44 C120-H007-05EN
CHAPTER 4 Air Conditioning
4.3.6 Seawater (salt damage)The air in the vicinity of coastal areas contains large amounts of airborne sea salt
particles. If these particles remain inside computers, substances are formed by a
condensation reaction of chemicals. These substances and the humidity lead to
insulation failure and the corrosion and deterioration of components and materials.
Therefore, computers should be installed in locations at a distance from coastal areas.
The following outlines installation criteria for preventing salt water damage due to
airborne sea salt particles.
Criteria: The installation site shall not be within 0.5 km of the ocean or coastal areas
(unless the computer room uses air conditioners to filter out airborne sea salt particles
from outside air).
Nitrogen dioxide (nitrogen oxide) (NO2) Up to 52 ppb
Ammonia (NH3) Up to 420 ppb
Ozone (O3) Up to 5 ppb
Oil vapor Up to 0.2 mg/m3
Table 4.4 Tolerable limits for corrosive gases (2/2)
Gas name Tol era bl e li mit