このページは国際安全衛生センターの2008/03/31以前のページです。

Ordinance on Safety and Health of Work under High Pressure
(Revised in terms of the Title March 19, 1977 by Ministry of Labour Ordinance No. 2)
Ministry of Labour Ordinance No. 40, September 30, 1972

Latest Amendments:
Ministry of Health, Labour and Welfare Ordinance No. 171 of July 16, 2001
In Japanese

Chapter III.  Management of Work

Section 3.  Management of Diving Operations

(Time Spent under Water)

Article 27. When the employer has workers engage in diving operations (restricted only to those done at a depth of 10 m or more, same as in this Article), he shall not have the diving workers engage in such a operations in violation of the periods as provided by the provisions given below:

  1. The time spent from when the diving workers start descending until they commence ascending (hereinafter called "time spent under water") shall be limited to the values given below:
    1. In terms of the first shift of diving operations (inclusive of that carried out once per day); the longest time among the times listed in the "Time spend under water" column of Attached Table 2 in accordance with the classification as made in the "Diving depth" column of the said Table on the basis of the depth in which the said shift of diving operation is carried out.
    2. In terms of the second or subsequent shift of diving operation; the times which are available to the reduction of numeric values as noted in the "Gas pressure coefficient in body" column of Attached Table 2 depending upon the classification as made in the "Diving depth" column and the "Time spent under water" column of the said Table on the bases of the diving depth and the time spent under water as used for the previous diving operation, time therefore to decrease gas pressure in the said diving workers as described in item 3 to 5, and the time, as obtainable from Attached Table 3, (hereinafter called "corrected time for diving workers") from the longest of the times listed in the "Time spent under water" column of Attached Table 2 depending upon the classification as made in the "Diving depth" column of the said Table on the basis of the said diving depth, in which the said diving operation is carried out, (corresponding to the one which is deepest, if the diving depth in which the said diving workers operated on the previous shift of diving operations within a day is deeper than that in which the said second or subsequent diving operation has been carried out on the day.) (When the total time for which the said diving workers engaged in diving operations within a day are longer than the time as noted in the "Time spent under water for one day" column of Attached Table 2, depending upon the classification as made in the "Diving depth" column of the said Table on the basis of the deepest depth in which the said diving workers engaged in diving operation on the day, the time is available by further reduction of the difference between the total times and the said times as described in the "Time spent under water for one day" column from the said longest time of those described in the "Time spent under water" column).
  2. When the employer has the diving workers engage in diving operations in more than three shifts per day, and when he makes them engage in the third or subsequent shift of diving operation within a day, the time spent under water for the previous shift in compliance with the provisions of b of the preceding item shall be that which is available by the addition of the time spent under water for the said shift of diving operations and the corrected time for diving workers as mentioned before.
  3. When the employer has diving workers who have already engaged in diving operations on a day, further engage in diving operations on that day, he shall give the said diving workers times which are longer than those listed in the "Time for decreasing gas pressure between shifts" column of Attached Table 2, depending upon the classification as made in the "Diving depth" column and the "Time spent under water" column of the said Table on the basis of the diving depth and time spent under water used for the immediately previous shift of diving operations carried out within a day in the form of the rest periods of time (hereinafter called "time for decreasing gas pressure of diving workers") in order to decrease the gas pressure coefficient in the bodies of the said diving workers after the said diving workers have gone through the said immediately previous shift of diving operations, and for the rest time, the employer shall not make the said diving workers engage in heavy work.
  4. The employer shall give diving workers who have gone through all shifts of the diving operations within a day times which are longer than those described in the "Time for decreasing gas pressure after completion of operation" column of Attached Table 2, depending upon the classification as made in the "Diving depth" column and the "Time spent under water" column of the said Table on the basis of the diving depth and time spent under water used for the final shift of diving operations carried out within a day in the form of time for decreasing gas pressure of the said diving workers after the said diving workers have gone through the final ascension, and shall not make the said diving workers engage in other heavy work.
  5. The provisions of item 2 will apply correspondingly in respect to the time spent under water used for the diving operations as provided for by the preceding two items when the employer gives the said diving workers the second or subsequent shift of time for decreasing gas pressure for diving workers who engage in two shifts or more of diving operations within a day.
(Amounts of Air Feeding and Air Feeding Pressure)
  1. Article 28. When the employer feeds air to the diving workers using air compressors or manual air pumps, the quantities of fed air to each of the diving workers shall be 60 liters or more per minute under the pressure as measured at the diving depth of the said diving operation.
  2. Notwithstanding the preceding articles, when the employer has the diving workers use the pressure regulator, he shall make the said diving workers use air compressors which the quantities of fed air to each diving workers shall be 40 liters or more per minute, and air feeding pressure shall be the value added 0.7 MPa to the pressure of diving depth or more.
(Diving Operations Carried Out with Air Supplied from Air Cylinders)

Article 29. When the employer has diving workers supplied with air from air cylinders, which the said diving workers take with them, (exclusive of the ones for an emergency, same as in Articles 34, 36, and 37), he shall assume the measures given below:

  1. Inform the said diving workers of the existing air-supplying capacity of the air cylinder used for the said diving operation just before the said diving workers start descending.
  2. Station one who observes whether there any mishaps occur with the said diving workers.
(Pressure Regulator)

Article 30. When the employer has the said diving workers receive air from an air cylinder which contains air under a pressure of 1 MPa or more, he shall make the said diving workers use a pressure regulator using a two-step or more decompression system.

(Rates of Ascending, etc.)
  1. Article 31. When the employer has the said diving workers ascend, he shall comply with the provisions given below:
    1. The rates of ascending shall be 10 m/min or less.
    2. When the diving depth reaches that as noted in the "Ascending" column of Attached Table 2, depending upon the classification as made in the "Diving depth" column and the "Time spent under water" column of the said Table on the basis of the diving depth and diving periods of time in or for which the diving operation is carried out at the depth of 10 m or more, he shall stop ascending for a time longer than those described in the said "Ascending" column.
  2. When the employer has the said diving workers engage in diving operations of two shifts or more per day, at the depth of 10 m or more to make the said workers ascend from the locations at which the second or subsequent shift of diving operations within a day was carried out, the provision of item 2 of Article 27 will apply correspondingly in respect to the time spent under water as provided for by item 2 of the preceding paragraph.
(Specific Case of Ascending)
  1. Article 32. When the employer has the said diving workers ascend due to accidents, he is allowed to increase the ascending rates, as provided for by the preceding Article within permitted limits or to reduce the time of stopping ascending, as provided for by the same Article.
  2. When the employer increases the rate of ascending, or reduces the time of stopping ascending in compliance with the provisions of the preceding paragraph, he shall make the said diving workers enter into a recompressing lock just after they ascend to the water's surface, and shall apply compression to the diving workers, up to a pressure equal to that at the deepest depth of the location at which the said shift of diving operation was carried out, or make the said workers descend again down to the deepest location at which the said shift of diving operation was carried out.
  3. In case the employer has the said diving workers enter into the recompressing lock in compliance with the provisions set forth in the preceding paragraph, the provisions of Article 14 will apply correspondingly in respect to the rates of compression applied to the said diving workers.
(Life Line)
  1. Article 33. When the employer has the said diving workers engage in diving operations, he shall provide a life line and make the said diving workers use it in descending and ascending.
  2. The employer shall provide a life line, as described in the preceding paragraph, with a wooden tag or a piece of cloth which indicates the depth at intervals for the depths as described in the "Ascending" column in Attached Table 2.
(Inspection and Repairing of Equipment)
  1. Article 34. When the employer has the said diving workers engage in diving operations, he shall inspect their equipment, as listed in the respective items given below, in accordance with the diving operations set forth in the said respective items before he makes the said diving workers engage in the said diving operation, and shall make repair of the equipment and also necessary measures when he finds a case in which there may occur danger or health impairment to the said diving workers:
    1. In terms of the diving operations using an air compressor or manual air pump for air feeding; diving apparatus, air-feeding pipe, signal ropes, life line and also pressure regulator.
    2. In terms of diving work with an air cylinder (exclusive of an air cylinder which the said diving workers take with them) there from to supply air to the said diving workers; diving apparatus, air feeding pipe, signal ropes, life line or pressure regulator as provided by the Article 30.
    3. In terms of diving operations with air cylinders which supply air to the said diving workers; diving apparatus and pressure regulator as provided by Article 30.
  2. When the employer has the said diving workers engage in diving operations, he shall make inspection of the equipment as listed in the respective items given below in accordance with the types of diving operations as described in the said respective items at least once at every period given in the said respective items, and shall make repair of the said equipment if defective, and shall assume necessary measures when there may be the possibility of hazards or health impairment to the diving workers may occur:
    1. In terms of diving operations therein to supply air to the said diving workers, using an air compressor or manual air pump.
      1. Air compressor or manual air pump: one week.
      2. Air cleaning equipment as provided for by Article 9: one month.
      3. Hydro-barometer as provided by Article 37: one month.
      4. Hydro-watch as provided by Article 37: three months.
      5. Flow-meters as provided by Article 9: six months.
    2. In terms of diving operations therein to receive air supplied from an air cylinder.
      1. Hydro-barometer as provided byArticle 37: one month.
      2. Hydro-watch as provided by Article 37: three months.
      3. Air cylinder: six months.
  3. When the employer makes an inspection of the said equipment or repair of the said equipment or assumes necessary measures in compliance with the preceding two paragraphs, he shall record the results of the inspection or repair when the inspection or repair is carried out, and shall keep a summary record in custody for the period of three years.
(Restrictions on Use of Pure Oxygen)

Article 35. When the employer has diving workers engage in diving operations, he shall not make the said workers inhale pure oxygen.

(Liaison)

Article 36. When the employer has diving workers engage in diving operations with an air compressor or manual air pump thereby to supply air to the said diving workers, or with air cylinders (exclusive of an air cylinder which diving workers might take with them), the employer shall station one liaison (called "liaison" in the following Article) per two diving workers or less to make contact between the said liaison and the diving workers concerned, and shall make the liaison execute the duties given below:

  1. Make contact with the said diving workers to make sure the said divers' descending and ascending are done properly.
  2. Make proper contact with the ones who operate valves or cocks thereby to regulate the air feeding to the said diving workers to supply necessary air to the said diving workers.
  3. Make quick contact with the diving workers when there is a possibility that danger or health impairment of the said diving workers has resulted from accidents involving the damage of air feeding facilities or other accidents.
  4. In terms of diving carried out using the helmet-type diving apparatus, to confirm a sure connection between the said helmets and the pedestal just before a diving worker starts descending.
(Devices to Be Carried by Diving Workers)
  1. Article 37. When the employer has the diving workers engage in diving operations using air compressors or manual air pumps thereby to feed air to the said diving workers, or using air cylinders (exclusive of the ones which the said diving workers take with them) from which the said diving workers receive air to carry out the work, he shall make the said diving workers take with them signal ropes, hydro-watches, hydro-barometers, and sharp-edged knives, provided that the employer is allowed to make the said diving workers refrain from taking with them the said signal ropes, hydro-watches and hydro-barometers when the contact between the said diving workers and liaison can be made through speech communication devices.
  2. When the employer has the diving workers engage in diving operations using air cylinders carried by the said diving workers from which the said diving workers receive the supply of air, he shall make the said diving workers carry with them hydro-watches, hydro-barometers, and sharp-edged knives, and shall make the said diving workers wear a life jacket.
このページの先頭へこのページの先頭へ