In the previous article we wrote about Laminar Flow Cabinets and their basic definition.
We also introduced our product – HDDS Horizontal Laminar Flow Cabinet M.
The laminar cabinet engine draws air from the environment and directs it to the space where the filter is, which can be HEPA or ULPA. These filters have efficiency for stopping the particles with a diameter greater than 3 microns.
Laminarity, i.e. the rectilinear parallel air flow at all points is provided by the perforated sheet that lies in front of the filter.Parallel air movement ensures that each particle that is eventually found in the work space is ejected outside the chamber.
Working space, i.e. the area in which the analysis is performed or the operation of the object is in a state of elevated pressure (overpressure) and the air is in constant laminar motion, so the retention of particles is impossible.
The air velocity that is optimal for hard drives and which provides laminarity is from 0.3 to 0.5 meters per second.
The platters on which the data is entered are very sensitive to dust and general contact.
Magnetic writing / reading requires a little distance between the head (for writing and reading) and the surface used for the arrangement of magnetic particles. This “little distance” is 60-100 nanometers when the hard drive works.
It should not be forgotten that the platters rotate at a speed of 5400, 7200, and more than 10,000 rpm.
The particle of the diameter of the micron is still very big for the head that floats on a distance of nanometer.
It is true that many particles will be removed from the surface when the disc is rotated, but there are also those which are sticky and magnetic, so there is a danger that they could land on the platter surface.
Therefore, for any intervention where a hard disc drive needs to be opened, it is necessary to minimize the risk of contamination of the platters by using Clean rooms and laminar flow cabinets.
In order to prove this, we’ve examined a hard drive while working in both clean environment and a regular one.
At first, we counted the bad sectors on closed hard drive:
Then, we opened the same hard drive inside the Cabinet:
In the end, we opened that hard drive in our office, where the regular air is:
As expected, the analysis showed rapid increase of bad sectors in the case when the hard was opened outside the clean area.
Full report can be read here.
Since the release (and even before), our HDDS Horizontal Laminar Flow Cabinet M has been a great success and a lot of DR companies wanted to have it in their offices.
As we understand the importance of having a clean cabinet in every lab, we decided to give a special discount for August 2017.
Each customer who contact us from Forensic Focus will receive 20% discount for our Laminar Cabinet.