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necessity of photocatalyst construction







    VOC (Volatile Organic Compounds), which is fatal to human body, is the general term of organic compounds which causes photochemical oxidation reaction with NOx by sun light in the atmosphere, and increases ozone concentration of the earths surface, and finally makes smog phenomenon, it has hundreds of kinds.

    It is said that VOC is discharged the most within 6 months after new building construction.

    It was reported that in foreign countries, harmful materials are discharged from the adhesives which is in common use to stick tiles or the floor 10 years after the construction.

    When exposed to VOC of high concentration, acute disease such as narcosism (suppression the central nervous system), dizziness, paralysis, and death can occur.

 Pollutants and disease occurred inside the building

Main reason



Smoke gas, adhesives, paint remover


Hemostasis function troubles

construction materials, Refrigerant of refrigeration system(Freon)

Halid hydrocarbon

Liver poisonous, arrhythmia, sudden death, carcinogenic

Artificial fabrics,

Synthetic resin


Loss of eyesight, decline of  pulmonary function, carcinogenic

Lumber, adiabatic materials, carpet,

veneer adhesives


Allergic dermatitis,

Paint, wax for the floor, varnish, dyes, wall paper

Toluene, xylene

Vomiting, illusion, nausea,

Impotent feeling

Material wood, leather couch


Stimulation to eyes,

Decline of reproduction function

Extract of edible oil, adhesive solvent, synthetic leather finishing stuff, precision instrument cleaner

Normal hexane

Peripheral nerve disease


Harmful materials

Purification environment effect


Agent of disease, origin of germs infection, various germs, offensive odor

Antibiotic, deodorization, protection from secondary infection in the hospital


Offensive odor, ammonia, dirt

Deodorization, antipollution


Dirt, harmful materials of tobacco

Antibiotic, deodorization, antipollution

Institution for the aged

Agent of disease, colon bacilli, various germs

Antibiotic ,protection from infection,


Meal service,


Colon bacilli such as O-157, offensive odor, dirt, seasonal bacilli

inhibition various bacilli, deodorization, antibiotic, antipollution

Food depository

Various bacilli

Antibiotic, antipollution


Offensive odor, dirt, various bacilli

Deodorization, antibiotic, antipollution


Offensive odor, dirt, various bacilli

Deodorization, antibiotic, antipollution

Fluorescent lamp


Antipollution, antibiotic

Pet center

pets excretions and odor

Antibiotic, deodorization


Mold, incrustation, grime, drainage way odor

Mold prevention, antibacilli

Outside a building

Auto exhausts

Self cleaning



1. Increase of the time staying indoor (90% of 24 hours)

2. Increase of harmful hormone materials due to industrial pollution

3. Harmful gas warning-VOCs are 3~4 times of European standard

4. Frequent yellow sand due to extraordinary climate (including photochemical smog and ozone creation material)

5. Legal control (pollutant due to industrial development)



■  Control of indoor air in the multipurpose utility facilities
[Ministry of Environment]

(Obligatory from May 30, 2004)


    Multipurpose facilities controlled by the law will be expanded to 17 facilities suchas terminals, parking lots, libraries, hospitals from underground station buildings, andunderground shopping centers.

<Multipurpose facilities>

Facility name


Underground station buildings

Every underground station building

Underground shopping center, passenger terminal, waiting room of the terminal, indoor parking lot

Total area over 2000 m2

Passenger terminal of port facilities

Total area over 1500 m2

Terminal among port facilities

Total area over 5000m2

Library, Museum, art gallery

Total area over 5000m2

Medical institution( more than 100 beds)

Total area over 5000m2

Underground funeral place, national nursery institution, national institution for the aged, pay institution for medical treatment, hospital especially designed for the aged,

Total area over 5000m2

Facilities for fomentation

Total area over 5000m2

Facilities for the convalescence after childbirth

Total area over 5000m2

Huge shops

Every huge shop

  The person who is in charge of maintenance of multipurpose facilities has to be educated in the institute which is arranged by Ministry of Environment within 1 year from Jan 1, 2005.

  The maintenance standard of the indoor air quality concerning fine dust, and formaldehyde has been established, and it should be observed. 


<Indoor air maintenance standard>

pollutant ▷  





Total floating bacilli


   Underground station building,

   Underground shopping center,

   Waiting room of Passenger    terminal, waiting room of train    station, passengers terminal of air    port facilities, waiting room of port    facilities, library, museum, art    gallery, funeral place, facilities for    fomentation, huge shops







   Medical institution, nursery    institution,  medical institution for    the aged, Facilities for the    convalescence after childbirth



   Indoor parking lot




  The person responsible for maintenance of the facilities should measure the pollutants and submit the result to the provincial governor.

  The person who constructs the multipurpose facilities should install the air purifying equipments and ventilation equipments over certain standard.

  It has been decided to report construction materials that release pollutants such as formaldehyde, TVOC over the standard and not to use in the facilities. 


Indoor air quality maintenance of new apartment houses

    After the enforcement of the law, the constructers who build new apartment house of more than 100 families should measure the pollutants before the moving in, and post a notice on the places where can be easily found for 60 days when they apply for the business plan approval or building permit.



Water pollutants

Aromatic organic acid, phenol, alcohol. Surfactant (organic phosphate compounds, nitrogenous compounds), coloration substance (aromatic hydrocarbon), cyanide, heavy metal, crude petroleum, organic chlorine compounds (trichloroethylene, tetrachloroethylene, PCB, etc,)

Air pollutants

organic chlorine compounds, volatile hydrocarbon, aldehyde, alcohol, phenol, ammonia, hydrogen sulfide, nitrogen oxidized substance, sulfur oxidized substance



    Centering on the developed countries centering around Japan, the regulations concerning the environment tends to reinforce. As a result, the regulations concerning the environment pollution will be reinforced, and these regulations will work as an important inducement of the photocatalyst industry activation.


Maintenance standard of indoor environment

Foreign standard


carbon monoxide



150 (Japanese law concerning building hygiene maintenance, Japanese law concerning labor safety and hygiene l)

10(Japanese law concerning building hygiene maintenance , Japanese law concerning labor safety and hygiene)

20 (Japanese school hygiene standard)

9(WHO standard, 8hours)

35( WHO standard, 1hour)

carbon monoxide(ppm)


    1000(standard of construction, building, labor safety hygiene)
1500( school environment
standard, Japan)
920(WHO standard, 8hours)

Temperature/relative humidity,
air current,
Illumination, bacilli,
carbon dioxide (ppm)

Keep 17~18c/ 40~70%
0.5 m/sec
Keep over 100 lux


10~30 (standard of school environment , Japan)
30~80%(standard of school environment , Japan)
over 200 lux(standard of school environment , Japan)
more than 30
0.21( European standard)
5( Industry hygiene allowance, Japan.)

Sulfurous acid gas(ppm)


5( Industry hygiene allowance, Japan)
0.04(일본 공해 대책 기본법)



0.1( European standard)
2( Industry hygiene allowance, Japan



0.01(유럽 석면 긴급 대책법) / 2( Industry hygiene allowance, Japan)



100 (WHO New built residence in Europe)
70 (New built residence in Sweden)
100 (Ministry of Science & technology, Japan)
3700 (Department of mine hygiene, USA)