The following article from Law Enforcement Technology magazine.

'Super Glue to the Rescue'

Scarcely visible fingerprint evidence can be saved with proper fuming.

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.

How fuming works

Both the glass and plastic are non-porous and suitable for super glue fuming. Anything a drop of water would roll off of would be good evidence to fume, says Olenik, who started teaching six years ago. In addition to glass and plastic, other examples of surfaces suitable for fuming include the cover of this magazine, metal and rubber.

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.

Why glue really is super

Faint prints, which could not be seen with the naked eye or with the help of powders, can become visible after fuming. And prints that could not be seen immediately after super glue fuming can become visible with dye staining and specialized lighting techniques.

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.

Ways to accelerate fuming

Since super glue fuming was first documented more than 20 years ago in Japan, numerous techniques and variations of techniques have been developed to accelerate the process. Some people refer to the first super glue fuming process as the "slow fuming process." Super glue was poured into a small dish, which was placed into a chamber along with items to be fumed. A lid was placed over the chamber, and it was checked every couple hours to see if prints became visible. "The technique was very crude from the standpoint you didn't know how much glue to use, and you didn't know when you would get results. It could be 12 hours or 24 hours," says Olenik, a member of the International Association for Identification and chairman of the innovative and general techniques subcommittee. Olenik, who has developed two super glue fuming techniques, divides accelerated fuming processes into four categories:

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.

Don't get stuck - or worse

When Olenik conducts his workshops, he emphasizes safety. Olenik conducts six-hour workshops for law enforcement agencies, including federal agencies, throughout the United States. He has taught more than 30 this year. Cyanoacrylates can cause extreme eye and nose irritation. Fuming should be done in well-ventilated areas. Try to avoid breathing super glue fumes. "There have been instances of people becoming sensitized to super glue fumes, and this is not too well known in this country," says Olenik, who is helping spread the word. "People can abuse super glue fuming for months or even years and have no ill effects whatsoever. Then, all of a sudden, they develop an allergic reaction to it." Symptoms can include a severe headache, skin rash or difficulty breathing. Once you become sensitized, you should avoid exposure to fumes completely. "There are some techniques, like when you 'super glue' the inside of a car, where I recommend wearing a full protective mask," he adds. Cyanoacrylates can bond skin. "You can glue your fingers together quite easily," says Olenik, who talks about first aid in his workshops. Wearing disposable rubber glues can help keep skin from bonding. It's a good idea to have some type of glue solvent in case an accidental spill occurs. Do not wear cotton gloves, even if they are more comfortable. Glue goes through cotton gloves and bonds skin. Cyanoacrylates reacting with cotton generate heat and can cause burning. When heated beyond decomposition temperature, cyanoacrylates can emit hazardous products. The decomposition temperature of cyanoacrylates is about 300 or 400 degrees C.

Give super glue fuming a try

Members of the Springfield Police Department in Missouri and the Aurora Police Department in Illinois attended Olenik's class. Both departments have been super glue fuming for about 10 years and recently started using vacuum chambers. They found this technique produces clearer fingerprint ridges. Aurora started using a vacuum chamber a couple months ago. Prior to the vacuum chamber, Sgt. R.P. Sullivan says, he used the "poor man's way of fuming," heating the glue with a light bulb or coffee cup warmer inside a 10-gallon fish tank with a Plexiglas cover. "In a fish tank, you can't control the humidity and get even coating along the surfaces," says Sullivan, who's been with the department for 13 years. "In a vacuum chamber, you can vacuum out the moisture and control the application of fumes and get an even coating." Officer Michael Dabney, who's been an Aurora officer for almost 16 years, says, "If the humidity is higher than 70 percent, instead of trying to lower the humidity, we place it in a vacuum. With the wrong humidity in a fish tank, you can end up obliterating the evidence in seconds or minutes."

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's

No 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.
  • Don't forget temperature and humidity play key roles in fuming. The ideal temperature for fuming is about toom temperature, 70 to 80 degrees F. The ideal humidity for fuming is 80 percent.
  • Don't fume in a chamber with a lot of super glue residue in it. Super glue will react with itself. If your chamber is not clean, most of the vapors will go towards the sides of your chamber instead of toward the evidence. "keeping a clean chamber is something that most police departments ignore," Olenik says, but you shouldn't have to clean the chamber after every run. How often the chamber needs cleaning depends on the type of the chamber. A plastic bag can be used two or three times before it should be thrown away. A fish tank can be used three or four times before it needs cleaning.
  • Don't over fume. One of the biggest misconceptions is that you have to wee dence, white ridges before the print is properly developed. In most cases, if a print has dense, white ridges, it's over fumed. Over fuming can damage prints or make thme harder to see.
  • Don't forget super glue does not always fix every print due to the nature of the surface. If a surface has been contaminated with furniture wax or a silicon spray, for example, a print may vanish when you go to powder it or process it further. When you see a good print and the surface may be contaminated, photograph it to preserve the print. Every surface doesn't react the same with super glue fuming.
  • Don't use fingerprint tape on evidence that's been fumed and not powdered. "Sometimes when officers see a good print, they'll super glue it and they'll cover the print with fingerprint tape to preserve it," Olenik says, "but they're not preserving it, they're destroying it." Fingerprint tape will actually absorb the super glue residue after a few weeks or months. When something is super glued, it's already bonded to the surface. It does not need any specialized handling. However, it could be transported or stored in a plastic or paper bag or a cardboard box.
  • Don't store the glue in high temperatures. "I've had departments store a bottle of super glue on a metal shelf and expose the glue to sunlight from the outside. The super glue would start curing out on itself and turn into a thick syrupy mass," Olenik says. "Then in a matter of months or so, it would turn into a solid, white piece of plastic." Super glue should be kept out of bright sunlight and stored in a refrigerator.

August 1998. Law Enforcement Technology 57

More info...Increasing the Surface Area.

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