It is the top of this page

About photochemical smog

 In this page, characteristic and Kanagawa of photochemical smog to be generated in summer speak measures to want you to take "photochemical smog alarm" that Kanagawa announces because "photochemical smog information" to announce prevents health hazard every day when others, health hazard about information about photochemical smog alarm for PC and cell-phones occur every year.

Last update date March 27, 2020

 Representative air pollution matter until the 1960s was sulphur dioxide (SO2) which sulfur included in fuel (heavy oil or coal) used in factories burnt, and there was, but air pollution material which entered in the 1970s, and attracted attention at a bound was photochemical oxidant (OX) which caused problem and photochemical smog that it was in Los Angeles City.
 There was case that received unidentified health hazard while a large number of high school girls exercised at ground in Suginami-ku, Tokyo on July 18, 1970 (Showa 45) with opportunity when photochemical smog came to attract attention of in Japan and was that it was revealed that it was caused by photochemical smog by investigation of Tokyo pollution research institute. With this case, each local government arranged the monitoring system of photochemical smog using tele meter system to prevent health hazard.

With photochemical smog

 Nitrogen oxide (NOx) and volatile organic compounds (VOC) drained from factory and business ground or car in the atmosphere catch ultraviolet ray included in sunbeam and wake up chemical reaction (photochemical reaction) and change in quality, and "photochemical oxidant" and oxidizing materials such as ozone (O3), aldehyde, peroxyl acetyl nitrate (PAN) named generally are generated secondarily.
 We stay in the summer when sunlight is strong, and temperature is high, and climatic condition such as wind being weak is piled up without these materials generated by photochemical reaction being scattered in the atmosphere (without fading away). As a result, the sky is veiled and may be in a condition that white haze appeared and far-off mountain or building are veiled and may become hard to be seen. It is said that "photochemical smog" produces this state.
 When photochemical oxidant becomes highly-concentrated, we stimulate mucous membranes such as eyes or respiratory organs, and health hazard may occur.
 It is said that the first health hazard caused by photochemical smog in Kanagawa occurred in Kawasaki-shi on August 15, 1970 (Showa 45) one month later after the first health hazard is confirmed in Tokyo.
 In Yokohama-shi, we had report of health hazard more than 6,000 in 1975 (Showa 50). In addition, most of victims who had report so far were primary schoolchild and junior high students such as after school program outdoors.
 In addition, there may be influence such as leaf of plant dying.

Characteristic of photochemical smog

 Such as next which is different from other air pollution phenomena in photochemical smog is characteristic.

  1. As a result of nitrogen oxide and hydrocarbon exhausted in the atmosphere bathing in solar strong ultraviolet ray, and having changed in quality to highly-concentrated photochemical oxidant, photochemical smog occurs, and it features that wind occurs at the summer daytime when ultraviolet ray is strong weakly. Therefore, it does not occur in winter when ultraviolet ray is weak or the night when the sun does not appear. On the other hand, density rises in winter when the atmosphere "is stable" as for other air pollution materials, and nitrogen dioxides (NO2) are easy to become in a state (climatic condition that pollutant is hard to scatter in the atmosphere) from November through January.
  2. As air containing pollutant moves with wind, there is not particularly big outbreak source, and photochemical oxidant may become highly-concentrated in area where density of other pollutants including nitrogen dioxide is low.

Photochemical smog alarm

 Kanagawa announces forecast and warning about photochemical smog to prevent health hazard caused by photochemical smog.

It is this about official announcement standards such as photochemical smog alarms that Kanagawa announces.
It is this about emergency measures such as photochemical smog alarms that Kanagawa enforces.
It is this about aging changes such as the official announcement number of times of photochemical smog alarm announced in Yokohama-shi.
Table 1 photochemical smog readout (with Kanagawa air pollution emergency measures summary)
Division of informationContentsEmergency measures
NoneThere is no news about photochemical smog now.There are no emergency measures
Type BBy climatic condition, today (tomorrow) is ○○ area ※In this of photochemical smog might occur.There are no emergency measures
Type A (forecast)Today (tomorrow) is ○○ area ※Fear that photochemical smog is generated in this is big.There are emergency measures

Present, ○○ area ※Photochemical smog alarm is announced by this.
In area during warning official announcement, we restrain ourselves from use, going out of car and radical exercise of schoolchild, student.

There are emergency measures
Warning, serious emergency warning

Present, ○○ area ※Photochemical smog warning (serious emergency warning) is announced by this.
In area that we alarm (serious emergency warning) and are announcing, we stop radical exercise of use of car, self-restraint of going out and schoolchild, student.

There are emergency measures

"○○ area" is official announcement local division such as photochemical smog alarms.

Offer of photochemical smog information

 By telephone service, the Internet (PC version, cell-phone version), E-mail delivery, we give information about having outbreak or not of photochemical smog to prevent health hazard caused by photochemical smog in Kanagawa.

1. Telephone service

Phone number of telephone service (Kanagawa) is 050-5306-2687.

 In Kanagawa, we provide information whether or not photochemical smog is generated in the prefecture by telephone service in days from April through October.

 As a general rule, contents change at 10:00 (forecast on that day) and 17:00 (the next day forecast). In addition, the latest information is provided one by one until warning is lifted when warning was announced.

2. Reporting by the Internet

 We tell about information such as official announcement area or the official announcement time, the cancellation time when (contents of table 1 mentioned above) or photochemical smog alarm were announced whether photochemical smog is generated in Kanagawa in Web site.

Air pollution result of a measurement home (Kanagawa) to continuously monitor is this. (the outside site)

3. Reporting with E-mail

 When photochemical smog alarms are announced in Kanagawa, we carry out service to deliver information (official announcement area, the official announcement time, photochemical oxidant density at the time of official announcement) about official announcement, cancellation such as warning by E-mail.

Registration method of mailing list (Kanagawa) of air pollution information is this. (the outside site)

 In Yokohama-shi, we added "photochemical smog information" to "disaster prevention information E-mail" which we delivered for cell-phone and home PCs. When photochemical smog alarms are announced, E-mail is delivered to Yokohama-shi

Registration method of disaster prevention information E-mail (Yokohama-shi) is this. (the outside site)

Prevention of health hazard

 We distribute the following flyer to schools in the prefecture, and Kanagawa calls for attention to protect children from damage of photochemical smog.

Flyer is Web site of Kanagawa "to protect children from photochemical smog" and can see. (the outside site)
  1. Symptom of health hazard is ...
    (1) Symptom (we have a pain in eyes that eyes sting cry) of eyes
    (2) Symptom (a cough having a pain in throat comes out choking) of respiratory organs
    (3) Other symptoms (nausea, headache)
    Of slight illness comparative in most of these symptoms is transient, and, in the scene of damage, the outdoors are often found.
    It is many cases, exercising damage the outdoors to report severe symptom, but there are people whom symptom does not appear even if there is in the same situation, and there are individual differences.
  2. When photochemical smog was generated; ...
    The feature is that children have many healthy victims of photochemical smog. Please carry out next to prevent health hazard of children.
    (1) Sickly child and child who on the day is ill-conditioned let me take a rest indoors.
    (2) Please avoid radical exercise if possible.
    (3) Please close window if possible.
  3. When health hazard occurred; ...
    When health hazard occurs, you note the next matter, and please take appropriate measures immediately.
    (1) You cancel all the exercise the outdoors and evacuate indoors and wash your eyes with water, and please gargle.
    In addition, please close window indoors if possible.
    (2) When symptoms such as numbness, dyspnea, faint of hands and feet occur, please receive treatment for doctor.
    (3) When you feel abnormality as it is said that children such as ophthalmopathy, respiratory illness, hyperthyroidism, allergic predisposition are easy to receive health hazard in particular, please receive treatment for doctor.
    (4) As it is thought about damaged child coming under a psychological influence about damage, please consider not to give unrest.
  4. Report of health hazard
    When health hazard occurs, please let know to Health and Welfare Center Health Sanitation Division of environmental monitoring center or each ward office about the next matter.
    (1) Time for damage occurrence
    (2) Address of damage occurrence or Name of the facility (e.g. :○○○ park)
    (3) Full name, age, school year, sex, contact information, the number of damaged people
    (4) The situation of damage and symptom (stimulation, dizziness, numbness, dyspnea such as eyes, throat)
    (5) The situation of measures

Inquiry to this page

Environmental Planning Bureau environment Maintenance Division Environment Administration Division

Telephone: 045-671-3507

Telephone: 045-671-3507

Fax: 045-641-3580

E-Mail address [email protected]

Return to the previous page

Page ID: 737-619-506

We come back to the top