At the present time police departments around the country are feeling the budget pinch and looking for ways to do more with less, should that come as any surprise to property officers and evidence technicians?
In a recent Sun Times article it was reported that State Auditor William Holland found a backlog of DNA cases in Illinois had more than tripled between 2002 and 2007 the last year of his study. Further that over 70 percent of police departments contacted said they experienced tardiness issues with the State Police Labs for DNA evidence and other cases submitted to the lab. It has been reported that the number of forensic scientist employed by Illinois State Police has dropped by 3 percent and the state has paid out 16 million dollars to outside vendors to reduce backlogged cases over a seven year period.
In the last two decades, DNA evidence has become a major source of forensic evidence. The increased dependence on DNA evidence by the police, prosecution and the defense has made the proper handling and processing of biological materials critical for justice.
In the process of handling evidence with DNA evidence in mind, Crime Scene officers and Property officers have three issues that should be addressed:
- Health and safety of persons handling the biohazardous evidence
- Maintaining the integrity of the evidence by reducing or elimination the risk of cross contamination
- Effective drying of the evidence to preserve DNA bearing material
Just what are the hazards involved with handling evidence bearing DNA evidence? In many cases the involved evidence is wet, generally with blood and body fluids (seminal fluid, salvia, and vaginal secretions). These fluids have the potential to contain various Biohazards (Hepatitis B, HIV, tuberculosis, parasites and others). While the major risk in handling this evidence is an accidental infection through the skin by (cuts and abrasions) or our mucous membranes (eyes, mouth, and nose). While many of these biohazards are not routinely transmitted through the air, evidence should be handled and stored in such a manner to ensure that dried blood, other fluids, bacteria or fungi does not become airborne so that it may be inhaled by the contaminated air spaces in our work environment.
Under federal guidelines issued by OSHA and the National Institute for Occupational Safety and Health (NIOSH) employees who work with Biohazard evidence must receive training on precautions against blood-borne pathogen exposure. Employers are required to conduct a risk assessment of your work area, provide employees with personal protective equipment, and provide employees with vaccination against hepatitis B infection at no cost to the employee. In January 1993 the Illinois department of Labor adopted the OSHA standard to cover public sector employee in Illinois.
But am I at risk for exposure? To learn if you are answer these simple questions:
- Am I assigned a task that requires me to contact human blood or other body fluids (with or without hand and face protection)?
- Have I ever had a splash or spill of human blood or body fluids on my skin or clothing?
- Is it possible that I could get human blood or body fluids on my skin or clothing by doing my regular job?
If you answered yes to any of these questions, you are at risk and need training in the proper procedures as required by the Blood borne Pathogen Standard. In addition to these concerns, employees of property/evidence storage rooms need to be concerned about the health of the air in their property rooms.
Property officers and Crime Scene officers may want to contact the National Institute for Occupational Safety and Health for a health evaluation of there evidence room(s), processing areas and drying spaces if they feel that the air quality of their work space may be less than ideal. While there are no specific ventilation standards for police property room(s) and evidence drying rooms, the American Society for Heating, Refrigerating, and Air-Conditioning Engineers has developed recommendations of
at least 10-12 air changes per hours, respectively; all air should be exhausted to the outside; that there should be no recirculation of air within the rooms and for rooms used to dry evidence these rooms should be negative pressure to adjacent areas( air flows into the room)
In order for Crime Scene officers and Property officers to reduce the risk that biohazards from drying evidence which may become airborne, appropriate filtration and venting systems must be established. One way to provide this is with the aid of Evidence Drying Cabinets. These cabinets are designed to air dry wet evidence and remove biohazards from the exhausted air with the aid of proper filtration. These cabinets are generally constructed of materials which permit decontamination by cleaning between uses, to prevent cross contamination. They also protect the drying evidence from cross contamination by officers working in the immediate areas by segregating the evidence in a closed container.
Generally there are two vents built into a drying cabinet, an intake and exhaust. There are multiple filters, a High Efficiency Particulate Air (HEPA) filter and carbon filter. These filters remove all biohazards and noxious fumes that may be present. A third filter is used in the intake vent to protect evidence from any airborne DNA or trace evidence that may be present in the area. When evaluating the HEPA filtration of a cabinet, it must meet the American Society of Heating, Refrigeration, and Air Conditioning Engineers Standard 52.2 (MERV 17-20) which requires that the filter remove particles 10 microns or larger to remove trace or DNA contamination.
DNA is degraded by UV light and bacteria. To stop bacteria, all moisture must be removed from your evidence before placing into a sealed evidence container. This is the role of the drying cabinet in addition to protecting the officers handling the evidence. This cabinet does not remove the requirement of officers to wear personal protective equipment while handling the evidence.
While these cabinets are not inexpensive, the safety of Crime Scene Officers and Property Officers and the integrity of evidence collected by the police for submission to the crime lab and its eventual use in the halls of justice make then required equipment in our evidence/property processing areas. The expense of the filters used by the cabinets is also an issue as yearly maintenance is necessary. Based on current research and industry experience, the average life of the HEPA (most expensive filter) is anywhere from 3 to 15 years or longer based on use. In fact the longer this filter is in service the more efficiently it work.
Flammable and Combustible Liquid Evidence and storage:
Crime Scene officers and Property officers deal with these materials often during a course of many different investigations from arson to drug cases to homicides and suicides. The safe storage of these materials in our property rooms is paramount to our safety in the workplace. Guidelines for the storage can be found under OSHA 29 CFR 1910.106 and the National Fire Protection Agency (NFPA) codes for the safe storage of these materials.
The use of Flammable Storage Cabinets is fundamental in the safe storage of these materials in our property/evidence rooms. While Federal guidelines are in place concerning the types of cabinets to be used and their construction many communities also have guidelines concerning the safe handling and storage of these materials. Some of the common features that these cabinets must have are:
- Self Closing doors
- Construction with 18 gauge steel
- Doors must have a three point latch
- Cabinet marked “Flammable- Keep Fire Away” Legend
These cabinets are used for safe storage of our evidence which in many arson cases is unlined paint cans and small fuel storage cans. These containers have a nasty habit of leaking or in the case of paint cans, if lids are not properly secured, popping off venting fumes into the area or rusting out leaking contents into our property rooms. This of course provides a real hazard for fires or explosions on our property storage areas. Property officers are advised to consult with their fire departments concerning the storage of flammable materials inside their buildings.
Flammable Gas Storage:
From time to time Crime Scene officers and Property officers become involved in cases that involve flammable gas and the containers holding these various gases. In light of the many different types of gases that come pressurized this article will deal with only LP gas (Liquefied petroleum) which we commonly see in propane tank for barbecue grills. Guidelines for the storage of these cylinders can be found under NFPA 58.
For the property officer NFPA 58 offers various important guidelines that must be followed some of which are:
- Storage in buildings shall not exceed 200 lb in one location.
- Cylinders in storage shall be located as to minimize exposure to excessive temperature rise, physical damage or tampering
- Empty containers which have been in LP Gas service shall be considered the same as full containers for the purpose of determining maximum quantities permitted for inside storage.
Crime Scene officers and Property officers should also be aware that these cylinders are sometimes used to store gases that were not intended, such as Anhydrous Ammonia. This use offers a serious storage issue as the material will break down the valve over time causing leaking of the contents.
Property officers have many unique storage problems with the various items taken in and with today’s extended time periods for the holding of property and evidence, it is more important than ever that Crime Scene/Property Officers stay abreast of safety issues and that they maintain their evidence storage areas in optimum conditions to insure that evidence is handled properly for our justice system and the officer is safe in this environment.
If you have any questions contact Jim Herman.
Mount Prospect Police Department
112 E. Northwest Hwy.
Mount Prospect, Il 60056