IT Cleaning Ltd, were asked to sample some black dust from a clients data centre, and get it analysed. This dust had been found when removing equipment, however, it was not visible it had marked someone’s white shirt. To help with the sampling we put a new white bag in our Nilfisk HEPA filtered back pack vacuum. We then vacuumed 3 cabinets, and all the equipment. The results can be seen. ” Bearing in mind the dust could not be see on the equipment, or cabinet doors, the transformation and amount we collected is amazing” .. “This is another example of hidden contamination within Data Centre’s, we await the lab results, on what this dust is”. Stephen Yates Director.
UPDATE Results from the Lab:
Conclusion: The sample of dust contained 48.7% Carbon, 6.42% Hydrogen and 6.33% Nitrogen. This is a high carbon content, and I draw my conclusion below on this. The remainder of the substances were metals from 30,000 mg/kg of Iron Oxide to 3.5 mg/kg of Arsenic and 13,000 mg/kg of Zinc. All of these metals including the Strontium (fluorescent paint) are common in data centres.
a. Carbon. I asked our client to supply me with information about the ACU drive belts currently used in the Data Hall. The data sheet provided showed the belts to be made of CR (polychloroprene), which is neoprene. Further investigation found the following: Neoprene is an acyclic monoolefins these have the general formula CnH2n, C being a carbon atom, H a hydrogen atom, and n, an integer. It is my determination that the black dust collected in the sample was mostly Carbon and therefore, I hypothesis that this is drive belt residue. I have used logic to deduce this as follows. Having looked further into synthetic rubbers, neoprene being one example, they all contain a lot of carbon, and I for one do not know where other forms of carbon within the data hall dust sample could have come from. Especially as almost 50% of the dust was carbon.
Recommendations: The problem with belt residue is universal in data centres with belt driven downflow units see https://www.itcleaning.co.uk/data-centre-cleaning-danger-within for another example of this in a data centre we clean. There are a number of options:
a. Change to direct drive down flow units. This is expensive and difficult to install in a working data centre.
b. Increase cleaning, this is often a cost-effective method. The use of 0.3µm air-scrubbers will filter the air during the cleaning removing any dust made airborne during the cleaning.
c. Once cleaning completed, introduce filters on the A.C.U. outlet or the cabinets inlet side. Both b and c, must be done carefully as the reduction in airflow may have a detrimental effect on the cooling of the equipment.