|Chapter II. Environmental Control of Office Rooms
Article 2. The employer shall make the air volume of the rooms in which
workers are regularly engaged in their work (hereinafter referred to as
"office rooms"), excluding the volume occupied by facilities
and the space at a height exceeding 4 m from the floor surface, 10 m3 or more per worker.
Article 3. The employer shall make the area of windows and other openings
which can be opened directly to the air at least one-twentieth of the floor
space at all times except when facilities having the function to provide
a sufficient ventilation are installed.
2. The employer shall make the ratio of carbon monoxide and
carbon dioxide in office rooms (ratio of the volume of said gases contained
in the air at one atmospheric pressure and at a temperature of 25°C;
hereinafter the same) fifty-millionths or less, and five thousand-millionths
or less, respectively.
Article 4. The employer shall, when the temperature of office rooms is
10°C or lower, provide heating or take other appropriate measures for
2. The employer shall not, when air-cooling office rooms, make
the temperature of said office rooms too much lower than that of the open
air, except in office rooms where electronic computers, etc., are installed
and operators of said computers, etc., are provided with clothes, etc.,
for keeping warm.
(Adjustment with Air-Conditioning Equipment, etc.)
Article 5. The employer shall, when air-conditioning equipment (equipment
which purifies air, adjusts the temperature, humidity and flow rate of
air and supplies air; hereinafter the same) or mechanical ventilation equipment
(equipment which purifies air, adjusts the flow rate of air and supplies
air; hereinafter the same), that is of the centrally controlled system
type, is installed, adjust such equipment so that the air supplied to office
rooms conforms to the following items:
(1) The quantity of air borne dust (weight of air borne dust
contained in 1 m3 of such air at one atmospheric pressure and at a temperature of 25°C;
hereinafter the same) shall be 0.15 milligram or less.
(2) The ratio of carbon monoxide and carbon dioxide in such
air shall be ten- millionths or less (when it is difficult to supply air
containing carbon monoxide of ten-millionths or less as the open air is
contaminated, twenty- millionths or less) and one thousand-millionths or
2. The employer shall take measures so that the air flowing
into office rooms with the equipment of the preceding paragraph may not
go to particular workers directly and continuously, and shall make the
air current in office rooms 0.5 m per second or less.
3. The employer shall, when air-conditioning equipment of the
centrally controlled system is installed, make an effort to keep the temperature
of office rooms 17°C or higher but 28°C or lower, and the relative
humidity of office rooms 40% percent or more but 70% or less.
Article 6. The employer shall install exhaust pipes, ventilation fans
or other ventilation equipment to office rooms or places where burning
appliances (excluding those which emit very small quantities of heat; hereinafter
the same) are used.
2. The employer shall, when using burning appliances, inspect
such appliances for any abnormality every day.
3. The provisions of paragraph 2 of Article 3, shall apply by analogy to places where the ventilating equipment prescribed
by paragraph 1 is installed.
(Work Environment Measurements, etc.)
Article 7. The employer shall, as to the office rooms of item 5 of Article 21 of the Enforcement Order of the Industrial Safety and Health
Law (Cabinet Order No. 318 of 1972), measure the following items regularly once at least every two months:
(1) Ratio of carbon monoxide and carbon dioxide.
(2) Temperature of office rooms and the open air.
(3) Relative humidity.
2. The employer shall, when making measurements in accordance
with the provisions of the preceding paragraph, record the following items
and shall keep such record for three years:
(1) Date and time of measurements.
(2) Method of measurement.
(3) Locations where measurements were carried out.
(4) Conditions of measurement.
(5) Results of measurements.
(6) Name(s) of person (persons) conducting measurements.
(7) When corrective measures are taken on the basis of
the results of measurements, an outline of such corrective measures.
Article 8. The measurement of the items provided in this Chapter (excluding
the preceding article) which are shown in the left column of the following
table shall be made using the measuring instruments as shown in the right
column of the table or other measuring instruments having the capacity
equal to said measuring instruments.
|Quantity of air borne dust
||Equipment which uses glass fiber filter paper (only filter paper which
has the capacity to collect at least 99.9% of particulates of stearic acid
of 0.3 micrometer) which measures by the weight method air borne dust of
which the relative sedimentation diameter is generally 10 micrometers or
less, or other equipment calibrated using such equipment as the standard.
|Ratio of carbon monoxide
||Carbon monoxide testing equipment using the detection tube method.
|Ratio of carbon dioxide
||Carbon dioxide testing equipment using the detection tube method.
||Thermometer having a calibration for each 0.5°C
||Psychrometer having a calibration for each 0.5 °C
||Anemometer which can measure air currents of 0.2 m per second or more.
||Measurement of the ratio of carbon monoxide and carbon dioxide (only the
ratio which is provided in paragraph 2 of Article 3, temperature, relative
humidity and air current shall be made during the normal working hours
of office rooms at a location 75 cm or higher but 120 cm or lower from
the floor at the center of office rooms.
Article 9. The employer shall inspect mechanical ventilating equipment
for any abnormality when such equipment is first used, is disassembled,
remodeled or repaired, and regularly once at least every two months, record
the results of such inspection and keep such record for three years.
Article 10. The employer shall make the luminous intensity of the working
surface of office rooms conform to the standards shown in the right column
of the following table according to the types of work shown in the left
column of the said table, except those office rooms in which sensitized
materials are handled, or other special work is performed.
|Type of work
||300 luxes or more
||150 luxes or more
||70 luxes or more
2. The employer shall provide offices rooms with lighting and
illumination in the manner that the contrast of light and shade is not
too striking and that workers may not be dazzled.
3. The employer shall inspect the illumination equipment of
office rooms regularly once at least every six months.
(Prevention of Noises and Vibration)
Article 11. The employer shall take measures necessary to prevent the
propagation of those sounds or vibrations which may give workers in office
rooms adverse effects, for example, by providing partitions.
(Prevention of Propagation of Noises)
Article 12. The employer shall, when five or more card punching machines, typewriters
or other office machines generating noises are used simultaneously, provide
an exclusive working room having a ceiling and walls with the capacity
to cut off and absorb sounds to prevent noises from propagating.