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.
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