Trail of Evidence: Programming a Clear and Secure Pathway

Wed, 09/01/2004 - 4:00am
John W. Fueredi

The best time for users to communicate their needs to the design team is during programming; the phase in which the parameters of the project requirements are presented, discussed, and defined. Programming sets the stage for the design and construction. Users must come to the table with an understanding of what they want to achieve, an awareness of their budget, and what accreditation requirements need to be met. No matter how experienced the design team, users have the most amount of experience working in these spaces, and the detailed information they can provide regarding equipment, laboratory usage, and other requirements is invaluable. The higher the quality of information that is discussed during this stage, and the higher level of understanding reached between parties, the stronger the foundation will be on which to proceed. One of the best ways to do this is to follow a ìtrail of evidenceî (or circulation path). In this way, it is less likely for a vital piece of information to be omitted.

The following "trail of evidence" will highlight some specific steps related to security, contamination, and safety that should be clarified during the programming stage. These items are by no means all-inclusive, but they represent a good cross-section of issues that when programmed properly, will provide effective security, lowered risk of contamination, and a safer environment for personnel.

Access to the Site
The first thing to consider during programming is access to the site. Vehicular access to and around the site should be clearly identified and controlled. If possible, access from at least two directions should be provided. This may not be practical in some situations due to site or budget constraints, but it is encouraged because it allows better egress in emergency situations and serves as a backup if one access is blocked due to other contingencies.

For security reasons, the site should be divided into two zones: one for the public, and the other consisting of a secure zone for employee parking and other key building service functions such as HVAC, trash, and delivery areas. A secured gate or similar barrier should be used to separate employee from public parking. The gate should provide remote access for employees through a card swipe, camera, and/or intercom to the secure zone. Other delivery personnel who need occasional access to this area should be allowed through only after identifying themselves via the intercom or security camera.

Public parking should be accommodated close to the front entry but not too close as to pose a security concern. A good rule of thumb to follow is to keep parking at a minimum of 20 feet from the building with some site barriers in between to prevent vehicular penetration of the front door. This can be accomplished by the introduction of low planters or bollards constructed of concrete or steel and secured to foundations below grade.

It is also important to make as clear as possible which entrance is for the public. This can be done through the use of different building material around the public entrance vs. the secure entrance. More glass can be used in this area or, if brick or concrete block is used on the majority of the building, a contrasting natural stone facade can be used to highlight the public entry.

Delivery of Evidence
If evidence is to be brought through the public or ìfrontî door (and this often is the case), windows should be oriented to allow clear observation of the approaching vehicle and personnel. If night deliveries are anticipated, lighting for the parking lot and building exterior must be adequate enough to identify facial features of approaching people and minimize the possibility of vandalism. Security cameras can also be used to observe and document the approach. Remote entry systems minimize security risks at front and remote doors of the building. Exterior building materials should be vandal-resistant and promote the idea of a secure and strong environment. Windows at entry areas are recommended to be bulletproof glass and glazing. Typically, no more than nine inches of space should exist between mullions at exterior windows.

Upon entering the building, the walls of the entry or waiting area should be composed of bulletproof material. This can be achieved by masonry construction with cores filled with grout and steel reinforcing or through the use of sheet materials such as KevlarÆ on a stud wall. Windows and doors within this space must also be composed of bulletproof material. A fixed, transfer window with a transaction drawer is recommended in lieu of a sliding window to minimize the far too common occurrence of the window staying open.

The entry/waiting area should be separated from the circulation of the remainder of the building and card key access points should be placed at key points throughout the building. It is also a good practice to keep laboratories separate from administration areas with access control between the individual laboratories and examination areas. Depending on agency and user needs or protocol, these systems can range from a simple number keypad on the door to a more complex system with card keys and remote monitoring of occupant access.

Evidence Log-In
An Evidence Log-In room that is separated via a secure door from the public lobby area provides the opportunity to transfer evidence from the responsibility of the delivery person to the laboratory personnel. At this point, evidence is placed in a series of double-sided lockers that serve as pass-through. This prevents law enforcement officials from entering the laboratory area and creating possible contamination issues. There are numerous companies that provide evidence lockers of various combinations of sizes and shapes to accommodate everything from shotguns and large weaponry to small items. An important design consideration on the laboratory side is the possible installation of a series of sliding doors to cover the exposed locker doors. This would facilitate de-contamination and wipe-down procedures.

Another key component in minimizing potential for contamination from this point on is to program clear and directs paths from destination to destination. This would include minimizing the steps needed to get from ìpoint Aî to ìpoint Bî and planning direct paths that do not require investigative personnel to walk through potential areas of contamination such as break rooms while transporting evidence from lab to lab or from storage. A clear path also minimizes the risk of accidents such as slips or falls.

Upon retrieval from the locker, the evidence is logged in and a description of the contents is made. This typically takes place in an evidence description room or ERT. A biological safety cabinet is recommended in this space to protect technicians when they open up an evidence packet, and standard protocol should be followed. While the entire building should be maintained at a slightly positive pressure in order to keep outside contaminants and water penetration at bay, this room should be slightly negative so that air in the corridor flows into the Evidence Room and out through the safety cabinet. Proper room pressurization will keep evidence particulates safely inside the room.

Evidence can then go to a vault for storage or to an investigative exam area, laboratory, or specialty room for further research. The vault should be built as a six-sided, reinforced concrete box with controlled access for security purposes. By having concrete completely surround the space, intrusion is much less likely. Steel reinforcing should also be maintained through any openings such as HVAC or ductwork to prevent the possibility of intruders crawling into the vault.

Investigative and Laboratory Areas
Governing agencies have different policies in regard to observation and security, and these must be documented and communicated to the design team to ensure proper compliance. This communication is especially important during the programming process due to various protocols that can range from separate laboratories with common instrument rooms to open labs with secure exam rooms. One typical lab planning module that is used incorporates offices that flank a small corridor leading from the laboratory space to a main corridor. Windows can be installed from the main corridor to the office, and from the office to the laboratory. Glass is also provided in the doors to the laboratory. Windows can provide multiple benefits, including bringing daylight further into the interior of the building, allowing for observation of the laboratory personnel for safety concerns, and providing a barrier during guided tours of the facility.

Airflow within these spaces should also be pressurized so that the investigatory areas are negative to the outside corridor(s). Things to consider when setting the pressurization are: the number of fume hoods to be used, how often the hoods will be used, and the number of hours the room is expected to operate. Some specialized spaces may require laminar, or non-directional airflow, which basically washes gently down into the room in an even flow via laminar diffusers mounted on the air vents. This minimizes any potential draft or directional flow that could disturb trace evidence under inspection.

The equipment used in the laboratory and exam spaces must also be carefully accounted for in the planning of these spaces. Each piece of equipment has certain space and environmental conditions that must be maintained in order for it to operate properly. Power, air, water, and other utility requirements are usually listed in the equipment documentation and this information must be transmitted to the design team. Some equipment may generate heat that requires the HVAC system to provide additional cooling. Other equipment may have vibration sensitivities, therefore either an anti-vibration table or isolation of the structural slab may be required. The equipment must be allowed to work as intended to minimize any potential risk to the analysis of the evidence.

Large pieces of equipment such as a shoot tank are not exempt and they also have power and water requirements as well as potential sound isolation requirements. Sound attenuation, in addition to the use of concrete or concrete masonry unit wall construction, will help isolate sound from certain pieces of equipment. It is also important to strategically plan to have large equipment rooms located on an exterior wall. Not only will this minimize the noise impact on adjacent rooms but this location also facilitates the installation or removal of the large equipment without impacting the rest of the facility.

If the facility has an autopsy function, then numerous issues arise. If the program and budget allow, separate cold rooms should be provided for pre- and post-autopsy bodies. This will provide additional security and monitoring during shipping and receiving. The Autopsy Suite should be designed to provide adequate light during the procedure. Daylight is recommended to provide true color rendering during the investigation and documentation. Directional airflow should be coming into the Autopsy Room from an adjacent corridor or room. It is recommended to design a separate room within the Autopsy Suite specifically for decomposing or burn victims. This will help to control odors and other related issues. The directional airflow should be from the Main Autopsy Room into this separate room, in order to contain odors and particulates. Autopsy can be included within the rest of the laboratory building or separated via a covered walkway. Security must be maintained in numerous ways including access and handling and storage of evidence.

The Details (Finishes & Fire Protection)
The finishes of the investigative and laboratory rooms should be composed of material that can be cleaned thoroughly and often. This includes, but is not limited to, the ceiling material, paint, casework, benchtop material, and flooring. For example, painted gypsum wallboard ceilings may be desired in some spaces that have a higher potential for contamination. They are slightly more costly to install than a typical ceiling grid with acoustical panels, and access above the ceiling will have to be maintained through access panels, or by removing the light fixtures if they are ceiling mounted.

Fire protection must also be considered during the programming phase. Standard fire protection systems are water-based and, when the system activates, room equipment and finishes can be damaged. Other systems, such as the FM-200 system, will extinguish flames by chemicals, thereby minimizing equipment and finish damage. The chemical-based systems are more costly to install initially than a standard wet or dry-pipe water-based system; therefore, the frequency of their use should be carefully considered. Chemical-based systems can be limited for use in Instrument Rooms and Vault Storage rooms to minimize potential damage while at the same time minimizing the cost impact on the overall project budget.

Finally, the processing of hazardous materials upon receipt, analysis, and distribution must be thoroughly discussed and a consensus must be reached as early as possible in the planning phase. This could impact the design of floors, walls, ceilings, HVAC, and plumbing for the entire circulation path.

Get With the Program
Security, contamination, and safety issues affect everyone involved in a forensic investigation from lab personnel to law enforcement to alleged perpetrators of crime. Clearly, there are many issues that must be considered and the previously mentioned items are only a tip of the iceberg. Accreditation requirements and agency protocols will dictate how one would address a number of these issues and users are often the only people who can give practical input and insight to how various spaces should be arranged and how they will function within each space.

A design team should strive to provide an environment where the investigators or examiners do not have to worry about anything other than the task at hand. Experience is definitely important, but even more so, it is very important to find a design team that will listen to your concerns and go through the program with you step by step. Ultimately, their success will have a large impact on your success and the quality of work performed within a facility's walls. It all boils down to communicating the details.

NOTE: "Forensic Laboratories: Handbook for Facility Planning, Design, Construction, and Moving" (National Institute of Justice, 1998). This U.S. Department of Justice Handbook is a great reference for both user groups and design teams. It provides a very thorough guide for all of the phases to be considered from initial planning to final move-in details.

Trademark Information:Kevlar is a registered trademark of E.I. du Pont de Nemours and Company.


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