By Rebecca Averbeck
A burglar left his "ID card" at the scene of the crime. You can't see it, but it's there. He entered the house through a window. Pieces of glass lay on the ground, wet from the recent rain. Inside the house, there's a screwdriver with black plastic tape wrapped around the handle that might have been used to pry open a desk drawer.
You've shined your flashlight at a low angle to see if there are any visible fingerprints; you've dusted; you've even used magnetic powder. Nothing. At this point, some investigators may be frustrated and give up.
John Olenik, an Ohio fingerprint examiner for 27 years, says don't give up. A fingerprint process known as cyanoacrylate, or "super glue," fuming may save the day - or at least the fingerprint that identifies the burglar. Many state and metropolitan law enforcement agencies use this process. But, Olenik emphasizes, fuming must be done correctly. In many cases it's not being done right, and many latent prints are over-looked or lost. Olenik saw this happening when he worked with hundreds of agencies through his job at the Ohio Bureau of Criminal Identification & Investigation lab. A certified instructor through the Ohio Peace Officer Training Academy, he has focused on teaching super glue fuming workshops since retiring as an examiner in 1996. Through his workshops, Olenik aims to clear up false ideas about fuming and encourage agencies not using the process to give it a try. Going back to the scene of the burglary, latent fingerprints probably could have been recovered from the broken window glass and the plastic tape wrapped around the screwdriver.
Super glue fuming is a process in which these types of items are placed into an airtight chamber and exposed to super glue vapors. A chamber could be a fish tank, a plastic bag held up by PVC pipe or a commercial chamber. The super glue used in fuming is an adhesive with basically the same active ingredients as artificial nail adhesives or popular glues with trade names Super Glue or Krazy Glue. When vaporized, the glue reacts to traces of moisture and organic components of fingerprint residue. As a result, fingerprint residue often turns white and becomes polymerized - or bonded - to the surface. Super glue-bonded prints generally last for years.
With proper super glue fuming, investigators should be able to double the number of usable fingerprints they get in comparison to the number they got without fuming or with improper fuming, Olenik says. The U.S. Army Criminal Investigation Laboratory- Europe has documented this. From June 1988 to February 1989, its latent print division kept statistics on cases received at the laboratory that were determined to be appropriate for cyanoacrylate fuming. David Perkins and William Thomas wrote an editorial about this study in the Journal of Forensic Identification, Vol.41, No.3, 1991. The data showed about 3.29 latent prints were developed per case for those cases fumed in the field compared to 1.06 for those that were not fumed.
Fingerprints are very fragile, because high temperature and low humidity can dry out fingerprint residue and make recovery impossible. Unlike a fingerprint brush that can wipe away a print, super glue fuming is a technique that generally won't alter or destroy prints. Fuming also can preserve fingerprints on some surfaces, like vinyl, that otherwise would absorb fingerprint residue in a matter of hours or days.
After fuming, additional print enhancing with powders or dyes can be done a day, a week or a month later. Olenik developed a fluorescent magnetic fingerprint powder, solvent systems for fluorescent dye staining on cyanoacrylate-developed prints, as well as photographic techniques for the capture of fluorescent prints. He has presented his findings at international fingerprint and forensic symposiums and sells some of his products through his business, Detecto Print.
1. Chemical acceleration-Frank Kendall, a fingerprint examiner from the Bureau of Alcohol, Tobacco and Firearms, discovered that putting superglue on absorbent cotton treated with sodium hydroxide, caustic soda or lye would cause an exothermic reaction. So much heat is generated from this reaction that the fuming process is complete in less than five minutes. "Most of the super glue, I found out, is used to generate the heat, and only a small quantity comes off as a vapor," Olenik says. "It was the first rapid technique, but it still was, I feel, a little on the crude side because you could not accurately control the amount of super glue fumes. And, some difficult surfaces respond better to slow fuming techniques." Chemical acceleration often is used for field applications on containers that may have contained drugs, tools found at a crime scene, and beverage containers, such as bottles or cans. Both do-it-yourself and commercial chemical acceleration products are available.
2. Heat generation-When Olenik was working on his bachelor's degree at the University of Akron in Ohio, he thought there might be another way of heating the glue. By talking to polymer chemists at the university and looking up patent literature on how Super Glue is made, he found that polymerization retardants could be added to the glue so most of it would go into vapor form when it was heated. "If you take a drop of super glue and put it on a glass slide and heat up the slide, almost all the vapors or all the glue will cure out on itself in one solid blob. Hardly any vapor will come off," says Olenik, who published the first article on using polymerization retardants and heat sources. "But, if you use aluminum foil as a reservoir for super glue, the foil acts as a polymerization retardant You can heat the glue and almost all of it will come off as vapor." Safe heat sources that can be placed into a chamber to accelerate fuming include a 60-watt light bulb or a coffee cup warmer. Heat sources to avoid because they generate too much heat include soldering irons and hot plates. "I feel heat generation techniques are the most efficient techniques to use," Olenik says. "They work on any surface that is receptive to super glue fuming and work especially well on difficult surfaces like black electrical tape, wooden gun stocks and rubber gun grips."
3. Increasing the surface area-Like water, super glue is volatile to a certain point. Spreading super glue as a thin film on an aluminum foil pouch increases the glue's surface area. "It's just like taking a cup of warm water," Olenik said. "You can let the warm water in the cup stay there and it might take days for it to evaporate. But if you take that same cup of warm water and pour it on a tabletop, it's going to evaporate a lot more rapidly. All you've done is spread it out as a thin film, so you've got more of the surface exposed to the air, and more of it can volatize off." There are commercial aluminum foil pouches and "home made" pouches. Commercial pouches have, in addition to a polymerization retardant, a gelling or thickening substance so the glue doesn't run. As soon as this pouch is opened, fumes are emitted. Olenik published an article to help law enforcement officers save money by making their own pouches. Super glue fuming by increasing the surface area lends itself to fuming large areas such as the inside of a car or even an entire room.
4. Vacuum chamber - Developed in Canada, the vacuum chamber technique involves removing all of the air from the chamber with a vacuum pump. This reduces the atmospheric pressure and allows the glue to volatilize off in a short amount of time and has the unique ability to penetrate into small crevices. Using a vacuum chamber is perhaps the best technique for many surfaces. If a plastic bag is fumed in a vacuum chamber, fingerprints may develop even on the inside of the bag. This technique works the best on recently deposited prints. On dried-out prints, the evidence may need to be re-humidified. Disadvantages to this method include: the size of the item that can fit in the chamber is limited and it can be costly. Olenik received an award from the governor of Ohio for saving Ohio thousands of dollars by building efficient, inexpensive vacuum chambers for fingerprint development at the Ohio bureau's three crime labs.
Super glue fuming is done about every other day or every third day in Aurora. Firearms, ammunition and car parts are the most common items fumed. "I 'super glue' everything I can. Super glue fuming enables us to do multiple processing steps," Dabney says, noting evidence is photographed after each process. "We 'super glue' before we do anything else."
The Springfield Police Department started using a vacuum chamber last fall. Before Springfield had a vacuum chamber, a coffee cup warmer was used inside a vented custom-made cabinet chamber with a glass front. Fuming is done in the lab about three times a week. Guns are fumed to fix prints and plastic bags with drugs are fumed to reveal fingerprints inside as well as outside the bag. "Anything metallic we're probably going to fume, if it fits inside," added Sgt. Greg Fels, a 19-year Springfield veteran. Usually, evidence is small enough to fit inside of the cabinet chamber or the vacuum chamber. Something the size of a woodchipper or larger would not fit, Fels says. Another chamber could be constructed for something this size, but the nature of the crime also plays a part in whether or not fuming will be done. "If a woodchipper was in a theft, we're not going to fume it. We'll use black powder, but if it was somehow used in a homicide, we'd build a tent out of plastic bags and fume it that way," he says.
For fuming at the scene of a crime, investigators keep super glue fuming supplies in tackle boxes in their vehicles. Packets of sawdust and baking soda are ready to use as accelerants inside chambers made with plastic bags. This is one of the inexpensive accelerants they learned about at Olenik's workshop.
Springfield has sponsored cyanoacrylate-fuming workshops and has tried to spread the word about the importance of super glue fuming to smaller law enforcement agencies. Small agencies that mail evidence to state labs for processing may lose evidence if they don't use super glue fuming, Fels emphasized.
Fuming is not expensive - it can be done with a bottle of glue, a catalyst to heat it and a chamber for less than $30, Dabney says. "I call fuming an insurance policy," Sullivan says. "It's not a catch-all or cure-all, but fuming will buy you a second lift or processing technique. Super glue fuming is like dipping an ice cream cone in chocolate--the process puts a hard coating, or shell, over moisture and oils. The outer shell over the top insures recovery of a print."
Super glue fuming dont'sNo matter what cyanoacrylate, or super glue, fuming technique you are using, John Olenik of Detecto Print says, there are several things to keep in mind so that the process is done correctly.
August 1998. Law Enforcement Technology 57
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