The Role of Work Environment Control for the Prevention of
Occupational Diseases in Japan, from the viewpoint of theexperiences of Japan
Revised in August 2007
Masayoshi Karasawa,
Special Adviser,
Japan Association for Working Environment Measurement (JAWE)
Licensed Industrial Hygiene Consultant
Member of the Board of Directors of International Occupational Hygiene
Association (IOHA)
1.

Occurrence of occupational diseases in Japan in recent decades

The occurrence of occupational diseases in Japan fell from 18,000 per year in the late 1970s
to an average of 13-14,000 in the 1980s. This number dropped further to 7,609 in 2004. Since
then the figure has increased again from 8,226 in 2005 to 8,369 in 2006, respectively. (see Fig.
1；Source: Survey of Occupational diseases (Ministry of Health, Labour and Welfare)1Fig. 1 Transition of number of workers suffering from occupational diseases (accompanying absence of 4 daysor more), by year

20,00020,544
18,644 18,449
16,70515,000

15,48015,147

14,588 14,547
12,510 12,523 12,464
11,415

10,00011,951
10,8429,630 9,915

9,230 9,250
8,557 8,574

7,817 8,083 7,984

7,502

8,055

7,609

8,2268,369

5,000

0
19
79
19
80
19
81
19
82
19
83
19
84
19
85
19
86
19
87
19
88
19
89
19
90
19
91
19
92
19
93
19
94
19
95
19
96
19
97
19
98
19
99
20
00
20
01
20
02
20
03
2,0
04
20
05
20
06

number of workers suffering from occupational diseases

25,0002

calemdar year

Fig.2 Occupational Diseases by Type 2005
Other diseases

440

number of dseases

Pneumoconiosis and related
complications

767

Diseases due to chemical
substances

306

Diseases due to working
mode

425

Diseases due to physicalfactors459

Diseases due to injuries

5,829

0

1,000

2,000

3,000
3

4,000

Type of Diseases

5,000

6,000

7,000

As shown in Fig. 2, injuries (5,329persons) were the number one cause of occupational diseases in
2004, followed by pneumoconiosis and related complications (767 persons), diseases due tophysical factors (459 persons), diseases due to working mode (425 persons), and diseases due tochemical substances (306 persons). In addition, 440 persons suffered from health problems
stemming from other diseases.
Source: Survey of Occupational diseases and Survey on the results of Pneumoconiosis Control (Ministry of Health,Labour and Welfare)Notes: 1. “physical factors” means noise, extreme temperatures, etc
2. “working mode” means heavy lifting, repetitive stress, etc.
3. The figure for “Pneumoconiosis and related complications” represents the sum of persons suffering fromcases classed as Pneumoconiosis Management Classification 4, and the number of persons suffering frompneumoconiosis-related
complications(including
casesof“application
atwill”).

4

Fig. 3 shows the annual figures since 1983 for the number of occupational diseases stemming fromthe four most common causes (injuries; pneumoconiosis and related complications; unhealthy
physical factors in the environment; and unhealthy physical exertion).
We can see that there were large numbers of occupational diseases in Japan in the 1970s and 80s.
Since then, these numbers have generally been falling thanks to measures that the Japanese
government and companies have taken to improve management of the work environment.
The occurrence of pneumoconiosis, although both the number and ratio of newly detectedpneumoconiosis of examined workers (defined as persons who have been tested forpneumoconiosis and been placed in Pneumoconiosis Management Classification 2 or higher) haveboth fallen, has not been greatly reduced. And also, the number of persons suffering frompneumoconiosis or related complications (defined as persons who have been placed inPneumoconiosis Management Classification 4, and persons who have been diagnosed as sufferingfrom pneumoconiosis-related complications) has changed very little (as shown in Fig. 4).
However, I would like to say, thanks to the development of the countermeasures shown in Fig.4,
both the number and ratio of newly detected pneumoconiosis of examined workers have both fallen
considerably. These countermeasures contribute to the improvement of the prevention of
Pneumoconiosis.
And, Occupational diseases due to chemical substances remain almost unchanged, totalling over
300 persons per year.

5Fig. 3

Occupational diseases in Japan since 1983

Diseases due toinjuries

Pneumoconiosis andrelated complications
(A)
(B)

6

Fig. 3 (continued)
number of occupational diseases by type

7,000
6,000
5,000
Diseases due to injuries
Pneumoconiosis and related complications
A problems steming from physical factors
B problems steming from working modes

4,000
3,000
2,000
1,000
0
Diseases due to injuries
Pneumoconiosis and related
complications
A problems steming from physicalfactors
B problems steming from working
modes

1,999
5,388
1,276

2,000
5,405
1,180

2,001
5,652
982

2,002
5,277
956

2,003
5,861
856

2,004
5,370
814

2,005
5,829
767

395

461

517

443

447

513

459

357

438

381

346

393

368

425

calendar year

Note:
“B”

“A” shows problems stemming from physical factors.
shows
problems
stemming

7

fromworking

formats.

Years
1950

1955

1960

1965

1970

1975

1980

1985

Numberof
ofWorkers
Workers
Number2000

50

ex amin d n um be r s o f
pn e u mo c o n is isme dic al e xam ina t io n40

nu mbe r o f d e t e c te dpn e u moc o n io sis

10000

1995

60

n u m ber o f t o t al
wo r ke r s e xp o se d t o
dus t

1000001990

n u mbe r o f th e n e wly
d e t e c te dpn e u moc o n io sis

30r at e o f d e t e c te dpn e u moc o n io sis

20

1000

Rate of detected pneumoconiosis

1945
1000000

10100

The 1st Administrative Note on
limit of Dust Concentration in
1948
Special Law on silicosis etc in 1955
The 1st Administrative Note of dust measurement in 1958
Pneumoconiosis Law in 1960

0Working Environment Evaluation Standard in 1988
Administrative Note No.69 in 1984
1st Report of the Expert Council in 1980
Ordinance on Prevention of Hazardous due to Dust in 1979
The revision of Pneumoconiosis Law in 1977
Working Environment Measurement Standard in 1976
Working Environment Measurement Law in 1975

Fig.4 Result of medical examinations for pneumoconiosis

82.

System for work environment control
With regard to the prevention of occupational diseases due to toxic chemical substances, andprevention of pneumoconiosis and related complications, the system for work environment
control is as described below in Table 1.

9Table 1 System for Work Environment Control in Japan(1)

Identification of the toxicity of chemical substances used as raw materials,
determination of the degree of exposure of workers to these substances, andassessment of the expected impact upon their health.
(2) Halting the use of toxic raw materials. Switch to less toxic raw materials.
(3) Improvement of production processes and work methods in order to prevent therelease of toxic substances.
(4) Adoption of airtight, automated, and/or remote control production equipment.
Isolation of toxic processes(5) Use of local exhaust ventilation systems (including push-pull type exhaust
ventilation equipment) in order to minimize worker exposure to toxic substances.
(6) Limitation of the use of general ventilation systems to certain specific conditions inorder to lower the concentration of toxic substances in such systems.
(7) Measurement of work environments in order to check the effectiveness of work
environment measurement.
(8) Evaluation of the results of work environment measurements(9) Installation of equipment required resolving any problems that may be identified bya work environment measurement. (Installation of local exhaust ventilation systems[including push-pull type exhaust ventilation equipment], and general ventilation
systems, when the work environment allows the use of such systems.)(10) Control of work methods. (Use of personal protective equipment when there is a riskof exposure to high concentrations of toxic substances; limitation of time spentworking under such conditions; etc.)(11) Health management (special medical examinations on a regularly scheduled basis
for persons engaged in work involving exposure to toxic substances)(12) Occupational Health education for workers (training in various subjects, including:proper work methods for persons working in a toxic environment; health effects of
toxic substances; maintenance of local exhaust ventilation systems [including pushpull type exhaust ventilation equipment] and general ventilation systems; etc.)

3.

Identification of the toxicity of chemical substances used as raw materials, determination of
the tolerance of workers to these substances, and assessment of the expected impact upon
their health

I would like to tell you of how I learned from personal experience about the importance of item (1)in Table 1 above.
In the autumn of 1995, back when I was working at the Ministry of Labour, as the Director of the
Chemical Substances Investigation Division of the Industrial Safety and Health Department, inside
the Labour Standards Bureau, we received a very alarming piece of news from Japanese experts
who had been sent to Korea to work with the Korean Industrial Safety Corporation (KISCO). At a
Korean electronics factory that was using a Japanese-made cleaning compound containing 2bromopropane (see Fig.5) as the main ingredient, both male and female workers were experiencing
10serious health problems. Women experienced grave suppression of menstruation and showed a dropin their thrombocyte counts, while men had reduced sperm counts.
Fig.5

Chemical structure of 2-bromopropane
Ｂｒ｜
CＨ3―CＨ―CＨ3

We immediately took a number of urgent measures to determine the nature of the problem. We
called in various parties (including the Japanese manufacturer of the cleaning compound, Japanesechemical manufacturers that produced the 2-bromopropane domestically, and trading companies
that imported 2-bromopropane from abroad) to question them about the situation. In addition, we
also researched the available scientific literature on 2-bromopropane and conducted a survey ofcompanies in Japan that were using cleaning compounds based on 2-bromopropane as the main
ingredient. Our findings can be summarized in the following five points.
(1) The cleaning compound in question had been developed by its Japanese manufacturer as a
substitute for another popular product that was due to be phased out because it contained CFC113, a chemical that contributes to destruction of the ozone layer.
(2) It had already been reported in the scientific literature that 2-bromopropane: (a) was irritating to
the eyes, lungs, and skin; (b) had an anesthetic effect; and (c) had a toxic effect upon the liver,kidneys, and heart. At the time of the product’s development, however, nothing was known of
its effect upon the reproductive system or the blood.
(3) Among the Japanese chemical manufacturers that produced 2-bromopropane domestically, one
company provided clients with a warning not to use 2-bromopropane in cleaning compounds
and other products meant to be used in an open environment (where there is a strong risk ofworker exposure). This company explained that the reason for this warning was that 2bromopropane contained bromine, and that its toxicity had not been fully verified. Apart fromthis one company, however, Japanese chemical manufacturers that made 2-bromopropane
provided clients with no such warning, nor did any of the trading companies that imported it.
I believe that the company that provided its clients with a warning regarding the possible
toxicity of 2-bromopropane deserves to be greatly lauded for its action.
(4) A study carried out in South Korea concluded that the chances were very high that the
reproductive irregularities and other health problems experienced by the South Korean workers
were very probably the result of exposure to 2-bromopropane.
(5) Japanese workplaces using cleaning compounds based on 2-bromopropane as the main
ingredient had not reported any unusual occurrence of health problems.
In December 1995, the Chemical Substances Investigative Division sent out notices to Japanese
11industrial organizations and all of Japan’s Prefectural Labour Standards Bureau calling on them totake urgent action to prevent workers from being exposed to 2-bromopropane. In our notices we
explained that there was a very high probability that exposure to 2-bromopropane can result inserious reproductive problems and other health disorders. Our division also informed KISCO in
Korea of the measures that had been taken to address the problem in Japan.
4. Carrying out appropriate the work environment measurement
The concept of work environment control was first incorporated into occupational safety and healthlegislation in Japan when the Industrial Safety and Health Law was enacted in 1972. Article 65 ofthis law requires employers to carry out work environment measurement in order to facilitate work
environment control. An early precursor to this legislation had already appeared, however, in theform of Labour Standards Bureau Issuance No. 1178, 1948. Prior to passage of the Industrial Safety
and Health Law, Article 42 of the Labour Standards Law already required companies to take steps
to prevent work environments from having an adverse effect on the health of their employees. The
Ordinance on the Prevention of Organic Solvent Poisoning, which was enacted in 1960, wasintended as a means of helping to ensure the achievement of this goal. The Ordinance requires theuse of local exhaust ventilation systems where certain organic solvents are handled, and it specifies
the controlled wind velocity at which these ventilators must be set to eliminate organic solvent fromthe work environment. In order to ascertain that the local exhaust ventilation systems in a given
workplace are functioning effectively, companies are further required to install detector tubes.
However, the Ordinance did not mandate the achievement of specific numerical targets, thus thisOrdinance did not constitute the basis of “work environment control” as we understand the term
today.
The Ordinance on the Prevention of Organic Solvent Poisoning was passed in response to a rash ofhealth problems suffered by workers exposed to benzene in connection with the home-based
production of “Hep-sandals.” (This name derives from Audrey Hepburn, who wore sandals in theAmerican movie “Roman Holiday” which became a huge hit product in Japan.)

12

Audrey Hepburnin “Roman Holiday”

The Ordinance required the use of work environment measurements in workplaces where certain
organic solvents were used.
After this wave of benzene poisoning incidents, the manufacture of rubber cement containing
benzene was prohibited in Japan in November 1959. Since 1975 benzene has been regulated as a
carcinogenic substance, and its use in organic solvents is in principle prohibited.
With the 1971 passage of the Ordinance on Prevention of Hazards due to Specified Chemical
Substances, the regulatory system changed. The regulation method based on the number of tasks,
which had formerly been used, was abandoned in favour of a system based on the concept of work
environment control, in which toxic chemical substances were subject to “concentration limits.”
Article 65 of the Industrial Safety and Health Law of 1972 required companies to carry out work
environment measurements, and to adopt work environment control solutions based on the resultsof these measurements. Further legislation designed to ensure that companies would address
problems in a comprehensive manner did not come along until 1975, when this need was addressedby the Working Environment Measurement Law, as well as by Article 65 of the Industrial Safety
and Health Law after the latter was amended in that same year. With regard to indoor workplaces
where workers are exposed to toxic substances (as well as other workplaces where workers are
exposed to significant health risks), these new items of legislation required that employers carry out
regularly scheduled measurements (in principle, at least once every six months), in accordance withthe provisions of the Minister of Labour’s Work Environment Measurement Standards. Since April
30, 1977 the law has required that work environment measurements be carried out by either a work
environment measurement expert, or by a registered work environment measurement agency hiredfrom outside the company.
The requirement to have work environment measurements carried out (either by a work
13

environment measurement expert or a registered work environment measurement agency) ensured
that these measurements would be carried out in a scientific manner by properly qualified experts
using proper design, sampling, and assay techniques. (Article 2, Section 4 of the Industrial Safety
and Health Law requires that companies “carry out design, sampling, and assays (including
analysis) to determine the safety of the air and other elements of the work environment.”) This newlegislation brought considerable progress in the field of work environment measurement.
I would like to emphasize one key difference between the way work environment measurement iscarried out in Japan and in the West. Work environment measurement in Japan is used as a means ofassessing the state of work environment control and, when the results of the assessment indicate anecessity, of devising measures to improve the work environment. In the West, on the other hand,the degree of exposure of individual workers is often measured; but we do little of this in Japan.
5.

Work environment measurement in JapanThe main purpose of work environment measurements is to obtain an accurate understanding of theworking conditions of employees who work in toxic environments, so as to determine what
equipment needs to be installed in order to improve the work environment. A work environment
measurement must be objective and accurate.
For this reason, the Minister of Labour’s Work Environment Measurement Standards include
stipulations regarding the following aspects of work environment measurements:(1) The method of defining what constitutes a unitary workplace(2) The method of determining what must be measured(3) The method of determining the timing and duration of measurements(4) The type and performance of analysis equipment to be used for carrying out measurements
6.

Evaluating the results of work environment measurements

With regard to evaluation of the results of work environment measurements, the government has
issued administrative guidance for the past 15 years urging companies to carry out their evaluationsin accordance with a Labour Standards Bureau circular issued in February 1984. In a further effort
to ensure that companies would evaluate the results of work environment measurements in an
effective and appropriate manner, and to ensure that companies would pursue whatever measuresthat such evaluations revealed to be necessary, the Industrial Safety and Health Law was amended
in February 1988 (a new clause was added to Article 65-2). The amended law required companies
to take the results of work environment measurements as the basis in carrying out work
environment measurement evaluations in accordance with the provisions of the Minister ofLabour’s Work Environment Measurement Standards. Large numbers of workplaces throughout
Japan now carry out systematic work environment management in accordance with therequirements of the Work Environment Measurement Evaluation Standards.
7.

How the results of work environment measurements are evaluated in Japan, and postevaluation follow-up measures14

After the results of work environment measurements are evaluated, the work environment inquestion is classed into one of three categories (Control Classification 1, Control Classification 2,
and Control Classification 3), as required by the Minister of Labour’s Work Environment
Measurement Evaluation Standards (Table 2). The Standards serve as an indicator of the quality (orlack thereof) of the work environment management at a given workplace, and are used forevaluating workplaces where employees are exposed to dust, specified chemical substances, lead,and organic solvents.
Fig.6 provides a flow chart that summarizes the content of what I have described above (workenvironment measurement; evaluation of the results thereof; the type of working conditions
corresponding to the three control classifications; and the measures that must be taken to address
problems).
Evaluations are carried out in accordance with the provisions of the Work Environment
Measurement Evaluation Standards (table 2). This process is summarized in Fig. 6 as well as Table
3.

15

Table 2

Working Environment Evaluation Standards
Ministry of Labour Notification No. 79 of September 1, 1988
Latest Amendments:
Ministry of Health, Labour and Welfare Notification No.369 of April 1, 2005

(Scope)Article 1. This notification shall apply to workshops listed in items l, 7, 8 and 10
metallic materials or carbon in the air of such indoor workplaces prescribed in item
1, Article 21, the Enforcement Order of Industrial Safety and Health Law (Cabinet
Order No. 318, 1972, hereinafter referred to as the Cabinet Order) shall bemeasured in accordance with the provisions specified in the following :(Evaluation of the Results of the Measurement)
Article 2. Evaluation of the results of the working environment measurement
prescribed in paragraph 1 of Article 65-2 of the Industrial Safety and Health Law
shall be carried out by classifying into Control Class 1 to Control Class 3 as listed in
the right column of the following table, according to the case in following items, foreach unit work area, prescribed in item 1 of paragraph 1 of Article 2 of Working
Environment Measurement Standards (Ministry of Labour Notification No. 46,
1976), hereinafter the same.
(1) In cases where only A Sampling (sampling carried out according to items 1 to 2of paragraph 1 of Article 2 of the Working Environment Measurement Standards,
including cases where the same provisions are applied mutatis mutandis inparagraph 4 of Article 10, paragraph 2 of Article 11 or paragraph 4 of Article 13,
hereinafter the same), has been carried out.

Control Class

2 of paragraph 1 of Article 2 of the Working Environment
Measurementlevel for the substances to be measured as prescribed in
Attached Table

Control Class I

1st evaluation value is less than administrative control level

1st evaluation value is equal to or more than administrative
control level
Control Class II and 2nd evaluation value is equal to or less than administrative
control
level
Control Class III 2nd evaluation value is more than administrative control level(2) In cases where both A Sampling and B Sampling (sampling carried out with theprovision of item 2-2 of paragraph 1 of Article 2 of the Working Environment
Measurement Standards, including cases where the same provisions are appliedmutatis mutandis in paragraph 4 of Article 10, paragraph 2 of Article 11 orparagraph 4 of Article 13, hereinafter the same), have been carried out.
16

Control Class

Result of comparison of evaluation value or measured value of B
sampling andadministrative control level for the substances to be measured asprescribed in Attached Table .

Control Class I

Both 1st evaluation value and measured value of B sampling (incases where B
sampling was carried out at more than 2 sampling points, thelargest value
shall be adopted, hereinafter the same) are less thanadministrative control
level

2nd evaluation value is equal to or less than administrative
control level, andControl Class II measured value of B sampling is equal to or less than 1.5 times
administrative
control level (excluding cases classified as Control Class l)
2nd evaluation value is more than administrative control Level, or
measuredControl Class III
value of B sampling is more than 1.5 times administrative control
level
2. In a unit work area which has sampling points where the concentration ofsubstances to be measured was less than the lower limit value of the sampling
method or the analysis method adopted for the measurement, the lower limit
value should be used as the measured value of the point to carry out theclassification of the preceding paragraph.
3. In a unit work area which has sampling points where the concentration ofsubstances to be measured was less than one tenth of Administrative Control
Level, classification of paragraph 1 may carried out by using one tenth of the
Administrative Control Level as the measured value of the measuring point.
4. In a unit work area pertaining to a mixture including more than 2 organic solvents
stated in items 1 to 47 of Attached Table 6-2 of the Enforcement Order ofIndustrial Safety and Health Law, classification of paragraph 1 should be carriedout by using a converted value calculated by the following formula for eachsampling point. In this case, I shall be used as the Administrative Control Level.

(Calculation of Evaluation Value)
Article 3. 1st evaluation value and 2nd evaluation value of paragraph 1 of preceding
Article should be calculated by the following formulae.

17

2. Notwithstanding the provision of' the preceding paragraph, in cases whenmeasurement was conducted for 2 successive workdays (in case there wasrational reason why the measurement could not be conducted for 2 successive
workdays, 2 workdays with the minimum interval), 1st evaluation value and 2nd
evaluation value can be calculated by the following formulae.

18

Attached Table
Kinds of substances

Administrative Control Level

3 .0
0.59Q + 1
E administrative control level(mg/m3)Q content of free silica(percent)E=

1. Dust of sand and stones, rocks,
ores(minerals), metallic materials or carbon

2. Acrylamide

0.3 mg/m

3. Acrylonitrile

2 ppm

3

3

4. Alkyl mercury compounds (restricted tothe substances in which alkyl radicals are
methyl or ethyl radicals)

0.01 mg/m as mercury

5. Ethylenimine

0.5 ppm

6. Ethylene oxide

1 ppm

7. Vinyl chloride

2 ppm

8. Chlorine

0.5 ppm

9. Chlorodiphenyl (otherwise known as PCB)

0.1 mg/m

3

3

10. Cadmium and its compounds

0.05 mg/m as cadmium

11. Chromic acid and its salts

0.05 mg/m as chromium

12. Vanadium pentoxide

0.03 mg/m as vanadium

3

3

3

13. Coaltar

0.2 mg/m as benzene solubility

13-2 Arsenic trioxide

0.003mg/m3 as Arsenic

14. Potassium cyanide

3mg/m as cyanogen3

15. Hydrogen cyanide

3 ppm

16. Sodium cyanide

3

3 mg/m as cyanogen17. 3,3' -Dichloro-4,4' -diamino diphenyl
methane0.005 mg/m

18. Methyl bromide

3

5 ppm
3

19. Dichromic acid and its salts

0.05 mg/m as chromium

20. Mercury and its inorganic compounds(excluding mercury sulfide)

0.025 mg/m as mercury

3

21.Tolylene diisocyanate

0.005 ppm

22. Nickel carbonyl

0.001 ppm

23. Nitroglycol

0.05 ppm

24. p-nitro chlorobenzene

0.6mg/m

3

25. Hydrogen fluoride

2 ppm

26. ß-Propio lactone

0.5 ppm
3

27. Beryllium and its compounds

0.002 mg/m as beryllium

28. Benzene

1ppm
3

29. Pentachlorophenol (otherwise known as
PCP) and its sodium salts

0.5 mg/m as penta chlorophenol

30. Manganese and its compounds (excluding
basic manganese oxide)

0.2mg/m as manganese

3

31. Methyl iodide

2 ppm
19

32. Hydrogen sulfide

5 ppm

33. Dimethyl sulfate

0.1 ppm333-2 Asbestos

0.15 F/cm as fibers longer than 5 µm
334. Lead and its compounds

0.05mg/m as lead

35. Acetone

500 ppm

36. Isobutyl alcohol

50 ppm

37. Isopropyl alcohol

200 ppm

38. Isopentyl alcohol (otherwise known as
isoamyl alcohol)

100 ppm

39. Ethyl ether

400 ppm

40. Ethyleneglycol monoethyl ether (otherwise
known as cellosolve)

5 ppm

41. Ethyleneglycol monoethyl ether acetate(otherwise known as cellosolve acetate)

5 ppm

42. Ethyleneglycol mono-n-butyl ether(otherwise known as butyl cellosolve)

25 ppm

43. Ethyleneglycol monomethyl ether(otherwise known as methyl cellosolve))

5 ppm

44. o-Dichlorobenzene

25 ppm

45. Xylene

50 ppm46. Cresol

5 ppm

47. Chlorobenzene

10 ppm

48. Chloroform

10 ppm

49. Isobutyl acetate

150 ppm

50. Isopropyl acetate

100 ppm

51. Isopentyl acetate (otherwise known as
isoamyl acetate)

100 ppm

52. Ethyl acetate

200 ppm

53. n-Butyl acetate

150 ppm

54. n-Propyl acetate

200 ppm

55. n-Pentyl acetate (otherwise known as namyl acetate)

100 ppm

56. Methyl acetate

200 ppm

57. Carbon tetrachloride

5 ppm

58. Cyclohexanol

25 ppm59. Cyclohexanone

25 ppm

60. 1,4-Dioxane

10 ppm61. 1,2-Dichloroethane (otherwise known as
ethylene dichloride)

10 ppm62. 1,2-Dichloroethylene (otherwise known asacetylene dichloride)

150 ppm

63. Dichloromethane (otherwise known as
methylene dichloride)

50 ppm

64. N,N-Dimethylformamide

10 ppm

65. Styrene

20 ppm

66. 1,1,2,2-Tetrachloroethane (otherwise
known as tetrachloroacetylene)

1 ppm

67. Tetrachloroethylene (otherwise known as

50 ppm20

perchloroethylene)
68. Tetrahydrofuran

200 ppm

69. 1,1,1-Trichloroethane

200 ppm

70. Trichloroethylene

25 ppm

71. Toluene

50 ppm

72. Carbon disulfide

10 ppm

73. n-Hexane

40 ppm

74. 1-Butanol

25 ppm75. 2-Butanol

100 ppm

76. Methanol

200 ppm

77. Methyl isobutyl ketone

50 ppm

78. Methyl ethyl ketone

200 ppm

79. Methyl cyclohexanol

50 ppm

80. Methyl cyclohexanone

50 ppm

81.Methyl n-butyl ketone

5 ppm

Note; These data mentioned above means the concentrations at 25 centigrade as well as1013 hectopascal.

21

Fig.6Work environment measurement flow chart
Define what constitutes a unitary workplace.

Determine the date for measurement

Determine measurement conditions.

Determine the points to be measured.

Determine measurement procedures.

Measurement method A

Measurement method B

Calculate the geometrical mean value and geometrical standard deviation.

Calculate assessment value 1 and assessment value 2.

Determine control classifications on the basis of the Work Environment Measurement Evaluation Standards.

Control Classification 1

Control Classification 2

Control Classification 3

The concentration of
airborne toxicants inalmost all (95% ormore) of the work
environments in theunitary workplace does
not exceed control
concentration.

The average
concentration of
airborne toxicants forthe unitary workplace
as a whole does notexceed control
concentration.

The average
concentration of
airborne toxicants forthe unitary workplace
as a whole exceeds
control concentration.

• Provide employeeswith dust respirator.
• Devise necessary
measures to safeguard
employee health.

Implement the current work
environment control programon an ongoing basis.

Inspect facilities, equipment, production processes, and work
methods. Based on the results of this inspection, takenecessary steps to improve the work environment.

22

Table 3 Control Class, Control Level and Measures to be taken.
Control Class Ⅲ
Control Class Ⅱ
Control Class Ⅰ

2nd control level
1st control level(1) Condition and Measures Shall Be Taken for Each Control Class
Evaluation and Improvement of Working Environment

Control Class

Condition of working area
Concentration of airborne toxic
Substances at almost (more thanControl Class Ⅰ 95 ％ ) points in a unit work area
does not exceed the administrative
control level
Mean concentration of airborne
Toxic does not exceed theadministrative control level
Control Class Ⅱ

Measures to be taken
Continue the current working
environment control to keep thepresent condition

Endeavour to take necessary
measuresforworkingenvironment improvement, basedon the result of inspection offacilities, equipment, working
method, or working procedure
Mean concentration of airborne 1)
Take necessary measures
toxic substances in a unit work areaforworkingenvironment,
exceeds the administrative control
based on the result oflevel
inspectionoffacilities,
equipment, working method, or
working procedure
Control Class Ⅲ
2)
Use effective respirator
3)
Carry
out
medicalexamination or take othernecessary actions to maintainworkers’ health(2) Classification of Control Class
1. Only A-sampling
EA1＜E
Control Class Ⅰ

EA1≧E≧EA2
Control Class Ⅱ

EA2＜E
Control Class Ⅲ

2.Both A and B-sampling
EA1＜E
EA1≧E≧EA2
EA2＜E
CB＜E
Control Class Ⅰ
Control Class Ⅱ
Control Class Ⅲ
E1≧CB1≧1.5×E
Control Class Ⅱ
Control Class Ⅱ
Control Class Ⅲ
CB＞1.5×E
Control Class Ⅲ
Control Class Ⅲ
Control Class Ⅲ
E ：Administrative control level
EA1：1st Evaluation Value
EA2：2nd Evaluation Value
CB ：B-sampling ValueThe Ordinance on the Prevention of Organic Solvent Poisoning stipulates that workplaces whereorganic solvents are handled must install local exhaust ventilation systems. The Ordinance further
stipulates that the capture velocity of these ventilators must be set at a specific level. However, a23

workplace can obtain an exemption from this latter requirement and set the capture velocity on its
local exhaust ventilation systems at a level below that specified by the Ordinance, provided that: (1)the results of work environment measurements show that the workplace has successfully
maintained the concentration of toxic substances at a level corresponding to Control Classification 1
for at least one year and six months; (2) the workplace in question has been grouped in Control
Classification 1 at least three consecutive times; (3) the workplace in question has received
authorization from the director of the competent Labour Standards Inspection Office to lower thecapture velocity setting on its local exhaust ventilation systems; and (4) it is deemed that theworkplace in question will still be able to maintain a concentration level corresponding to Control
Classification 1 even after it lowers the capture velocity setting on its local exhaust ventilation
systems.
8

Implementation of the unified accuracy control project by the Ministry of Labour, JapanThe Ministry of Labour, Japan, entrusts Japan Association for Working Environment Measurementwith the unified accuracy project (including cross check of the result of the working environment
measurement etc.) in order to improve the design, sampling, assay (including analysis) andevaluation in working environment measurement agencies as well as to promote the appropriate
evaluation of the result of work environment measurement and the implementation of the following
countermeasure by employers etc.
9. Work environment control at small and medium-sized workplaces
Small and medium-sized workplaces are also required by law to carry out the work environment
measurements described above, and to take such actions as are shown necessary by thesemeasurements to insure proper work environment control. Japan’s small and medium-sizedworkplaces, however, have not always necessarily had the personnel, technical expertise, or
financial resources required for prompt compliance with this requirement. Nevertheless, small andmedium-sized workplaces are showing an increasing understanding of how important it is that theytake appropriate steps to safeguard the health of their employees before health problems occur. This
fortunate trend has come about thanks to: (1) measures taken by the Ministry of Health, Labour andWelfare to support the efforts of small and medium-sized workplaces (and the businessorganizations to which they belong) in this regard; (2) monitoring and guidance provided by various
government agencies in charge of labour standards administration; and (3) guidance provided bywork environment control experts
10 .The progress achieved in recent years in the area of work environment control
As Fig.7 to Fig.13 shows, the distribution of Control Classes of each work places regarding each
substance continues to be improved, for example, with respect to Average, in fiscal year 2002, as
Fig.13 shows, 89.7 % of all workplaces were placed in Control Classification 1,. The proportion of
workplaces in Control Classification 2 is 6.3 % and the proportion of workplaces in Control
Classification 3 is 4.0 %, respectively.

24

Fig. 7 Dust
120

Control class Ⅲ
Control class Ⅱ
Control class Ⅰ
9.6

4.9
7.8

5.1
8.6

4.6
7.9

4.4
7.8

4.2
7.5

4.5
7.8

85.3

87.3

86.3

87.5

87.8

88.2

87.7

6.5

6.5

6.1

5.1

10.9

10.9

10.6

82.6

82.6

83.2

80

60

40

20

fiscal year
25

20
03
(n
=5
3,
99
0）
20
04
(n
;n
ot
re
le
as
ed
)

13
9）
(n
=5
3,
20
02

(n
=5
5,
40
4)
20
01

(n
=5
3,
07
3)
20
00

(n
=3
0,
59
0)
19
99

(n
=4
6,
93
7)
19
98

(n
=3
1,
46
3)
19
97

(n
=2
2,
69
1)
19
96

(n
=3
0,
23
4)

0

19
95

ratio of control classes

100

Fig. 8 Asbestos
Control class Ⅲ
Control class Ⅱ
Control class Ⅰ

101

100

0.1

1.2
99

0.5
1.1

1.2

2.1

0.6

1

0.6

0.5

1.3

1.4

0.3

0.8

0.9

0.9

2.2

98
2.6
97

1.6
98.7

96

98.0

98.2

98.0

99.1

98.7
98.1
97.2

95

96.3

96.2

fiscal year
26

ed
;n
o

tr

ele
as

50
）
20
04
(n

20
03
(n
=1
,1

1,2
12
）
(n
＝

20
02

20
01

(n
=1
,4
51
)

(n
=1
,54
5)
20
00

(n
=1
,10
2)
19
99

(n
=1
,91
9)
19
98

(n
=1
,38
4)
19
97

(n
=5
00
)
19
96

(n
=1
,41
6)

94

19
95

retio of control class (%)

0.6

Fig. 9 Organic solvents
Control class Ⅲ
Control class Ⅱ
Control class Ⅰ

105

4.2

4.2

3.8

4.0

4.5

3.7

8.2

8.4

2.9

2.8

6.4

6.1

5.7

90.5

91.0

91.5

4.7

7.3

7.4

8.0

8.6

2.5

3.1

95

90

85
87.6

87.4

89.0

88.9

88.0

86.8

92.8

fiscal year
27

re
lea
s

se
d

63
）
20
04
(n

;n

ot

=1
03
,2

20
03
(n

(n
=9
8,
14
6)
20
02

20
01

(n
=1
01
,6
01
)

08
)
(n
=9
6,0
20
00

(n
=5
8,
54
2)
19
99

(n
=8
4,9
14
)
19
98

01
)
(n
=5
4,7
19
97

(n
=3
8,7
80
)
19
96

(n
=5
6,0
98
)

80

19
95

ratio of control class (%)

100

Fig. 10 Specified chemical substances othre than asbestos and metals, from fiscal 1995 to
2003

1.4
2.5

1.6
2.8

2.1
2.9

1.8
3.0

1.9
2.8

2.4
3.0

2.0
2.9

8.0
5.3

5.5
4.3

86.7

90.2

Control class Ⅲ
Control class Ⅱ
Control class Ⅰ

80%

60%
96.0

95.6

94.9

95.2

95.3

94.6

95.1

40%

20%

28

20
03
(n
=2
8,8
50
）

(n
=2
5,
02
7）

5)

20
02

(n
=1
5,
70

8)

fiscal year

20
01

(n
=1
3,
35
20
00

(n
=7
,4
99
)
19
99

2)
(n
=1
1,8
4
19
98

(n
=8
,1
77
)
19
97

(n
=5
,4
98
)
19
96

(n
=7
,1
06
)

0%

19
95

rario of control class(%)

100%

Fig. 11 Metals in Specified chemical substances in fiscal year 2004
Control class Ⅰ

Control class Ⅱ

Control class Ⅲ

Control class Ⅲ, 3.8
Control class Ⅱ, 3.2

Control class Ⅰ, 93

29

Fig. 12 Lead
Control class Ⅲ
Control class Ⅱ
Control class Ⅰ

120

7.5

7.8
6.6

6.0
6.3

4.8
6.7

5.4
6.2

5.5
5.0

5.0
5.5

5
5.1

4.7
4.8

85.1

85.5

87.7

88.4

88.4

89.5

89.5

89.9

90.5

8.3

7.4

8.8

82.9

80

60

40

20

20

d)

04
(

n;

no
tr
e le
as
e

2）
,78
(n
=3
20
03

20
02

(n
=

3,7

62
）

,2
38
)
20
01

(n
=4

,76
7)
20
00

(n
=3

,35
8)
19
99

(n
=2

,52
4)
19
98

(n
=3

,28
6)
(n
=2
19
97

(n
=1
19
96

(n
=2

,41
2)

,78
2)

0

19
95

rtio of control class100

fiscal year30Fig. 13 Average
105.0

Control class Ⅲ
Control class Ⅱ
Control class Ⅰ

4.6

4.7

4.1

4.7

3.9

3.4

3.9

3.1

3.6

4.0

95.0

8.4

8.3

6.9

7.8

8.4

6.3

7.1

5.2

5.8

6.3

90.0

85.0
87.0

87.0

89.2

88.2

86.9

90.2

89.0

91.7

90.6

89.7

31

d)
re
l

19
9,0

(n
;n
ot

(n
=

04

20
03
20

fiscal year

ea
se

56
）

7)
=1
88
(n

20
02

(n
20
01

(n
20
00

,89

,65
=1
86

,34
=1
75

=1
04
(n
19
99

(n
19
98

9)

4)
,98

6)
=1
55

,27
=1
03
(n
19
97

(n
=
19
96

,93

6)

)
72
,9
98

9)
,6
7
=1
02
(n

9)

80.0

19
95

ratio of control class

100.0

11.

Control of work methods

In addition to the installation or upgrading of various equipment (use of air-tight machinery,
installation of local exhaust ventilation systems [including push-pull type exhaust ventilationequipment], etc.) on the basis of an evaluation of the result of work environment measurements,
workplaces are also required to take immediately a number of other measures when they are
deemed necessary. Such measures include: (1) having their employees wear personal protective
equipment; (2) implementing shorter working hours; (3) changing work positions; etc.
12.

Health care

The Industrial Safety and Health Law stipulates that employees whose work involves exposure to
toxic substances must, in principle, be provided with a special medical examination once every six
months. The results of work environment measurements are very helpful to industrial physicians
when they carry out these special medical examinations.
A number of different indices are used to facilitate the effort to discover adverse health effects of
toxic substances at the earliest possible moment. For this reason, employers are required by law toinclude biological monitoring concerning with certain special medical examination programs.
Blood and/or urine tests can be used to check for the presence of various metabolites found in the
blood and /or urine in the special medical examinations concerning with such organic solvents as
xylene, N, N-dimethyl formamide, styrene, tetrachloroethylene, 1, 1, 1-trichloroethane, toluene andnormal hexane as well as lead. The results of these tests provide very valuable information thathelps determine the effectiveness of work environment control.
13.

Occupational health education

In accordance with the requirements of the Industrial Safety and Health Law, employees whose
work involves exposure to toxic substances must receive training regarding: (1) proper work
methods; (2) the health impact of the toxic substances that they produce or handle; (3) the proper
operation of local exhaust ventilation systems, push-pull ventilation equipment, etc.; (4) the properuse of personal protective equipment; etc. This training is indispensable if work environment
control is to be carried out properly.
14. Occupational Safety and Health Management System
The release by the ISO of the ISO9000 series quality control standards and the ISO14000 series
environmental management standards has sparked an international trend toward standardization ofoccupational safety and health management systems. BS8800 has now been released, and the ILO
finalized and issued “Guidelines on occupational safety and health management systems ILO―
OSH2001” in June 2001.

32

Table 4

Guideline on Occupational Safety and Health Management System
Notification No. 53, 1999, Ministry of Labour
Latest amendment on10th March, 2006
Contents
1 Purpose
2 Definition
3 Scope
4 Publication of Safety and Health Policies
5 Reflection of Workers’ opinions
6 Establishment of the Organization of Occupational Safety and Health Management System
7 Documentation
8 Record
9 Study of Hazards and Decision of matters to be implemented
10 Formulation of a Safety and Health Plan
11 Implementation and Operation of Safety and Health Plans
12 Response to Emergency Situations
13 Routine Inspections, Improvement, etc.
14 Studies of Causes of Occupational Accidents and Diseases
15 System Audit
16 Revision to OSHMS
Japan’s Ministry of Labour (Ministry of Health, Labour and Welfare of Today) issued its
Occupational Safety and Health Management System recommendations on 30, April, 1999, and thisguideline was amended in 2006. Its contents are shown in Table 4. The Ministry took this action in
response to the growing recognition of two looming problems in the field of occupational safety andhealth, namely: (1) occupational diseases in Japan are no longer being reduced as quickly as they
once had been; and (2) long-time veterans in the field of occupational safety and health have begun
to retire, yet not enough has been done to ensure the smooth transfer of their know-how to a newgeneration. The Ministry has determined that there is a need to improve the level of safety andhealth in the workplace by: (1) ensuring the safety of workers; (2) improving the health of workers;and (3) promoting the creation of comfortable work environments. To this end, the Ministry hasprescribed a series of PDCA (plan, do, check, and act) activities, and it provides administrative
guidance to encourage workplaces to adopt systems that will enable them to carry out ongoing andcontinuous safety and health management. The basic content of the occupational safety and healthmanagement systems (OSHMS) advocated by the Ministry of Labour is summarized in Table 4.
15 The Amendment of the Occupational Safety and Health Law, especially with respect to the
Systematic Risk Assessment of chemical substances
The Ministry of Health, Labour and Welfare, in order to respond properly to the situation
mentioned-above, amended the Occupational Safety and Health Law, and enacted Article 28-2 asfollows and enforced it, since April, 2006.
(Investigation, etc. to be carried out by Employer)
Article 28-2 The employer shall, as provided for by the Ordinance of the Ministry of
Health,33

Labour and Welfare, endeavour to investigate the danger or harm, etc., due tobuildings, facilities, raw materials, gases, vapours, dust, etc., and those arising fromwork ions and other duties, and based on the results thereof, shall endeavour to takenecessary measures to prevent danger or health impairment to workers, in addition to
taking the measures provided for by the relevant orders of the Ministry of Health,Labour and Welfare.
However, the said investigation except for the one with respect to chemical
substances, preparations containing chemical substances and other substances which
may result in danger or health impairment to workers shall cover the employers onlyin the manufacturing industry and such other industries as provided for by theOrdinance of the Ministry of Health, Labour and Welfare.
2. The Minister for Health, Labour and Welfare shall make publish the necessary
guidelines relating to the measures in the preceding paragraph to achieve appropriate
and effective implementation thereof, in addition to those provided for in paragraphs
1 and 3 of the preceding Article.
3. The Minister of Health, Labour and Welfare may provide individual employers andorganizations of employers with necessary guidance and assistance, etc., in
accordance with the guidelines provided for in the preceding paragraph.
According to Article 28-2, Minister of Health, Labour and Welfare enacted and enforced sinceApril 2006, Guidelines for Risk Assessment on Chemicals, Notification No. 2, Guidelines for Risk
Assessment, March 30, 2006. This Ｇｕｉｄｅｌｉｎｅ covers risk assessment and risk management withrespect to not only harmful chemical substances but also dangerous chemical substances.
The Contents of the said Guideline are shown as Appendix.

34

These OSHMS recommendations highlight the identification of hazards and toxicants as aneffective way to carry out work environment measurements.
15.

Outstanding issues related to work environment control

Four main issues related to work environment control must be addressed in order to achieve further
improvement in the prevention of occupational diseases. These issues are as follows.
(1) Only a little progress is being made in the fight against pneumoconiosis in Japan. We must
step up our efforts in this area.
Japan’s Ministry of Labour (the Ministry of Health, Labour and Welfare of Today) is currently
carrying out the Campaign to Promote Implementation of Comprehensive Measures for thePrevention of Occupational Respiratory Diseases. This campaign is part of the Ministry’s
five-year plan, which runs from 1998 to 2002, and JISHA is lending its complete cooperation
to the campaign.
(2) In addition, we must also make a concerted effort to prevent health problems stemming fromexposure to chemical substances. We continue to see over 300 cases of this type occurring
every year. When the Industrial Safety and Health Law was amended in May 1999, changes
were made to strengthen measures to prevent workers from suffering adverse health effects
stemming from exposure to toxic substances. Toward this end, the amended law now
stipulates that: (1) companies must provide a material safety data sheet (MSDS) when theysell or deliver chemical substances; and (2) from April 2000, companies have to start
implementing guidelines issued by the Minister of Health, Labour and Welfare concerning theproper control of toxic chemical substances that are not now covered by existing legislation.
(3)

One of the areas addressed by the Ministry of Health, Labour and Welfare’s OSHMS
recommendations is the issue of work environment control measures. The Ministry’s
recommendations call upon the top leadership at companies and workplaces to place top
priority on work environment control measures as an indispensable part of management
strategy, and to pursue the said measures in an organized and ongoing manner. Companies
and workplaces are urged to ensure that this sort of management strategy takes firm root.

(4)

International exchange of technology, ideas and experiences in the field of work environment
control is very important.
It was difficult for Japan to establish a work environment control system to ensure theprevention of occupational diseases in the past, and many more difficulties must be overcomein the future as we work to encourage the adoption of work environment control systems insmall and medium-sized workplaces. We would very much like to hear about the ideas andexperiences of other nations including ASEAN ones, so that we might be able to learn fromyour methods.

35

Appendix
Guidelines for Risk Assessment on Chemicals
Notification No. 2, Guidelines for Risk Assessment,
March 30, 2006
1 Purpose
Pursuant to the provisions of Paragraph 2 of Article 28-2 of the Occupational Safety and Health Law, these
Guidelines shall stipulate the basic concept and actions for assessment of risks associated with chemical
substances, and preparations containing chemical substances or other materials that may cause hazards orhealth impairments to workers, so that measures necessary to prevent workers from being exposed to risks
or hazards are appropriately and effectively implemented in each work places based on the results of suchassessment, and aim to promote voluntary safety and health activities by the employer.
As part of the Guidelines for Risk Assessment (Notification No. 1, Guidelines for Risk Assessment, 2006),
these Guidelines shall stipulate detailed matters related to chemical substances, etc. For the sake of
convenience, these Guidelines also include matters that are stipulated in the general guidelines in an
overlapped manner even if there are no detailed matters that should be specified in these Guidelines.
These Guidelines shall also be designed to address risk assessment and associated measures as stipulated in
the Guidelines on Occupational Safety and Health Management Systems (Ministry of Labour Notification
No. 53, 1999).

2 Scope
These Guidelines shall be applicable to all hazards inherent in work performed by workers that may arise
when producing, handling, storing or transporting chemical substances, containing chemical substances
preparations containing chemical substances or other materials that may cause hazards or healthimpairments to workers (hereinafter referred to as “chemical substances, etc.”).

3 Implementation Items
The employer shall implement the following items as part of the risk assessment as well as control measures
to be taken based on the results of such risk assessment (hereinafter referred to as “risk assessment andcontrol measures”).
（1) The identification of hazards and/or risks caused by chemical substances, etc.
（2) An estimation of the severity and the extent of possibility of occurrence of injuries or diseases that might
be caused by hazards and/or risks from chemical substances, etc., identified in item (1) (hereinafter referred
to as “risks”)（3）Setting priorities to reduce the risks estimated under item (2), and examining measures to reduce risks(hereinafter referred to as “risk reduction measures”)（4) Implementing risk reduction measures in accordance with priorities set under item (3)4 Organizational Structure（1) The employer shall implement risk assessment and control measures under the following organization.
(a) The employer shall have the person who supervises and manages an overall business undertaking (whoassumes the highest position in a work places), such as a general safety and health manager, supervise
and manage the implementation of risk assessment and control measures, etc.
(b) The employer shall have a safety supervisor, a health supervisor, etc., in a work places manage theimplementation of risk assessment and control measures.
(c) The employer shall designate a person to take charge of the management of chemical substances, etc.
(hereinafter referred to as a “chemical substance management officer”) from among those who have theability to appropriately manage chemical substances, etc., and have such chemical substance management
officer perform technical work related to risk assessment and control measures, under the management of
the safety supervisor, health supervisor, etc.
(d) The employer shall have workers participate in related activities through opportunities such as a safety
and health committee, a safety committee or a health committee.
(e) In implementing risk assessment and control measures, the employer shall strive to have not only achemical substance management officer but also other competent persons who have professional
knowledge regarding chemical substances, etc., and machinery or facilities associated with chemical
substances, etc., participate in such activities. As necessary, the employer shall seek participation in risk
assessment by persons who are well versed in the characteristics of chemical facilities, experts such as a36

production engineer, and those who have expertise in chemical substances, etc.
（2) The employer shall provide education and training programs necessary to implement risk assessment andcontrol measures to persons designated in item (1) above.

5 Implementation Timing（1) The employer shall implement risk assessment and control measures when work specified in “a”
through “e” below is conducted.
(a) When a structure associated with chemical substances, etc., is installed, relocated, modified or
dismantled(b) When a facility associated with chemical substances, etc., is newly introduced or a change is made to afacility(c) When raw materials that are chemical substances, etc., are newly adopted or changed(d) When a working method or working procedures associated with chemical substances, etc., are newly
adopted or changed(e) Otherwise, when risks perceived in a work places change or are likely to change, such as in thefollowing cases:① If an industrial accident caused by chemical substances, etc., occurred and problems were found in thecontents of risk assessment and control measures conducted in the past
② When new expertise concerning risks or hazards from chemical substances, etc., is acquired③ Because of the elapse of a certain period after the most recent investigation, etc., when the quality ofmachinery, equipments, etc., associated with chemical substances, etc., have been deteriorated due toaging, when workers do not have adequate knowledge and/or experience relative to safety and healthdue to turnover or when new safety and health expertise is acquired（2) The employer shall recognize that it is necessary to implement risk reduction measures before the start ofwork specified in “a” through “d” of item (1) above.
（3） It is also desirable for the employer to conduct risk assessment and control measures when plans
relative to “a” through “d” of item (1) above are formulated.

6 Determination of target with respect to Risk Assessment and Control Measures
Based on the following considerations, the employer shall determine what work is subject to risk assessment
and control measures.
（1) All risks or hazards caused by chemical substances, etc., in a work places shall be subject to risk
assessment and control measures.
(2) Such works as caused, in the past, occupational accidents due to chemical substances, or incidents etc.,
as likely cause risk and/or health hazard due to chemical substances, shall be subject to risk assessment
and control measures.

7 Collection of Information(1) When implementing risk assessment and control measures, the employer shall gather the materials listed
below and make the best use of the information contained in such materials. In gathering the materials, theactual situation of work sites shall be taken into consideration, and not only materials concerning routine
work but also those related to non-routine work shall be gathered.
a. Material safety data sheets (MSDS) for chemical substances, specifications, chemical substances
concerned, information concerning hazards caused by machinery, equipment, etc., associated withchemical substances, etc., andb. Work standards, operation procedures, etc., associated with chemical substances, etc.
c. Information on the surrounding work environment such as the layout of machinery and equipment, etc.,
associated with chemical substances, etc.
d. The results of working environment measurements, etc.
e. Information on situations where multiple employers conduct work in one place, such as hazards caused bychemical substances, etc., arising from several kinds of operations performed in a single locationf. Actual cases of occurrences of accidents and statistics on accidents, etc.
g.. Other materials and information relevant to implementing risk assessment and control measures(2). When gathering information, the employer shall take note of the following matters.
a. When the employer plans to acquire new chemical substances, etc., the employer shall obtain material
safety data sheets (MSDS) for the relevant chemical substances, etc., from those who transfer or provide
said chemical substances, etc.
b. When the employer plans to introduce new machinery, equipment, etc. associated with chemical
substances, etc., from external, the employer shall require the manufacturer of such machinery,equipment, etc., to conduct risk assessment and control measures at the design and production stages of37

said facility and shall obtain the results of such risk assessment and control measures.
c. When the employer plans to use or remodel machinery, equipment, etc., associated with chemical
substances, etc., which is not owned by the said employer, the said employer shall obtain the results ofrisk assessment and control measures conducted by the person or company that owns management title
over such facilities.
d. When multiple employers conduct work in one location, each employer shall obtain the results of risk
assessment and control measures conducted by the master employer to prevent an industrial accident
caused by chemical substances, etc., due to the performance of different types of works at one location.
e. When multiple employers conduct works in one location where risks or hazards from chemical
substances, etc., exist such as where workers may be exposed to chemical substances, etc., each employer
shall obtain the results of risk assessment and control measures conducted by the master employer
regarding such relevant location.

8 Identification of Hazards(1) Based on work standards, etc., the employer shall examine work in detail on units necessary to identify
risks or hazards from chemical substances, etc., and shall identify hazards inherent in each work unit inaccordance with the classification of hazards that is specified in the “Globally Harmonized System ofClassification and Labelling of Chemicals (GHS)” published by the United Nations (hereinafter referred
to as “GHS”), etc.
However, in chemical plants, etc., the employer may divide such a plant into several sections by using amethod of division by a process, a method of division by layout, or other appropriate methods. Then,facilities in each section shall be made subject to risk assessment and control measures to identify hazards
caused by chemical substances, etc.
(2) In identifying risks or hazards caused by chemical substances, etc., as specified in item (1), the employer
shall take into consideration the additional effect of worker fatigue, etc., on risks or hazards.

9 Estimation of Risks(1) In order to determine priorities to reduce risks, the employer shall estimate risks using a method such as
those described below, taking into consideration the severity and the extent of possibility of the occurrenceof injuries or diseases that may be caused by hazards from chemical substances, etc.
a. A method in which the severity of injuries or diseases and the extent of possibility of the occurrence of
injuries or diseases are measured and plotted on vertical and horizontal axes, and risks are estimated byusing a table in which risks are predetermined according to the severity and the degree of possibility
b. A method in which the extent of possibility of the occurrence of injuries or diseases and the severity ofsuch injuries or diseases are numerically expressed based on prescribed criteria, and such numerals areadded or multiplied to estimate the degree of riskc. A method in which risks are estimated by separating the severity of injuries or diseases and the extent ofpossibility of the occurrence of injuries or diseases on a phased basis(2) Notwithstanding the provisions in item (1), the employer may estimate risks with respect to diseases
caused by chemical substances, etc., by using one of the following methods and by taking into
consideration the degree of hazards of and the amount of exposure to the relevant chemical substances,
etc. However, of the following two methods, the employer is encouraged to adopt the method indicated in“a.”a. A method in which a worker’s exposure concentration of the chemical substance, etc., that is subject toinvestigation is measured and the measurement result is compared to exposure limits of the relevant
chemical substance (“occupational exposure limits” published by the Japan Society for Occupational
Health). If the measured exposure concentration is below such exposure limits, the relevant risks may betreated as being within the permissible range
b. A method in which the degree of hazards of the chemical substance, etc., which is subject to investigationand the level of a worker’s exposure to the relevant chemical substance, etc., are measured and plotted onvertical and horizontal axes, and risks are estimated by using a table in which risks are predeterminedaccording to the degree of hazards and the level of exposure(3) In estimating the extent of possibility of the occurrence of injuries or diseases as specified in item (1) and
exposure concentration as specified in item (2), the employer shall be aware of and make use of thefollowing matters.
However, information indicated in “ i ” below shall be required only when such information isavailable.
a. Properties of the relevant chemical substance, etc.
b. Production or handling volume of the relevant chemical substance, etc.
c. Details of work related to the production, etc., of the relevant chemical substance, etc.
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d. Working conditions for the production, etc., of the relevant chemical substance, etc., and the status of
associated facilities
e. Personnel assignments to work related to the production, etc., of the relevant chemical substance, etc.
f. Working hours

g. Installation of ventilation systems
h. Utilization of personal protective equipment
i. With respect to the relevant chemical substance, etc., measurement results of concentration in theexisting working environment or exposure concentration, or results of biological monitoring（4）The employer shall estimate risks relative to chemical substances, etc., as specified in items (1) and (2)in accordance with the classification of risks or hazards specified in the GHS. During this estimation
process, the employer shall consider the following matters.
a. Reliability of functions or measures to prevent industrial accidents (hereinafter referred to as “safety
and health functions, etc.”) such as the installation of safety devices, “off limits” measures and theinstallation of exhaust ventilation systems as well as the ability to maintain such functions or measuresb. Possibility of undoing or ignoring safety and health functions, etc.
c. Possibility of foreseeable intentional or accidental incorrect use or dangerous behaviour, such asdeviation from work procedures or errors in handling
d. Even if the existence of a hazard is not proven, if there are reasonable grounds for suspecting a hazard,
the employer shall strive to estimate risks by assuming the existence of a hazard based on such grounds(5) In estimating risks as specified in item (1), the employer shall take note of the following matters.
a. Accurately identifying those persons who may suffer estimated injuries or diseases and the details ofsuch injuries or diseases
b. Estimating the severity of the most serious injuries or diseases by assuming the worst possible case,rather than by using the severity of injuries or diseases that actually occurred in the pastc. Because it is desirable to use common criteria to measure the severity of injuries or diseases regardlessof their type, the employer shall principally use the number of days absent, etc., due to such injuries or
diseases as the measurement criteria.

10 Study and Implementation of Risk Reduction Measures(1) The employer shall ensure that the measures required by applicable laws and ordinances are fully
implemented. In addition, the employer shall study and implement measures for reducing risks in the orderof priority given below.
a. Cessation of the use of high-hazard chemical substances, etc., or replacement with lower-hazard materials
b. Reduction of the extent of the possibility of the occurrence of injuries or the level of exposure such as bychanging the operating conditions of chemical reaction processes and the form of chemical substances,
etc., handled in a work placesc. Engineering measures such as the adoption of explosion-protected structures for machinery andequipment associated with chemical substances, etc., and double safety devices, and/or industrial hygiene
engineering measures such as the enclosure of machinery and equipment associated with chemical
substances, etc., and the installation of local exhaust systems, etc.
d. Administrative measures such as the preparation of instruction manuals
e. Use of personal protective equipment（2）In studying measures as specified in item (1), the risk reduction measures to which a higher priority isgiven must be implemented in as much as possible, except for cases in which the burden incurred to reducesuch a risk is substantially greater than the expected effect of preventing an industrial accident, leading to asignificant imbalance between the cost and effect, and where the implementation of such measures is
considered highly irrational.
(3) If a long time is required to implement appropriate risk reduction measures for risks that might lead tofatalities, residual disability or severe diseases, provisional measures shall immediately be taken.

11 Recording
The employer shall maintain a written record of the following activities.
（1）Investigated chemical substances, etc.
（2）Examined and identified work or process（3）Identified hazards（4）Estimated risks（5）Priorities established for risk reduction measures(6) Details of implemented risk reduction measures39