Solutions Visits the Magic Kingdom

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1 $9.00 December 2006 Vol. 43 No. 12 The Official Publication of ASCR International Solutions Visits the Magic Kingdom Disney Inside: Visit Florida Fire Chemistry 101 Effective Containment Creating Dynamic Presentations

2 FIRE Chemistry 101: Fire Losses & Electronics Restoration By Lawrie Hollingsworth, E.E. 2 Cleaning & Restoration December

3 From homeowners fires to commercial and industrial fire losses, the need for restoring affected electronics is an important part of fire loss mitigation and there are many issues surrounding the recovery of electronics. As restoration professionals, we know that a variety of materials burn in a fire. For example, plastic, wood, insulation and metal all generate smoke particulates that create different types of contamination and damage. This contamination impacts not only electronic equipment, but also the viability of electronics restoration after fire losses. From corrosives to thermal impact, various factors must be considered. Electronics are sensitive to a wide range of contaminants present at fires: Water Smoke and soot Ambient moisture Chemicals Dust and debris Internal dust Aside from heat, the most damaging part of a fire that affects electronics is the chemistry of the fire itself smoke, soot and what s in it. Fire Chemistry Of all the common materials that burn in a fire, plastic has the potential to do the most damage to electronics. Most common household and office plastics are made from polyvinylchlorides (PVCs). These items range from children s toys, wall and floor coverings to PCs and printer cases, phones and more. When these burn, the PVC is broken down to release hydrochloric acid. The smoke now contains the released acid, which gets deposited everywhere as a part of the smoke, commonly forming chlorides on many surfaces. These chlorides are corrosive by themselves, and when combined with the moisture from fire fighting and combustion, they often re-form hydrochloric acid, or HCl on metal surfaces. It is this continuous cycle of chlorides to acid and acid to chlorides that are most detrimental to electronics. On occasion, sulfides and sulfates and other salts are generated as well, with their resulting corrosive properties. The level of contamination, potency of the corrosive elements, and water/moisture plotted against time become the enemy to electronics. Chlorides are most pervasive, but how do you determine if chlorides are present? A generally accepted procedure is to take wipe samples that are then sent out to a laboratory for measurement of chlorides. This involves wiping sterile gauze saturated with deionized water or isopropyl alcohol across a surface showing (or suspected of) signs of smoke contamination. The measurement is usually in micrograms/inch square (µg/in 2 ), and readings of chlorides typically range from zero to 50 µg/in 2. Table 1 summarizes the implication of the findings from various research articles: 1,2,3 Table µg/in2 Normal background concentration µg/in2 Readily recoverable µg/in2 More damage possible, recovery should begin immediately >600 µg/in2 Metals and electronics are in danger if neutralizing and cleaning is not performed immediately, and may not be fully recoverable Our firm utilizes our own proprietary semi-quantitative spot test that develops on-site in about 60 seconds. We have found in the course of our many restoration projects that Table 1 is fairly indicative of what to expect. One factor, the presence of moisture/high humidity, greatly impacts the timing of recovery. If chemical sampling is unavailable, the presence of orange colored rust on steel, blue-green corrosion on copper and wet or salty galvanized metals (e.g., electrical conduit or airconditioning ductwork) after just a few hours is a strong indicator of this type of corrosive contamination. Rule of thumb: The more moisture present, the faster corrosion can occur, and the less time for restoration to be viable. What Makes Equipment Vulnerable to Various Contaminants? Now that we are familiar with one of the most corrosive of contaminants, let s examine why electronic equipment is especially vulnerable to this contamination. Cooling fans and air vents draw daily operational dust into PCs, televisions, stereos, phone systems, copiers, plasma TVs, etc. Dust collects moisture, smoke and other contamination in concentration on circuits and connectors. Without this fine powdery dust, the electronics would not retain moisture or collect it from ambient humidity as readily or in such concentration. December 2006 Cleaning & Restoration 3

4 The Dust Story: Why are electronics vulnerable to moisture & high humidity? Public Enemy #1 Most electronic equipment has cooling fans and/or cooling vents. These provide a stream of air to cool electronic components against the severe build-up of heat generated by the electrical operation. Over time, these fans draw dust into the interior of the electronics. This fine dust may be heavy or lightly deposited throughout the printed circuit cards, components and assemblies. After a disaster such as fire or flood, water and moisture may come into direct contact with computers, phone systems, medical electronics, etc. Additionally, the relative humidity may be high due to water released from fire fighting, burst pipes or weather elements from an open roof. The dust immediately absorbs this moisture even if the equipment is not directly impacted by the water. Without this dust, the moisture would not adhere as readily to the surfaces of the electronics. This moisture begins to corrode the electronic components on the printed circuit cards causing short circuiting and damage. Additionally, if powered on, galvanic or electrolytic corrosion ensues. This occurs when electricity flows through the corrosion. It may be because the device is powered on, or if the equipment has a battery such as a PC does for time and date, the battery will supply electricity. This corrosion resembles the corrosion on the terminals of a car battery. Left unmitigated, the circuit cards will begin to corrode and may produce intermittent failures. These failures can be very hard to diagnose and may result in lost data, computer failure and network problems. In equipment such as a phone system, the result may be static sound and noise when listening to a call, lost voic and so forth. Other types of electronics such as CNC control systems in machinery, medical electronics and office equipment are equally as vulnerable to this type of damage. Mitigation Recognizing that high humidity may be as damaging as direct water contact, the first step is to begin immediate dehumidification of the premises. Next, if practical, remove the equipment to a dry location until relative humidity is established and maintained at no more than 45 percent RH until premises mitigation is completed. Equipment should be opened and inspected, and recovery procedures performed. These should include: 1) Thorough removal of all dust through disassembly and cleaning. 2) Complete removal of any rust or corrosion. 3) Drying the subassemblies in environmental ovens for 1-2 hours at 50 C. 4) Reassembly and evaluation of any units to determine the need for repairs. Courtesy of ART: Asset Recovery Technologies, Inc. The moist dust combines with the corrosives in the soot/ smoke, helping to hold the corrosives on the metal surfaces of circuit boards and supplying the needed environment to ignite the corrosion process. Even in cases where smoke/soot contaminants themselves are not corrosive, they will still have a detrimental effect on electronics. For example, a heavy layer of soot deposited on the internal circuitry of TVs can cause thermal damage to a television from heat buildup if the set continues to be used. Assessing the Damage Before attempting recovery, first determine if the equipment is economically viable to restore. For example, a vintage VCR player that can be replaced new for $60-80 scarcely justifies restoration. On the other hand, especially with home theater electronics or in commercial losses, the equipment may have a much higher dollar value. In the case of computers, it may be necessary to take whatever steps are necessary just to preserve the data, even if the hardware will eventually be thrown away. 4 Cleaning & Restoration December

5 Keep in mind that for commercial losses, the cost of business interruption must factor into the restoration equation. Consider that while equipment may ultimately be replaced, if it can be returned to temporary operation through restoration, it may be justified on the basis of conserving business interruption costs. Next, observe the equipment carefully. Are there signs of thermal damage such as melted wires, connectors or a misshapen case? If so, restoration is probably not a good idea. Observe rusting/corroded hardware such as screws, backsides of computers, connectors and brackets. Note the color: Are they rusty? Are connectors green? As discussed, if available, chemical sampling can help assess damage and validate restoration. If chemical sampling is not available, ordinary litmus or ph paper can be used to measure the level of acidity of the corrosion. Any reading of 4 or lower indicates acidity that must be cleaned and neutralized. Bright orange rust is indicative of new rust, likely fire-related, while dark brown colored rust is older. A green color is consistent with the corrosion of copper and indicates possible damage to electronics. The presence of rust is a sign that restoration should begin immediately. With this background on fire-related damage mechanisms in mind, here are the first steps to preserve electronics until restoration can take place. Triage: Emergency Steps to Preserve Electronics If powered off, do NOT let the property owner turn on affected equipment. If powered on, advise that equipment be shut down as soon as possible, backing up data if necessary. Note: In addition to hazards from moisture and contaminants, power surges from burnt/damaged electrical wiring and from the interaction of power and the smoke contamination itself can destroy not only a single computer but also any equipment attached to it. Gain control of the environment (dehumidify to as low a relative humidity as possible, wipe soot from electronics, cover holes in the roof whatever steps are necessary). If possible, remove affected equipment from the site to a humidity-controlled environment. From plasma screen TVs to computer networks, the pervasiveness of electronics makes their mitigation an ever increasing part of the restoration equation. Lawrie N. Hollingsworth, E.E., is a certified disaster recovery planner and president of Asset Recovery Technologies, Inc. To learn more about the company, visit References 1 Reagor, B.T. Smoke Corrosivity: Generation, Impact, Detection and Protection, Journal of Fire Sciences, Vol. 10, March/April, Sinclair, J.D.; Psota-Kelty, L.A. and C.J. Weschler. Indoor/Outdoor Concentrations and Indoor Surface Accumulations of Ionic Substances. Journal of Atmospheric Environment, Vol. 19, No. 2, pp , Krzyzanowski, M.E. Applications of Ion Chromatography in the Disaster Recovery of Electronic Equipment, 41st Annual Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy, N.Y., NY, March, FIRE Chemistry 101 Reprinted with permission from the December 2006 issue of Cleaning & Restoration magazine, 2006, Association of Specialists in Cleaning & Restoration. December 2006 Cleaning & Restoration 5