Ordinance on Prevention of Hazards Due to Dust

(Measures Relating to Specific Dust Sources)

Article 4.   The employer shall take one of the measures listed in the right column of the following table or equivalent or higher measures for the corresponding specific dust sources listed in the left column of the same table to prevent the dust dispersion in the specific dust sources.

(Ventilating, etc.)

Article 5.   For an indoor workshop in which dusty work other than specific dusty work is performed, the employer shall ventilate with a general ventilation system or take equivalent or higher measures than the above system to reduce dust produced by the dusty work.

Article 6.   For a workshop in a pit in which dusty work other than specific dusty work is operated, the employer shall ventilate with a ventilation device or take equivalent or higher measures than the above device to reduce dust produced by the dusty work.

(Exemption of Application to Temporary Operations of Dusty Work)

Article 7.   Provisions of Article 4 shall not be applied to any case listed in each item of the following, provided that effective personal respiratory protective equipment is used by each worker who is engaged in specific dusty work:

(1)  Where temporary specific dusty work is carried out.

(2)  Where the period of specific dusty work relating to the same specific dust source is short.

(3)  Where the time of specific dusty work relating to the same specific dust source is short.

2.   The preceding two Articles shall not be applied to any case listed in each item of the following, provided that effective respiratory protective equipment is used for each worker who is engaged in the dusty work:

(1)  Where temporary dusty work, other than specific dusty work is carried out.

(2)  Where the period of dusty work other than the specific work done in the same workshop is short.

(3)  Where the time of dusty work other than the specific work done in the same workshop is short. 

(Exemption of Application to Specific Dusty Work Using a Grinding Wheel)

Article 8.   The provisions of Article 4 shall not be applied to any case listed in each item of the following, provided that effective respiratory protective equipment is used for each worker who is engaged in specific dusty work. In this case, the employer shall ventilate the indoor workshop with a general ventilation system and the workshop in a pit with a ventilation device:

(1)  Specific dusty work using a grinding wheel having a diameter of less than 300 mm before the use.

(2)  Specific dusty work using a crusher or pulverizer having a maximum crushing capacity of less than 20 kg/hr.

(3)  Specific dusty work using a screening machine having a screen area of less than 700 cm².

(4)  Specific dusty work using a mixer having an inner volume of less than 18 liters.

(Exemption of Application to the Workshop in which no Facility, etc., Can Be Installed Due to the Structure of the Workshop)

Article 9.   When the Chief of the competent Labour Standards Inspection Office authorizes that it is excessively difficult to take measures stipulated in Article 4 due to the structure of the workshop, nature of the work, etc., in carrying out the specific dusty work, the provisions of Article 4 shall not be applied. In this case, the employer shall let the workers who are engaged in specific dusty work use effective personal respiratory protective equipment and shall ventilate the indoor workshop with a general ventilation system and the workshop in a pit with a ventilation device.

2.   When the employer intends to obtain the authorization stipulated in the preceding paragraph, the Application for Authorizing the Partial Exemption of the Ordinance on Prevention of Hazards Due to Dust (Form No. 2) along with a sketch of the workshop concerned shall be submitted to the Chief of the competent Labour Standards Inspection Office.

3.   When the Chief of the competent Labour Standards Inspection Office receives the Application for Authorizing the Partial Exemption of the Ordinance on Prevention of Hazards Due to Dust stipulated in the preceding paragraph, he shall make a decision whether the authorization stipulated in paragraph 1 shall be granted or not and notify in writing, without delay, the result of the decision to the employer concerned.

4.   When the employer who has been authorized under paragraph 1 alters the contents of the Application for Authorizing the Partial Exemption of the Ordinance on Prevention of Hazards Due to Dust stipulated in paragraph 2 and the sketch of the workshop, he shall submit a report on the change, without delay, to the Chief of the competent Labour Standard Inspection Office.

5.   When the Chief of the competent Labour Standards Inspection Office does not determine that it is extremely difficult to take measures stipulated in Article 4 due to the structure of the workshop, nature of the work, etc., in carrying out the specific dusty work concerning the authorization under paragraph 1, he shall cancel, without delay, the authorization concerned.

(Installation of a Dust Collector)

Article 10.   The employer shall install dust collector for the specific dust sources listed in items 6 through 9 and items 14 and 15 in Attached Table 2 from among the local exhaust ventilation systems stipulated in the provisions of Article 4. (With reference to the specific dust sources (in accordance with the provisions in the preceding three Articles, the specific dust source concerning the specific dusty work to which the provision of Article 4 is not applied shall be excluded) listed in item 7 in Attached Table 2, only limited to the cases where the number of specific dust sources per one workplace is ten or more.

2. The employer shall install dust collector for the specific dust sources listed in items 7, 9, 14 and 15 of Attached Table 2 from among the push-pull type ventilation systems stipulated in the provisions of Article 4. For specific dust sources listed in item 7 of Attached Table 2, this shall be limited to cases where there are ten or more specific dust sources in one workplace (under the provisions of the three preceding Articles, specific dust sources related to specific dusty work where the provisions of Article 4 do not apply shall be excluded.)