Contamination does not originate within the data center itself but enters through multiple, often overlooked, pathways in the facility's infrastructure and daily operational activities. Identifying and sealing these entry points is fundamental to any effective control strategy, as each represents a breach in the data center's environmental defenses.The primary entry points for data center contaminants include:
HVAC Systems: As the main gateway for outside air, HVAC systems are the most significant source of airborne pollution. In urban or industrial areas, vehicle emissions and manufacturing byproducts are drawn directly into the facility. Standard HVAC filters, such as MERV 8, are often inadequate and allow fine, damaging particles to pass through into the data hall.
Unsealed Penetrations: Gaps and openings in the building envelope act as direct conduits for contamination. This includes unsealed cable penetrations through walls and floors, gaps around door and window frames, and even small, unused drill holes. These pathways allow dust, moisture, and polluted air to bypass filtration systems entirely.
Raised Floors: The subfloor plenum is a critical area for contamination. Unsealed concrete subfloors continuously shed fine dust and mineral particles directly into the cold air supply stream. This environment is a primary source of zinc whiskers, the microscopic conductive filaments that can cause immediate and catastrophic short circuits described later.
Personnel and Maintenance Activity: Human activity is a major contributor. People shed skin cells, hair, and clothing fibers. More significantly, their movement agitates settled dust, making it airborne again. Maintenance and construction activities are especially high-risk, introducing drywall dust, metal filings, and other debris that can circulate for months.
Moisture Infiltration: Humid air entering through any unsealed penetration can condense on cooler equipment surfaces. This moisture acts as a catalyst, dissolving gaseous pollutants into corrosive solutions and allowing conductive dust particles to create electrical short circuits.Once these contaminants breach the facility's perimeter, they are circulated by the cooling systems, eventually finding their way into the sensitive internal components of IT hardware.