Zinc Whisker Remediation
What Causes Zinc Whiskers?
Metal surfaces are coated with zinc in a galvanization process to help protect them from corrosion. Particleboard core floor tiles made from the 1950’s until the early 1980’s were formed by applying a zinc-electroplated passivation coating to the sheet metal pan on the bottom and sides of the tile. During the plating process internal stresses occur to the metal that later leads to zinc whiskers, or needles, forming on the surface.
What Are Zinc Whiskers and Where Can They Be Found?
Zinc whiskers, or needles, occur as filaments extending from the treated surface. The whiskers are 2 microns in diameter and become a problem when they reach a length of 500 microns, after approximately two years. They can grow to a length of over 2,000 microns if undisturbed for a long period of time (many years). Under proper lighting, they can be visible to the naked eye on surfaces and inside equipment.
What Are the Dangers of Zinc Whiskers?
When the floor tiles are disturbed, or over time, the whiskers break off, become airborne, and are ingested into the computer equipment. Since they are so small, filtration is not effective in stopping zinc whiskers. Zinc whiskers are conductive and can cause shorts on cards, power supplies, or other electronic components. Zinc whiskers can also cause voltage variances without damaging the component. Zinc whisker growth has been found on sub-racks, switches, card cages, floor tiles and other electroplated surfaces.
What Options Do You Have?
There are three options in how to deal with zinc whiskers. The decision on which option to select should be determined by the potential life of the current data processing facility:
If the life of the current facility is not expected to exceed 5 years before moving or major renovations, then a cost savings can be experienced through short term care. Regular cleaning of the sub-floor and tiles (every 6 months). The room(s) will be sectioned off by building a mini “clean area” by making a barrier of plastic from the ceiling to the sub-floor. This way, contamination from the work area does not spread. The entire sub-floor, including the sides and bottoms of the floor tiles, will be vacuumed using ULPA-filtered vacuums. The bottoms and sides of the floor tiles, as well as the grid and pedestal system, will be wiped with a MATRIX SYSTEM Tec Mitt that has been treated with Formula Science Corporation’s MATRIX SYSTEM ENVIROSOLVE Formula to remove the zinc needle growth. The mitt will be rinsed and changed frequently to prevent redistribution of contaminants and debris. During the first clean all exposed concrete and other porous surfaces should be prepared for coating with ENVIROSEAL. The cleaning process will be repeated throughout the room.
If the life of the current facility is going to be between 5 and 10 years before moving or major renovation, then a more comprehensive solution is suggest. Work area will be isolated and tiles will be removed and encased while inside “clean area”. Tiles will then be taken to a “clean area” and go through the complete MATRIX SYSTEM recoating process designed by Formula Science. The “work area” will be completely cleaned (sub-floor and grid and pedestal system as described in the short term care solution. The sub-floor will be sealed with Enviroseal. The COMPLEXä Polymeric Barrier provides a non-reactive layer of protection from the corrosion catalysts of moisture and oxygen. However, if the film integrity of the coating is violated through mishandling, ZN can begin to form just as they originally developed on the zinc-electroplated coating that resides beneath. For this reason, it is very important that facility personnel are competent in the proper handling of tiles and proper care of the facility after the tiles have been reinstalled.The MATRIX SYSTEM process utilizes new AFT Fluoro-Tech Polymer Technology to provide treated tile surfaces with indefinitely lasting protection against Zinc Whisker development. With proper handling to prevent damage to the coating, treated tiles can be utilized for decades without concern or negative consequences.
If the life of the facility is going to be beyond 10 years, or for the only 100% guarantee against future Zinc Whisker growth, complete tile replacement is the most popular option. The computer room must still be isolated and cleaned properly, as well as the sub-floor sealed. Tiles must be bagged before removal from the “work area”. The area must be cleaned and sealed and new tiles installed prior to moving to a new “work area”.