Particle Counts can affect the hardware performance in computer datacom environments. The negative influences range from intermittent interference to actual component failures. So Particle Counts should be an integral part of the facility maintenance protocol. Because particle counts measure particulate suspended in the air, they do not address settled particulate. In fact, it’s possible for a facility to be well within the threshold criteria on a particle count basis and still have significant visible contamination. At the very least, such visible contamination is an aesthetic concern. More likely though, the settled particulate may be disturbed and become a significant airborne threat. Therefore, Particle Counts are necessary but not sufficient to evaluate and monitor the cleanliness of the facility.

Historically datacom environments used Federal Standard 209E - Class 100,000 as the threshold criteria for cleanliness. This standard has been sunsetted. The replacement standard is ISO 14644-1. The equivalent threshold under the ISO standard is Class 8. The rough threshold is 100,000 0.5 micron particles per cubic foot of atmosphere.

Again, it is entirely possible (and likely) that the particle count results for a well maintained datacom environment will be well below the 100,000 threshold level. In this case, the Class 8 threshold value becomes irrelevant. Instead of ignoring the particle count result, the user is encouraged to establish a relevant facility-specific particle count baseline. Then subsequent measurements can be evaluated against the baseline with a high degree of relevance.

A robust particle count based cleaning protocol will utilize airborne contaminate particle counts as part of inspection and  monitoring program and establish trigger events based on changes in the particle counts. For example, if a particle count increases more than 20% since the last count, accelerate the next cleaning service to the first available date within the next 30 days. If a particle count increases 40%, the next cleaning service should be scheduled within a week. In either case, an investigation into the cause of the change should be undertaken. The cause of any significant particle count decrease should also be investigated and understood.

Particle counts should not be conducted within 72 hours of a cleaning event to allow disturbed particulate to settle.