric conditions and extending:
a) up to 12 hours for air dives;
b) up to 24 hours for dives with artificial breathing mixtures.
XXII – Diving Platform: a ship, vessel, barge, fixed or floating structure, construction site, shipyard, dock, or location from which the dive is conducted.
XXIII – Ambient Pressure: the pressure of the environment surrounding the diver.
XXIV – Medical Program: the set of activities developed by the employer in the medical area necessary to maintain the health and physical integrity of the diver.
XXV – Safety Rules: the basic procedures that must be observed in diving operations to ensure their safe execution and the physical integrity of divers.
XXVI – Open Bell: a bell with an open bottom and a platform that shelters and allows the transport of at least 2 divers from the surface to the work site, with a communication system, emergency gas supply, and viewports for external observation.
XXVII – Diving Bell: a hyperbaric chamber specially designed for underwater work.
XXVIII – Diving System: the set of equipment necessary for the safe execution of diving operations.
XXIX – Diving Supervisor: a qualified and legally certified diver designated by the employer to supervise the diving operation.
XXX – Saturation Techniques: procedures by which a diver avoids repeated decompressions to atmospheric pressure, remaining under ambient pressure greater than that, so that their body remains saturated with inert gases from the breathing mixtures.
XXXI – Saturation Technician: a properly qualified professional for applying appropriate techniques to saturation operations.
XXXII – Submerged Work: any work performed or conducted by a diver in a liquid environment.
XXXIII – Umbilical: the set of lifeline, breathing supply hose, and other components necessary for the safe execution of the dive, according to its complexity.
2.1.1 The course referred to in item XVI of subitem 2.1 can be offered by institutions recognized and authorized by the MEC and accredited by FUNDACENTRO to offer the said course.
2.1.2 Accreditation with FUNDACENTRO referred to in subitem 2.1.1 and the registration of the hyperbaric doctor with SSMT/MTb will be done according to the norms for accreditation and registration in the field of occupational safety and medicine.
2.2 Obligations of the Contractor
2.2.1 The contractor is responsible for:
a) requiring the employer, through the contractual instrument, to ensure that services are developed in accordance with the provisions of this item;
b) requiring the employer to present a Registration Certificate issued by the Directorate of Ports and Coasts (DPC);
c) providing all means within their reach for emergency assistance when requested by the diving supervisor.
2.3 Obligations of the Employer
2.3.1 The employer is responsible for:
a) ensuring that all diving operations comply with this item;
b) keeping complete operation manuals, appropriate equipment, and decompression tables available for diving teams at work sites;
c) specifying in writing the team members and their functions;
d) immediately reporting accidents or risk situations occurring during the diving operation to the Maritime Labor Office of the region, through a detailed report;
e) ensuring that divers’ medical certificates are up to date;
f) ensuring health inspections are conducted according to the provisions of subitem 2.9 and providing adequate conditions for conducting occupational medical exams;
g) ensuring the application of the medical program to their divers and ensuring efficient communications and means for rapid transportation of a qualified doctor to the operation site in case of an accident;
h) providing the diving team with provisions, work clothes, and equipment, including personal protective equipment necessary for safely conducting planned operations;
i) ensuring that equipment is in perfect working condition and that warranty certificates are valid;
j) providing means to ensure compliance with normal and emergency procedures necessary for the safety of the diving operation and the physical integrity of those involved;
l) immediately providing competent authorities with all information regarding operations, diving equipment, and personnel involved when requested;
m) stamping and signing the divers’ logbooks related to the diving operations they participated in;
n) keeping Records of Diving Operations and other necessary records for at least 5 years from the date of their occurrence;
o) providing the teams with adequate accommodation, food, and transportation conditions.
2.4 Obligations of the Vessel Commander or Diving Platform Manager
2.4.1 The vessel commander or diving platform manager is responsible for:
a) not allowing any activity that may pose a danger to divers supported by the vessel, consulting the diving supervisor about activities that may affect the safety of the operation before dives begin;
b) making available to the supervisor, when requested, during diving operations and in emergencies, all equipment, space, or facilities necessary to ensure the physical integrity of the divers;
c) ensuring that no maneuver is performed and no machine or equipment operates if it poses a danger to divers in operation;
d) providing the diving supervisor with weather forecasts for the operation area before the start of the operation and at convenient intervals during the operation;
e) warning nearby vessels of the diving operation using appropriate and efficient signaling and buoying methods.
2.5 Obligations of the Diving Supervisor
2.5.1 The diving supervisor is responsible for:
a) assuming direct control of the operation for which they were designated;
b) only allowing the diving operation to be conducted as prescribed in this item;
c) signing the logbook of each diver participating in the operation;
d) not diving during the diving operation while acting as a supervisor;
e) only allowing legally qualified and fit individuals to participate in the operation;
f) deciding with other supervisors, when two or more are designated for an operation, the periods of responsibility for each;
g) maintaining and preserving the records specified in subitem 2.12;
h) establishing with the vessel commander or diving platform manager the measures necessary for the smooth and safe conduct of the diving operation before it begins;
i) requesting the presence of a qualified doctor at the diving operation site when specialized medical treatment is needed;
j) not allowing the diving operation to proceed if adequate normal and emergency equipment is not available in sufficient quantity for safe conduct;
l) promptly informing the employer of all accidents or risk situations occurring during the operation, including individual reports submitted by divers.
2.6 Duties of Divers
2.6.1 Divers are responsible for:
a) always carrying their Diver’s Logbook (LRM);
b) presenting the LRM whenever requested by the competent authority, employer, contractor, or supervisor;
c) ensuring records are made for all diving operations they participated in as soon as possible, being legally responsible for the entries;
d) informing the diving supervisor if they are physically unfit or if there is any other reason preventing them from being subjected to hyperbaric conditions;
e) keeping their LRM for at least 5 years from the date of the last entry;
f) complying with safety rules and other provisions of this item;
g) reporting irregularities observed during the diving operation to the supervisor;
h) presenting themselves for a medical examination when required by the employer;
i) ensuring, before the operation begins, that the individual equipment provided by the employer is in perfect working condition.
2.7 Classification of Divers
2.7.1 Divers are classified into two categories:
a) MR – divers qualified only for diving operations using compressed air;
b) MP – divers duly qualified for diving operations requiring the use of artificial breathing mixtures.
2.8 Diving Teams
2.8.1 The basic team for diving with “compressed air” to a depth of 50 meters and in the absence of hazardous conditions defined in item VIII of subitem 2.1 shall consist of the following, provided that only water decompression is planned:
a) 1 supervisor;
b) 1 diver to perform the work;
c) 1 standby diver ready to intervene in an emergency;
d) 1 surface assistant.
2.8.1.1 In sheltered waters, under the conditions described in subitem 2.8.1, considering the nature of the work and provided the depth does not exceed 12 meters, the basic team may be reduced by one surface assistant.
2.8.2 When decompression in a surface chamber is planned for dives under the conditions stipulated in subitem 2.8.1, the basic team shall include one additional diver to act as a chamber operator.
2.8.3 In the presence of any hazardous conditions enumerated in item VIII of subitem 2.1, the teams described in subitems 2.8.1 and 2.8.2 shall include one additional diver, making a total of 5 and 6 men, respectively.
2.8.4 In any diving operation where the planned work requires the simultaneous deployment of two or more divers in the water, there must be at least one standby diver for every two submerged divers.
2.8.5 In operations beyond 50 meters, or when using self-contained equipment, at least two submerged divers must always be employed, so that one can assist the other if necessary.
2.8.6 In intervention dives using Artificial Breathing Mixtures, the diving teams shall consist of the following:
a) up to a depth of 120 meters:
- 1 supervisor
- 2 divers
- 1 diver responsible for bell operation
- 1 auxiliary diver
- 1 standby diver to respond to possible emergencies b) from 120 meters to 130 meters:
- all the elements above plus 1 diver responsible for operating the hyperbaric chamber.
2.8.7 In operations using saturation techniques, there shall be at least 2 supervisors and 2 saturation technicians.
2.9 Medical Examinations
2.9.1 It is mandatory to conduct medical examinations within the standards established in this subitem for professional diving activities.
2.9.2 Medical examinations are divided into two categories:
a) pre-admission examination for selecting candidates for diving activities;
b) periodic examination for monitoring personnel in diving activities.
2.9.3 Medical examinations are only valid and authorize the diver for activity if performed by a qualified doctor.
2.9.4 The qualified doctor is also responsible for conducting pressure and oxygen tolerance tests.
2.9.5 Examinations shall be conducted according to the psychophysical standards established in Annexes A and B.
2.9.6 The doctor will conclude the reports in one of the following ways:
a) fit for diving (physical and mental integrity);
b) temporarily unfit for diving (temporary pathology);
c) permanently unfit for diving (permanent and/or progressive pathology).
2.9.7 Medical examinations of divers shall be conducted under the following conditions:
a) upon admission;
b) every 6 months for all personnel actively engaged in diving activities;
c) immediately after an accident occurring during diving activities or a serious illness;
d) after the end of temporary incapacity;
e) in special situations, at the diver’s request or the employer’s request.
2.9.7.1 The medical examinations referred to in the previous subitem are only valid when conducted within the national territory.
2.9.8 The complementary examinations provided in Annexes A and B are valid for 12 months, and the qualified doctor may request any examination deemed necessary at any time.
2.10 Safety Rules for Diving
2.10.1 Verbal communications are mandatory in all diving operations conducted under hazardous conditions, and in dives with Artificial Breathing Mixtures (MRA), instruments capable of correcting sound distortions caused by gases in voice transmission must be included.
2.10.2 In dives deeper than 50 meters using a diving bell or atmospheric pressure submersible chamber, a wireless intercom allowing verbal communications must be available for emergencies.
2.10.3 All diving operations must use appropriate buoying and signaling according to the international code of signals and other measures deemed necessary for safety.
2.10.4 Surface-supplied diving techniques shall always be used, except in special cases where safety conditions indicate that self-contained diving techniques are more appropriate, supported by a small boat.
2.10.5 Umbilicals or lifelines must always be attached to suitable harnesses that can support the diver’s weight and equipment.
2.10.6 Entry and exit of divers into the liquid environment must always be facilitated using baskets, water-level decks, or rigid ladders.
2.10.7 Dives requiring decompression should only be planned for situations where a surface chamber, as specified in subitem 2.11.20 and ready to operate, can be reached within 1 hour using available transportation at the site.
2.10.7.1 If the depth exceeds 40 meters or decompression time exceeds 20 minutes, a surface chamber conforming to subitem 2.11.20 must be present at the dive site.
2.10.8 Whenever it is necessary to pressurize or decompress a diver, a second person must accompany them inside the chamber.
2.10.9 The use of single-compartment chambers is only permitted in emergencies for transporting an injured person to a facility with a double-compartment chamber.
2.10.10 In diving operations where a surface chamber is required, the second dive can only begin after the observation period of the previous dive ends unless a second chamber and sufficient personnel to operate it are available.
2.10.11 During the observation period, surface chambers must be unoccupied and ready for use to meet possible recompression needs.
2.10.11.1 During the observation period, the supervisor and other necessary team members for conducting recompression must remain at the site.
2.10.12 During the observation period, divers are not permitted to:
a) perform another dive, except using appropriate tables for successive dives;
b) fly above 600 meters;
c) engage in excessive physical exertion;
d) leave the chamber location if the dive involved using artificial breathing mixtures.
2.10.13 In diving operations specified in this subitem, the following must be observed:
a) Dive with self-contained compressed air equipment: maximum depth equal to 40 meters;
b) Dive with surface-supplied compressed air equipment: maximum depth equal to 50 meters;
c) Dive without open bell support: maximum depth equal to 50 meters;
d) Intervention dive with artificial breathing mixture (MRA) supported by an open bell: maximum depth equal to 90 meters;
e) Intervention dive with artificial breathing mixture (MRA) supported by a diving bell: maximum depth equal to 130 meters.
2.10.13.1 Depths from 120 to 130 meters can only be reached using saturation techniques.
2.10.13.2 Diving operations at depths exceeding 130 meters can only be performed using saturation techniques.
2.10.13.3 At depths exceeding 90 meters, any diving operation must use a diving bell with a surface chamber equipped with all necessary accessories and equipment, limiting the depth to the maximum working pressure of that chamber.
2.10.13.4 The maximum daily submerged time for dives using compressed air must not exceed 4 hours, and the following limits must also be observed:
a) Self-contained equipment: bottom time must stay within no-decompression limits defined in the attached tables;
b) Surface-supplied equipment: bottom time must be less than the limits defined in the exceptional diving tables in the attachment.
2.10.13.5 Using artificial breathing mixture (MRA) in intervention dives with an open bell, the diver’s water immersion time must not exceed 160 minutes.
2.10.13.6 Using artificial breathing mixture (MRA) in intervention dives with a diving bell, the bottom time must not exceed:
a) 90 minutes for dives up to 90 meters;
b) 60 minutes for dives between 90 to 120 meters;
c) 30 minutes for dives between 120 to 130 meters.
2.10.13.7 Using saturation techniques, the maximum submerged period for each diver, including time inside the bell, must not exceed 8 hours in each 24-hour period.
2.10.13.8 Using saturation techniques, the maximum time under pressure will be 28 days, and the minimum interval between two saturations will be equal to the saturation time, not less than 14 days. The total time under saturation in 12 consecutive months must not exceed 120 days.
2.10.14 At depths exceeding 150 meters, the artificial breathing mixture (MRA) must be adequately heated for the diver’s supply.
2.10.15 Diving from non-anchored vessels is only permitted if the diving supervisor deems this procedure safe and appropriate measures are taken to protect the diver against propulsion systems, water flow, and obstacles.
2.10.15.1 These dives are only permitted during daylight unless conducted from a dynamically positioned vessel approved by the Directorate of Ports and Coasts (DPC) for this type of operation.
2.10.16 Any electrical equipment used underwater must have safety devices preventing high voltages or currents that may endanger the diver in case of malfunction.
2.10.17 The diving supervisor must not keep any diver submerged or under hyperbaric conditions against their will, except when necessary to complete decompression or for hyperbaric treatment.
2.10.17.1 A diver refusing to start a dive or remain under hyperbaric conditions without justifiable reasons may face sanctions according to relevant legislation.
2.10.18 Any diving operation must be interrupted or canceled by the diving supervisor if safety conditions do not permit its execution or continuation.
2.10.19 The distance traveled by the diver between the diving bell and the actual work site may only exceed 33 meters in special situations, meeting the following requirements:
a) there is no other alternative for conducting the diving operation without exceeding this distance. In this case, the Contractor is responsible for determining the use of the umbilical to cover the distance exceeding 33 meters, after consulting the diving supervisor and the commander or responsible person for the diving platform;
b) the diving operation is conducted during daylight;
c) the route between the diving bell and the actual submerged work site is inspected by an underwater TV camera;
d) a guide cable is extended between the diving bell and the work site by a remote-controlled vehicle or the first diver;
e) the distance traveled by the diver does not exceed 60 meters;
f) emergency cylinders are used to ensure the diver’s return to the bell, based on a respiratory consumption rate of 60 liters per minute at the considered depth, with a 3-minute autonomy;
g) a system with at least two alternatives for gas supply, heating, and communications is used;
h) a neutrally buoyant umbilical is used.
2.10.19.1 If visibility conditions do not allow complete observation of the diver’s route by a fixed TV camera, a camera installed on a remotely operated vehicle must be used.
2.10.19.2 Divers using umbilicals for distances exceeding 33 meters must receive prior rescue and return training to the bell in an emergency, duly recorded in the Diver’s Logbook.
2.10.20 No diving operation can be conducted without a system and equipment review within 12 hours before the dive.
2.10.21 All members of the diving teams, especially supervisors, must take the necessary precautions related to the safety of operations concerning planning, preparation, execution, and emergency procedures, as detailed below:
I – Regarding Planning:
a) meteorological conditions;
b) sea conditions;
c) vessel movements;
d) underwater hazards, including drains, suction pumps, or locations where the hydrostatic pressure difference may create a danger for divers;
e) depth and type of operation to be performed;
f) equipment adequacy;
g) personnel availability and qualification;
h) exposure to atmospheric pressure drops caused by air transport after the dive;
i) simultaneous diving operations.
II – Regarding Preparation:
a) obtaining information from responsible parties about any activities in the area that may interfere with the operation and affect its safety;
b) selecting equipment and breathing mixtures;
c) checking systems and equipment;
d) assigning tasks among team members;
e) ensuring divers are qualified for the work;
f) signaling procedures;
g) precautions against potential hazards at the work site.
III – Regarding Execution:
a) responsibility of all involved personnel;
b) correct use of individual equipment;
c) appropriate supply and composition of breathing mixtures;
d) locations from which the operation can be conducted;
e) operations related to submersible compression chambers;
f) identification and characteristics of work sites;
g) use of tools and other equipment by divers;
h) depth and work time limits;
i) descent, ascent, and rescue of the submersible compression chamber and divers;
j) decompression tables, including treatment and correction tables;
l) control of initial condition changes;
m) observation period;
n) maintenance of dive records.
IV – Regarding Emergency Procedures:
a) signaling;
b) assistance in water and on the surface;
c) availability of surface or therapeutic chambers;
d) first aid;
e) specialized medical assistance;
f) communication and transport for emergency services and equipment;
g) possible need for evacuation of work sites;
h) various supplies to address emergencies.
2.11 Diving Equipment
2.11.1 Systems and equipment must be installed in suitable locations to ensure the safety of operations.
2.11.2 Diving equipment used in operations must have an approval certificate issued or homologated by the Directorate of Ports and Coasts (DPC).
2.11.3 Pressure vessels must display in indelible and visible characters:
a) maximum working and safety limits;
b) name of the approving entity;
c) validity period of the certificate;
d) date of the last rupture test.
2.11.4 The certificate referred to in subitem 2.11.2 is invalid if:
a) any alteration or repair is made to the system or equipment, altering its original characteristics;
b) the periods established in the table below for leak tests and rupture tests are exceeded.
| Equipment | Leak Tests | Rupture Tests |
| Hyperbaric Chambers | 2 years | 5 years |
| Non-submersible Gas Reservoirs | 5 years | 5 years |
| Submersible Gas Reservoirs | 2 years | 5 years |
| Equipment with working pressure > 500 mbar | 2 years | 2 years |
2.11.5 The rupture test pressure for equipment must be equal to 1.5 times the maximum working pressure for which it was designed.
2.11.6 Preferably, hydrostatic tests will be used; however, if not possible, pneumatic tests can be conducted with sufficient safety precautions for personnel in case of structural failure.
2.11.7 Systems and equipment must include a means of supplying divers with an adequate breathing mixture (including a reserve supply for emergencies or therapeutic recompression) in volume, temperature, and pressure capable of supporting vigorous and prolonged physical effort during the operation.
2.11.8 All equipment operating with recycled breathing mixtures must be certified by a recognized entity approved by the Directorate of Ports and Coasts (DPC) for its capacity to provide breathing mixtures in the required standards and quantity.
2.11.9 All breathing mixture compressors, especially air compressors, must be installed to avoid the risk of aspirating gases from their engine discharge or environments where contamination is possible (engine rooms, holds, etc.).
2.11.10 All gas reservoirs must have safety devices operating at the maximum working pressure.
2.11.11 Gases or breathing mixtures supplied in reservoirs for diving operations can only be used if accompanied by the following specifications:
a) percentage of constituent elements;
b) purity grade;
c) type of analysis performed;
d) name and signature of the person responsible for the analysis.
2.11.12 Artificial Breathing Mixtures must be analyzed at the operation site for oxygen percentages and clearly marked on the reservoirs with the name and composition of the contents.
2.11.13 The diving team must always be able to analyze the Artificial Breathing Mixtures used at the operation site for:
a) oxygen percentage;
b) carbon dioxide percentage;
c) carbon monoxide percentage.
2.11.14 A diving operation can only be conducted if a quantity of gases is available on-site, at least three times the amount needed to pressurize the hyperbaric chambers at the maximum working depth during a normal operation.
2.11.14.1 For equipment with recycling systems, the quantity of gases may be two-thirds of that required in subitem 2.11.14.
2.11.15 All pressure, depth, or equivalent indicators must be constructed to be unaffected by ambient conditions, except those designed for such conditions.
2.11.16 All control instruments, indicators, and other accessories must be indelibly and legibly marked in Portuguese regarding their function.
2.11.17 Systems and equipment must be permanently maintained to ensure perfect operation when used.
2.11.18 Diving systems and equipment must include:
a) umbilical, except when using self-contained diving techniques;
b) lifeline, except when:
I. the nature of operations makes its use inconvenient, using an alternative system to maintain diver safety;
II. the working depth is less than 30 meters and one of the submerged divers is already using it.
c) in operations using a diving bell, means to record all intercommunications during pressurization from start to finish on magnetic tape;
d) intercommunication system between divers and the operation supervisor in depths greater than 30 meters, except when using self-contained diving techniques;
e) depth gauge for surface reading in operations deeper than 12 meters, except when using self-contained equipment;
f) system and equipment to safely allow divers to enter and exit the water;
g) normal and emergency lighting system to adequately illuminate the control site and water surface during night dives, except when the nature of operations contraindicates its use;
h) mandatory individual equipment composed of:
I. appropriate suit for each type of dive;
II. reserve breathing mixture supply for emergencies at depths greater than 20 meters;
III. watch for self-contained dives;
IV. knife;
V. individual buoyancy control for work at depths greater than 12 meters or under hazardous conditions, except at depths greater than 50 meters;
VI. protective gloves, except when conditions do not require their use;
VII. waterproof decompression tables for use in self-contained dives;
VIII. inflatable dive vest, depth gauge, snorkel, mask, fins, and adequate weights when using self-contained diving techniques;
IX. flashlight for night dives or dark locations.
2.11.19 All hyperbaric chambers must:
a) be constructed:
I. with viewports allowing all occupants to be clearly visible from the outside;
II. so that all hatches ensure the maintenance of the desired internal pressure;
III. so that all pipes crossing the chamber body have internal and external safety valves near the penetration point;
IV. with internal pressure relief valves operable from the outside in each compartment;
V. with appropriate thermal insulation to protect occupants when using artificial breathing mixtures;
VI. to minimize internal and external fire risks;
VII. to minimize internal noise.
b) be equipped:
I. with safety devices to prevent suction at the internal ends of pipes, allowing depressurization;
II. so that pressure in compartments can be controlled internally and externally;
III. with depth indicators corresponding to internal pressure, inside and at the surface control location;
IV. with a first aid kit containing appropriate medications for typical accidents and instructions for use in the absence of a doctor;
V. with normal and emergency lighting systems in all compartments;
VI. with appropriate tools for possible emergencies;
VII. with adequate decompression tables and emergency procedures;
VIII. with an oxygen partial pressure or percentage analyzer for dives with artificial breathing mixtures;
IX. with automatic equipment graphically and chronologically recording internal pressure variations from pressurization start to decompression or hyperbaric treatment completion.
2.11.20 All surface chambers must:
a) be constructed:
I. with at least two pressure-tight compartments independently pressurizable;
II. with enough space in one compartment to allow two adults to lie down comfortably;
III. with a minimum internal diameter of 1.75 meters, except those already in use in the country at the publication date of this Annex;
IV. with a minimum diameter of 2 meters when used in operations longer than 12 hours, except those already in use in the country at the publication date of this Annex;
V. with compartments allowing the transfer of medications, food, and necessary equipment under pressure from outside to inside and vice versa.
b) be equipped:
I. with appropriate fire-fighting resources in each compartment;
II. with a system capable of providing hyperbaric oxygen therapy to occupants through face masks, with direct exhaust to the outside when using artificial breathing mixtures as the ambient atmosphere;
III. for operations requiring occupancy for more than 12 hours:
A) with an environmental temperature and humidity control system;
B) with a complete sanitary system including a toilet, shower, and sink with hot and cold water.
IV. with a standardized flange by the Directorate of Ports and Coasts (DPC) allowing emergency coupling to different diving bells when using these bells.
2.11.20.1 In compressed air dives, when decompression does not exceed 2 hours or hyperbaric treatment is necessary, chambers with a minimum diameter of 1.20 meters may be used.
2.11.20.2 Chambers exclusively for emergency transport are exempt from the requirements of subitems 2.11.19 and 2.11.20.
2.11.21 All diving bells must:
a) be constructed:
I. with an easily accessible hatch for diver entry and exit;
II. with a coupling hatch allowing easy transfer of divers under pressure to and from the surface chamber;
III. with an internal buoyancy control system operable under any pressure condition, with safety devices preventing accidental operation;
IV. with a safety device preventing internal pipes and oxygen gauges from being subjected to pressures exceeding 8 bars above internal ambient pressure.
b) be equipped:
I. with a standardized flange by the Directorate of Ports and Coasts (DPC) for emergency coupling to any surface chamber;
II. with a main and secondary hoisting system capable of hoisting the bell to the water surface;
III. with resources to maintain the appropriate position, avoiding excessive lateral, vertical, or rotational movements;
IV. with an umbilical incorporating a separate supply line capable of controlling pressurization and decompression from the surface;
V. with external depth indicators;
VI. with thermal protection and external reserve oxygen supply allowing autonomous survival of occupants for at least 24 hours;
VII. with a reserve of artificial breathing mixture exclusively for emergencies;
VIII. with a carbon dioxide partial pressure analyzer;
IX. with appropriate equipment to hoist an unconscious diver into the bell by the remaining diver;
X. with a device allowing easy location for rescue in an emergency.
2.12 Records of Diving Operations
2.12.1 The Record of Diving Operations (ROM) must include:
a) the name of the diving operation contractor;
b) the period during which the operation was conducted;
c) the name or other designation of the diving platform, its location, and the name of its commander or responsible person;
d) the name of the diving supervisor and the period of the operation during which they performed that function;
e) the names of the other members of the diving team and other individuals operating any system or equipment, specifying their respective tasks;
f) arrangements for handling possible emergencies;
g) procedures followed during the diving operation, including the decompression table used;
h) the maximum depth reached by each diver during the operation;
i) for each diver, regarding each dive conducted, the time they left the surface and their bottom time;
j) the type of breathing equipment and the mixture used;
l) the nature of the diving operation;
m) any accidents or injuries suffered by the divers, as well as the occurrence of decompression sickness or other illnesses;
n) details of any emergency occurring during the diving operation and the actions taken;
o) any damage to the equipment used in the diving operation;
p) details of any environmental factors that could affect the operation;
q) any other element of importance for the safety or physical integrity of individuals involved in the operation.
2.12.1.1 Records of intercommunications may only be destroyed 48 hours after the end of the diving operation, provided no accidents, risk situations, or relevant particulars occurred, which in such cases must be recorded in the ROM.
2.12.2 The Diver’s Logbook (LRM) will be approved by the Directorate of Ports and Coasts (DPC) and must include, in addition to the diver’s personal data and records of periodic medical examinations:
a) the name and address of the employer;
b) the date;
c) the name or other designation of the vessel or diving platform from which the diving operation is conducted and its location;
d) the name of the diving supervisor;
e) the maximum depth reached in each dive;
f) for each dive, the time the diver left and returned to the surface and the respective bottom time;
g) when the dive includes time in a hyperbaric chamber, details of any time spent outside the chamber at a different pressure;
h) the type of equipment used and, when applicable, the composition of the Artificial Breathing Mixture used;
i) the work performed in each dive, including the tools used;
j) the decompression tables followed in each dive;
l) any type of accident or injury suffered, as well as the occurrence of decompression sickness or other illnesses;
m) any other element of importance for the diver’s health or physical integrity.
2.13 Decompression and Treatment Tables
2.13.1 The tables used in all diving operations where compressed air is used as the breathing supply, including treatment tables, will be those in Annex C.
2.13.1.1 Other tables may be used, provided they are duly approved by the Directorate of Ports and Coasts (DPC).
2.13.2 Tables for the use of Artificial Breathing Mixtures may only be applied when approved by the Directorate of Ports and Coasts (DPC).
2.14 General Provisions
2.14.1 Submerged or pressurized work is only permitted for workers aged 18 or older.
2.14.2 Diving activity is considered to be of the highest degree of hazardous work.
2.14.3 Non-compliance with the provisions of item 2 – Submerged Work will constitute a grave and imminent risk for the purposes and effects specified in NR-3.
Annex “A” – Psychophysical Standards for Selection of Candidates for Diving Activity
Annex “B” – Psychophysical Standards for Monitoring Personnel in Diving Activity
just trying to find an English version of Norman 15
You can find the unofficial translation of NR15 here