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WATER DAMAGE - EFFECTS AND PROCEDURES |
WARNING: DO NOT ENERGIZE ANY WET EQUIPMENT - REMOVE POWER
It is a popular misconception that electronic equipment exposed to water is permanently damaged. Water which has sprayed, splashed, or dripped onto electronic equipment can be easily removed. Even equipment which has been totally submerged can be restored. The most important issue in the amount of damage is whether the equipment was powered at the time of exposure
• Open cabinet doors, remove side panels and covers, and pull out chassis drawers to allow water to run out of the equipment.
• Remove standing water with wet vacs Use low pressure air (50 psi) to blow trapped water out of the equipment. Absorbent cotton pads (diapers?) can be used to blot up water. Use appropriate caution around header pins and backplane wire wrap connectors to avoid bending.
• Vacuum and mop up water under any raised computer room floor.
• Equipment which contains open relays and transformers will require a special bake out before application of power.
• Water displacement aerosol lubricant sprays may be used to protect critical components.
Magnetic, Optical, Information Media
The First 24 Hours of exposure to the effects of Water will usually determine if emergency steps need to be taken to clean, restore and preserve magnetic data storage media. This plan is intended only as a guideline for deciding if professional restoration services maybe required due to exposure from the following potential sources of damage:
The media under consideration includes but is not limited to:
DO NOT USE MAGNETIC MEDIA THAT HAS BEEN EXPOSED TO CONTAMINANTS
The most important asset, which must be preserved after a disaster, is the critical data on magnetic media. A professional should examine media that has been exposed to contaminants before any attempt is made to use them. A
95% to 100% restoration success is possible predicated on 72 to 96 hour response time.
Removable Hard Disk Platters
Hard disk data
can be partially saved - even after a head crash. This process is very labor intensive and requires special equipment in a clean room. Contaminated media is replaced with clean media. Restoration of data is a process involving the emergency cleaning of the media so that data may be copied onto other media. The original media will be discarded (or archived).
Disk read/write heads are subject to severe damage if an attempt is made to operate with media which is not clean. A "head crash" caused by particulate on the surface of the hard disk media will not only damage the drive, but may cause loss of data.
Floppy disks with hard particulate matter on the surface could cause damage to the oxide layer and may destroy data as the floppy spins. Water can dissolve the adhesive between the substrate and the magnetic oxide coating resulting in loss of data. If the media is wet, keep it wet until professional restoration.
Tapes must be dry and clean before any attempt is made to copy the data.
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Initial mitigation
includes removing standing water. Open cartridge access door and shake out water. Use clean low pressure air to force water off. Remove rings on reel tape for the same purpose
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Keep the media wet
until restoration can be applied. Use zip-lock bags, plastic trash-can liners, etc.
• Do NOT attempt to dry with heat!!!!
A CD disk contains from 650 mb to over a gigabyte depending upon format. This data layer is read through the optically clear substrate material by a low power laser diode Anything such as a scratch or particulate can interfere and cause a data error. The protective lacquer coating on CD-ROM disks can be very thin. The lacquer coating side of a CD is the side with the printed label, artwork, and/or track information. If this layer is scratched, the data layer is directly exposed to the environment and degrades at an accelerated rate. The surface must be protected until restoration can be used to remove contaminants. If optical media is wet, keep wet until it can be cleaned.
Magneto Optical (CD RW)
is processed the same as other optical media.
Microfilm, Microfiche, X-Ray Film
The most important thing to know about microfilm is that once the film is wet do not let it dry!! The film must be processed while still wet or the gelatin coating will stick to the next layer and the document information will be torn from the film. Here again, speed is of the essence:
• For short time storage, five gallon buckets can be used to store film with enough (preferably distilled) water to cover the film. Zip lock bags or plastic cellophane wrap can also be used to package the film and prevent drying. (keep film cold 35 to 45 degrees)
• Use gloves when handling wet materials and wash hands thoroughly to prevent infection from flood bio-contaminants
• For longer storage than a few days, a conservator must add special gelatin hardening chemicals to water.
• For long term storage, the film may be frozen without damage. Film can never be freeze-dried - it must be thawed and wet processed.
Documents & Vital Records
Preventing Damage to Paper, Books and Microfilm
One of the most daunting tasks faced by record managers is recovering wet documents. Fire suppression, floods, rain, sprinkler pipe breaks and other disasters can leave paper records, microfilm and microfiche soaked with water. While you might think otherwise, 100 percent recovery is possible if you respond quickly. The basic strategy is to keep photographic media from drying and blocking, and to freeze paper documents to prevent further damage (which is the only way to save gloss finished paper). Here are the steps you should follow for recovery:
1. Seal the film.
Photographic media (microfilm, microfiche and x-ray film) should be your first priority. Prepare a list so the contents can be tracked. Then, box and seal to prevent drying, refrigerating (at 35¼ - 40¼ F) if possible
2. Freeze the paper.
Puckering, swelling, ink smearing and blocking occurs as long as paper is wet. Inventory these documents, pack in boxes with plastic liners, palletize, and freeze. Once frozen, the damage ceases and the loss is in stasis until restoration can be accomplished.
For critical documents and special collections, blast freezing is best but seldom available in the time frame required. The freezing process is usually accomplished with refrigerated trucks that will transport the documents to the closest freeze dry facility for restoration (see step five below)
If documents are covered with silt (as a result of flooding), they are rinsed and cleaned on site before freezing. Remember that once frozen, documents become blocks of ice; if the unit you wish to consider is less than a box, separate the documents into modules with plastic or wax paper before freezing.
3. Separate vellum and leather bound documents.
Vellum and leather are derived from animal skin and should be carefully separated from the rest of the documents. Drying should be done slowly and in a controlled fashion. Unlike other materials, they should not be heated during the freeze dry process.
4. Reprocess the microforms.
As implied above, the emulsion layer on film will stick to contiguous substrate if it is allowed to dry, resulting in tearing and loss of data if you subsequently attempt to separate the film. Restoration involves machine reprocessing of wet microfilm and manual processing of fiche and other photographic film. Film may also be frozen for indefinite storage without further damage. For restoration, it must then be thawed and wet processed.
5. Freeze dry frozen paper documents.
The next trick is to dry the paper without exposing the documents to the liquid phase. This can be accomplished by forcing sublimation (solid-state to vapor-state drying) in a freeze dry chamber with sufficient vacuum.
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