Chapter IV.  Prevention of Contamination

(Working Rooms for Handling Radioactive Substances) 

Article 22.  When the employer handles radioactive substances which are not tightly closed, he shall provide a working room used exclusively for the handling of the said radioactive substances, and shall handle the said radioactive substances in the said room, provided that this does not apply in respect to a case in which use is made of radioactive substances by distributing or moving the said radioactive substances in extensive areas for carrying out of investigations into water leakage, epidemiological investigations with insects, investigations into moving statuses in the manufacturing processes of raw materials, etc., and in which use as specified above is temporary, or a case in which mining is made of nuclear raw materials (nuclear raw materials shall be defined as those provided for by item 3 of Article 3 of the Atomic Energy Basic Law (Law No. 186, 1955), same as in the following).

2.  The provisions of paragraph 4 of Article 3 and paragraph 2 of Article 15 shall be applied with necessary modification to the work room where radioactive substances are handled (meaning the work room defined in the preceding paragraph and the exclusive passage for the workers to engage in the work defined in provision of the same paragraph).

(Structures of Working Rooms for Handling Radioactive Substances)

Article 23.  In terms of the portions which may be contaminated with radioactive substances, comprising walls, floors, etc., in the inside of the said working rooms therein to handle radioactive substances, the employer shall provide the said walls, floors, etc., in a structure as provided below:

(1)  The walls, floors, etc., shall be made of materials which are extremely resistant to permeation by gas or fluid, and also which are corrosion-proof.

(2)  The said walls, floors, etc., shall have smoothly finished surfaces.

(3)  The walls, floors, etc., shall be in a structure in which the said walls, floors, etc., have only necessary number of concave-convex portions, and crevices.

(Concentrations of Radioactive Substances in the Air)

 Article 24.  The employer whose employees engage in the mining of nuclear raw materials in mine shall control the average of the daily averages of the concentration of such substance in three months to the level or lower than the level designated by the Minister of Health, Labour and Welfare under paragraph 3 of Article 3.

Article 25.  The employer shall control the three-month average of the weekly average concentration in workplaces other than working rooms for handling radioactive substances and/or the inside of quarries for mining nuclear raw materials to one-tenth or less of the limit designated by the Minister of Health, Labour and Welfare under paragraph 3 of Article 3.

(Facilities to Prevent Dispersion)

Article 26.  When there may occur a case in which dispersion is made of spray or powder of radioactive substances resulting from handling of the said radioactive substances, the employer shall install or provide facilities with boards, curtains, etc., thereby to prevent the said spray or powder of radioactive substances from adhering to the bodies of workers, or clothes, footwear, working clothes, personal protective equipment, etc., which the said workers wear (hereafter called "equipment worn"), provided that this does not apply in respect to a case in which installation of the said facilities are extremely difficult resulting from the conditions under which the said work is being carried out and also a case in which the employer has the said workers concerned wear personal protective equipment as provided for by paragraph 1 of Article 39.

(Tools to Handle Radioactive Substances)

Article 27.  The employer shall post written notices which state the exclusive use of forceps, pincettes, etc., in handling of radioactive substances, and attach the notices to the said forceps, pincettes, etc. In addition, he shall not allow workers concerned to use these tools for other purposes.

2.  When the employer does not use the said forceps, pincettes,, etc., he shall keep the forceps, pincettes, etc., in custody, using tool-storing hanger, boxes, etc., which are of a structure such that easy removal can be made of contaminated radioactive substances and also which are made of materials thereby to enable the said contaminated radioactive substance to be easily removable.

(Measures Assumed when Radioactive Substances Spill, etc.)

Article 28.  When the workplace is contaminated with radioactive substances, either in liquid form or powder form, by means of an accident such as spilling, the employer shall immediately take measures for preventing the spread of the contamination, indicate the area where contamination is likely by putting up warning notices and remove the contaminant until the degree of the contamination is reduced to the limit or less than the limit listed in the Attached Table, providing that the level to which the contamination is to be reduced may be one tenth of the limit listed in the said table where the contamination has occurred in the place other than working rooms for handling radioactive substances.

(Inspection into Contamination in Working Rooms for Handling Radioactive Substances)

Article 29.  The employer shall inspect the ceiling, floor, walls and facilities, etc. of working rooms for handling radioactive substances at least monthly, and, if said objects are found to be contaminated to the levels exceeding the limits listed in the Attached Table, the employer shall remove the contaminant until the levels of the contamination of the said objects are reduced to the limits or below the limits listed in the annexed table.

2.  When the employer has workers clean the said objects to remove the radioactive substances as set forth in the preceding paragraph, he shall use methods thereby to invite no dispersion of radioactive substance dust.

(Inspection of Contamination of Contamination Removing Tools, etc.)

Article 30.  When the removal of the contamination or the cleaning for the objects designated in Article 28 or paragraph 1 of the preceding article is done, the employer shall inspect the tools used for such removal of contamination or cleaning inspected for contamination each time when such contamination removing or cleaning work is done, and, if the tools are found contaminated to levels exceeding the limits listed in the Attached Table, the employer shall prohibit the workers from using such tools until the contamination of the tools is reduced to the levels lower than those listed in the said table.

2.  The employer shall post a written notice which states that the tools have been contaminated with radioactive substances at locations or places where the said devices are kept in custody.

3.  The provision of paragraph 2 of Article 27 shall apply correspondingly in respect to the tools as provided by the paragraph 1.

(Contamination Inspection of Workers Leaving Working Rooms)

Article 31.  The employer shall provide a contamination inspection room at the entrance to working rooms for handling radioactive substances in order to inspect the contamination of workers' bodies and equipment worn carried by the individual workers who are to leave the said working room.

2.  When the levels of the contamination of the workers' bodies and equipment worn carried by the individual workers are found to exceed one tenth of the limits listed in the Attached Table through the inspection, the employer shall not permit the contaminated workers to leave the working room for handling radioactive substance unless the workers go through the following contamination removing requirements:

(1)  Wash the body until the level of contamination is reduced to less than one tenth of the limit designated in the Attached Table, if the body is contaminated.

(2)  Take off or remove equipment worn from their bodies, if such equipment worn are contaminated.

3.  In accordance with instructions as provided by the preceding paragraph, the workers shall wash their bodies or take off or remove their equipment worn from their bodies.

(Inspection of Contamination of Goods Taken out of Working Rooms)

Article 32.  In terms of goods which the workers take with them out of the working rooms for handling radioactive substances, the employer shall inspect the status of contamination of the said goods with radioactive substances at contamination inspection room as described in the paragraph 1 of the preceding Article when the workers take the goods with them leaving the said working rooms.

2.  Both the employer and its employees shall not be allowed to bring out the goods found to be contaminated respectively to the levels exceeding one tenth of the limit designated in the Attached Table through the inspection conforming to the provision of the preceding paragraph except where such contaminated goods are to be carried to the contamination removing facilities, contaminated objects storage facilities, contaminated objects disposal facilities or other working room for handling radioactive substances in which they use the containers as provided for by the text of paragraph 1 of Article 37 or assume measures for the proviso of the same paragraph.

(Storage Facilities)

Article 33.  The employer intending to store the objects found to be contaminated respectively to the level exceeding one tenth of the limit designated in the Attached Table (hereinafter referred to as "contaminated objects") shall store the contaminated object in such a storage facility separated from external circumstances, and also which are provided with a locking mechanism and other closing devices or tools at the portions which lead to the outside of the said facilities such as doors, covers, etc.

2.  The employer shall post notices which state the existence of the storing facilities at places from which the notices can easily been seen outside the said storage facilities.

3.  The provision of paragraph 4 of Article 3 shall be applicable with necessary modification to the storage facilities set forth in paragraph 1.

(Facilities for Exhausted Air or Fluid)

Article 34.  When the employer draws exhausted air or fluid out of working rooms for handling radioactive substances, stores the said exhausted air or fluid, or purifies the said exhausted air or fluid, he shall draw, store or purify the said exhausted air or fluid in the facilities in a structure in which the facilities have no fear that there may occur discharge of air or fluid from the said facilities, also in which the facilities are made of materials which are extremely resistant to corrosion and impermeable by the said discharged fluid.

2.  The provisions of paragraph 2 of the proceeding Article shall apply correspondingly in respect to the facilities as set forth in the storage and disposal facilities set forth in the proceeding paragraph.

(Incinerators)

Article 35.  When the employer incinerates radioactive substances or contaminated objects, he shall use the incinerator in a structure in which there is no possibility that leakage or dispersion may take place of air or ashes, respectively, from the said incinerator.

2.  The provision of paragraph 2 of Article 33 shall be applicable with necessary modification to the incinerator set forth in the preceding paragraph.

(Disposal-by-Storage Facilities) 

Article 36.  When the employer dispose radioactive substances or contaminated objects by storage, he shall do the said disposal- by-storage in the said facilities, separated from external circumstances, and also which are provided with a locking mechanism and other closing devices or tools at the portions which lead to the outside of the said facilities such as doors, covers, etc.

2.  The provisions of paragraph 4 of Article 3 and paragraph 2 of Article 33 are respectively applicable with necessary modifications to the disposal-by-storage facilities set forth in the preceding paragraph.

(Containers)

Article 37.  When the employer stores or keeps radioactive substances, or carries radioactive substances or contaminated objects, stores these substances to dispose, or stores temporarily these substances for a while to dispose, he shall use containers, provided that this does not apply in respect to a case in which it is extremely difficult to store these substances in the said containers, he assumes effective measures thereby to shield external radiation, to prevent spreading of contamination with radioactive substances, or carries radioactive substances in working rooms for handling radioactive substances.

2.  When using the containers designated in the preceding paragraph for the purposes listed in the left column of the following table, the employer shall make sure that each of such containers has the structure correspondingly listed in the right column of the same table according to the classified uses.

3.  The employer shall put notices on the containers as described in paragraph 1, which say that the containers are those therein to contain radioactive substances or contaminated objects.

4.  The employer shall indicate the items, as given below, on the containers in which to store, keep or carry the substances, or store temporarily the substances for a while to dispose of the said substances.

(1)  Types of radioactive substances and classification of gas, liquid or solid of the radioactive substances.

(2)  Types of radioisotopes contained in the radioactive substances and quantities of the radioisotopes.

(Personal Protective Equipment)

Article 38.  When the employer whose workers engage in the work in the area designated in the provision of Article 28 or emergency work in which the workers may inhale the air contaminated to the level exceeding that designated by the Minister of Health, Labour and Welfare under paragraph 3 of Article 3, such employer shall provide the effective personal respiratory protective equipment depend on the level of contamination such as the dust masks, gas masks, hose masks, oxygen breathing apparatus, etc., to the workers.

2.  While the workers are engaging in the work as provided for by the preceding paragraph, they shall use the personal protective equipment described in the same paragraph.

Article 39.  The employer whose workers engage in the work in which the workers may be contaminated to the level exceeding one tenth of the limit designated in the Attached Table shall provide effective protective clothes, gloves and shoes to the workers.

2.  While the workers engage in the work as provided by the preceding paragraph, they shall use the personal protective equipment described in the same paragraph.

(Working Clothes)

Article 40.  When the employer has workers engage in the work in the working rooms for handling radioactive substances, he shall provide working clothes used exclusively for work in the said rooms, and shall have the workers use the said working clothes when the workers engage in the said work.

(Decontamination of Personal Protective Equipment, etc.)

Article 41.  When the personal protective equipment or working clothes to be used conforming to the provisions of the preceding three articles are found to be contaminated to the levels exceeding those designated in the Attached Table (to one tenth of the limit designated in the same table for the parts of the personal protective equipment or working clothes which directly come into contact with the bodies of the workers, which applies hereinafter in this article), the employer shall not allow the workers to use such objects unless they are decontaminated by cleaning, etc., to the levels less than the limit designated in the said table.

(Prohibition of Smoking, etc.)

Article 41-2.  The employer shall prohibit workers from smoking, drinking or eating in working rooms for handling radioactive substances or any other work room where there is a possibility that workers may inhale or take in a radioactive substance and put up warning notices to such effect in easily visible locations in the work rooms concerned.

2.  The workers shall not smoke, drink or eat in the work rooms specified in the preceding paragraph.