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WES provides construction and physical remediation services for customer sites. While the Engineering Site Assessments are stand-alone engineering services, they often result in recommendations for further engineering and remediation services. Working as a team with the customer, WES provides a full complement of services to help eliminate existing and potential threats to hardware reliability and uptime.
Site Preparation Services (Return to Top of Page)
New Site Preparation
A Site Preparation Project prepares a customer site for high-end reliability. Site Preparations typically include appropriate decontamination of hardware surfaces, floor surfaces, walls, fixtures, supply air plenum surfaces, air conditioners and other relevant areas. A Site Preparation can also include encapsulation of the subfloor supply air plenum deck and perimeter wall surfaces. Environmental conditions are monitored closely during this project.
Decontamination Services (Return to Top of Page)
Decontamination Project
During the Decontamination Project all data center surfaces, which include hardware, access floor, walls, fixtures, supply air plenum surfaces, air conditioners, and other relevant areas are appropriately decontaminated. The project can be designed to address above floor conditions, subfloor conditions, or both. Once appropriate conditions are achieved, the subject area should be placed on a program of regularly scheduled decontaminations.
Hardware Decontamination Services
The Hardware Decontamination Project is designed to remove loose deposits of building materials or construction dust from within hardware. These deposits may be the result of long-term building material degradation, be associated with specific renovation or construction activities, or be a result of a disaster. Addressing these contaminants can typically be achieved through appropriate implementation of filtered compressed air, brush, and vacuum techniques employed on the disassembled components. Direct exposure to fires, floods or reactive chemical gasses typically requires chemical bath treatments or factory refurbishments.
It is essential that only appropriate products, equipment and procedures are utilized so as to avoid any inappropriate impact on the hardware. All actions must be designed with appropriate consideration to the type of contamination and contaminant levels. This service is typically designed as a joint program with the hardware supplier or maintainer.
Decontamination & Encapsulation Treatment
This service combines the Data Center Decontamination Project with encapsulation of the subfloor supply air surfaces. The encapsulation process utilizes only appropriate sealants, equipment, and procedures so as to ensure that it does not adversely affect the environmental conditions in the subject areas. The encapsulant utilized by WES has a high flexibility and low porosity to ensure efficient coverage. There will be no harmful out-gassing properties from the encapsulate that could have an effect on the on-line facility. The WES encapsulant is pigmented to ensure complete coverage and will be manually applied to avoid atomization in the supply airflow. During the encapsulation treatment process all unsealed supply air plenum surfaces should be addressed. This includes those areas beneath cables or other moveable items.
Zinc Whisker Abatement
For over 50 years, the electronics industry has been aware of the threat posed by Zinc Whisker growth on surfaces with a zinc-electroplated passivation coating. During recent years, growing concern has developed in computer rooms where these conductive contaminants form on the bottoms of some access floor tiles and are distributed to hardware where they cause failures or degraded performance.
What are Zinc Whiskers?
Metal surfaces are coated with Zinc in a galvanization process to help protect them from corrosion. While several techniques are used, such as hot-dip or spraying, whisker growth appears to be limited to electroplated samples. Several industry studies have shown that whisker growth is dependent on internal stresses during the plating process. The whiskers are Zinc (Zn) filaments extending from the treated surface. They are normally only a few microns in width but can be several hundred to over a thousand microns long. Under proper lighting they can be visible to the naked eye on surfaces.
Where are Zinc Whiskers found?
Zinc Whisker growth has been found on sub-racks, switches, card cages, floor tiles, and other electroplated surfaces. The whisker growth can occur on surfaces within the hardware, or can be carried to the hardware from outside sources. Not all electroplated surfaces exhibit whisker growth and not all develop the problem at the same rate. The influencing factors are not fully understood at this point, though environmental factors are suspected.
Whisker growth on access floor tiles is a particular concern. These tiles have large surface areas and are often disturbed during normal activity in the computer room. Since the subfloor void of most computer rooms is used as a duct, the susceptible surfaces of these tiles are within the supply airflow. The Zinc Whiskers can easily be dislodged and carried to the hardware. Floor tiles are often dragged across the top of each other as they are removed from the floor grid, spreading the contamination throughout the room.
How do Zinc Whiskers cause failures?
The Zinc Whiskers are conductive contaminants. They can cause shorts on IC cards, power supplies or other electronic components. Identification of the source of such a failure can be extremely difficult. Often the contaminant will be dislodged during handling and shipping and the component will function normally when tested at the lab. In some cases, the contaminant will not cause a short but will cause voltage variances that can interrupt service without damaging the component. At sites with an identified Zinc Whisker problem, field technicians have had short-term success in reusing parts by blowing compressed air on the surface of a failed circuit board.
Why have I not heard of Zinc Whiskers before?
While the electronics industry has been aware of the threat of these conductive whiskers for many years, older electronic designs were less susceptible. As technology evolved, circuitry became much denser and operated at lower voltages. The growth of Zinc Whiskers is not new but its ability to impact hardware reliability has been increased by the denser geometry of the newer technologies.
What do the hardware manufacturers say about Zinc Whiskers?
Several hardware manufacturers and industry groups have published warnings regarding the potential impact of Zinc Whiskers on the reliability of electronic components. The IBM AS/ 400 Physical Planning Reference V4R1 states that, "Raised floor tiles that have a Zinc-electroplated passivation coating have the potential to grow Zinc Whiskers. IBM believes that Zinc Whiskers cause intermittent AS/400 operational problems." In its NUMA-Q™ Systems Site Planning Guide, Sequent Computer Systems cautions that Zinc Whiskers, "can break off and become airborne particles. If Zinc Whiskers land in power supplies or electronic equipment with dense circuitry the shavings can cause a short that damages the system." In its customer services documentation, Amdahl warns that, "Accumulations of contaminants within the computer room can adversely affect equipment availability," and lists among these, "Zinc extrusions on floor tiles." This problem has also been documented by FUJITSU, Bellcore and numerous industry groups.
What can I do if I suspect a Zinc Whiskers problem?
The presence of Zinc Whiskers can be verified by experts using specialized field and laboratory tests. An inspection of your site can identify the source and degree of any conductive contaminant problems. If Zinc Whisker growth is identified on your floor tiles, extreme caution must be used in addressing it to avoid making matters worse by spreading it throughout the room. The most appropriate action is the replacement of all floor tiles with the selective encapsulation of inaccessible tiles. This is an extremely delicate and labor-intensive procedure involving specialized high efficiency decontamination and encapsulation of appropriate air plenum surfaces to trap residual contaminants. The project must employ appropriate monitoring and must be planned with proper regard to contaminant isolation and conditioned air distribution to minimize the possibility of impacting hardware up-time. Such drastic measures are not always necessary and consultation with experienced specialists is strongly recommended. Worldwide Environmental Services can help determine the solutions that are right for your site.
Contact a WES representative if you have any questions on Zinc Whiskers or if you would like to learn more about our decontamination services.
Hardware Protection Services
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Hardware Environmental Protection Agreement
The Hardware Environmental Protection Agreement (HEPA) is a custom designed maintenance program for the data center. It will typically include regularly scheduled decontaminations of data processing areas such as: hardware, access floor, walls, fixtures, supply air plenum surfaces, air conditioners, and other relevant areas on a semi-annual, quarterly, or monthly schedule. All visits include monitoring of the computer room environment to track conditions.
Subfloor and Ceiling Services (Return to Top of Page)
Access Floor Replacement
Suspended Ceiling Replacement
Subfloor Plenum Divider Construction
Subfloor Cable Removal
Access Floor Replacement
This service is designed to address damaged access floor tiles. It may include cosmetic improvements (replacing gasketing, end-caps or cut-out collars, cleaning tiles), replacement of the access floor tiles within the existing support structure, or may include optimization (leveling, re-adhering floor-jacks, tightening bolted stringers, etc.) or replacement of the entire access floor support structure.
Suspended Ceiling Replacement
In order to address moisture retention and/or contaminant concerns, the suspended ceiling service is designed to replace damaged or inappropriate suspended ceilings in a data center controlled environment. The may include replacement of inappropriate (porous or shedding) ceiling tiles with computer room grade (non-shedding foil or vinyl face) tiles within the existing suspension system, optimization of the suspension system, or replacement or removal of the entire suspended ceiling.
Subfloor Plenum Divider Construction
Integrity of the subfloor perimeter is integral to moisture retention and the maintenance of appropriate supply plenum pressurization for efficient air distribution. This service will assist the client in constructing or maintaining the subfloor air plenum. Minor penetrations will be appropriately filled or sealed. In areas with larger openings or areas lacking subfloor perimeter walls, subfloor plenum dividers will be constructed from non-shedding materials with appropriate fire ratings. Appropriate vapor retardants will be incorporated into the design.
Subfloor Cable Removal
This service can include identification of unused power or data cabling, or may be limited to physical removal of identified cables.
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