There are two types of airborne contaminants that most data centers have to contend with: solid particles and gases. Even with a physical separation of equipment in a data center, industrial processes can produce unacceptable levels of particulate contamination in the form of airborne dust and gases, which can damage sensitive electrical components, and lead to costly repairs and replacements.
To determine is there any risk of airborne contamination of any sort at your facility. Begin with a visual inspection. Look for rusting and corrosion on exposed metal, noticeable odors of airborne chemicals such as chlorine, ozone or sulfur, depending on possible by products of your industrial processes, and layers of dust on equipment.
Particulate contaminants can impact the sustained operations of computer hardware. Effects can range from intermittent interference to actual component failures. Therefore airborne contaminants should be maintained within defined limits to help minimize their potential impact on the hardware by regularly scheduled data center cleaning.
ISO 14644-1 cleanroom classification
ISO 14644 cleanroom classification is now the accepted worldwide standard for classifying the cleanliness of the air in cleanrooms and clean zones.
ISO 14644 states contamination levels as the maximum number of particles per cubic meter of air in six distinct sizes. Permitted concentration of particles for each considered particle size is determined from threshold sizes defined by the standard. Air cleanliness class by particle concentration is designated by an ISO Class number.
Recommended Air Particulate Concentration Levels
Cleanrooms operate at different classes of cleanliness depending on what their purpose is. The lower the ISO Class, the fewer particles in the room and, consequently, the cleaner the room is. Most cleanrooms like those used in medical device manufacturing or the aerospace industry are ISO Class 5 to 8.
ASHRAE recommends that data centers should be kept clean to ISO Class 8.
