Design of Control Rooms

The following items shall be addressed in the design of computer or control rooms:

  1. Proper space allocation for computer equipment, consoles, servers, storage area (for manual, documents, listings, maintenance equipment, etc.), environmental conditioning equipment (air and electrical power conditioning), fire protection equipment, and power distribution.

  2. Room accessibility for both operating and maintenance personnel. Guidance: The addition of interior windows, where appropriate, can reduce unnecessary traffic (e.g., room security, safety of personnel, etc. can be observed without entering the room).

  3. Space allocation for any potential expansion.

  4. Suitable access and easy loading areas for equipment.

  5. Adequate and convenient wire paths for installing signal, data, process control, safety, and associated power wiring to and from the computing systems.

Guidance: An overhead cable tray system provides the most convenient method for the installation of computer room wiring. Unrelated services, such as power conductors, water and steam piping, etc., should not be installed in the computer room or its included spaces and specifically should not be present overhead of data processing equipment or computer/control rooms. If unrelated services must be installed, the design should incorporate appropriate measures to protect the computer equipment.

  1. Data handling and analysis area. This is normally a small area for a conference table and chairs where computer printouts and reports may be laid out for analysis.

  2. Emergency lights, fire doors, power and air handling interlocks, etc.

  3. Radio-frequency interference (RFI) and electromagnetic interference (EMI) shielding, if required.

  4. Fire codes and requirements.

  5. Telephone and intercommunication systems.

  6. Adequate and proper lighting. Guidance: Two levels of lighting may be necessary; one for normal operation and one for maintenance. The Illuminating Engineering Society (IES) Lighting Handbook includes both quantitative and qualitative design data for various lighting needs. Where Computer Display Screens are in use, glare and reflection should be eliminated, so indirect lighting should be used where possible. Dimmer switches are sometimes used to reduce glare. Note, however, that SCR dimmer controls can be a source of RFI and should be avoided.

The computer/control room design, location, and access points shall be evaluated for the potential presence or introduction of contaminants through materials of construction, ventilation systems, transfer from adjacent areas or from workers and visitors. Any potential source of contamination that would affect the proper operation or reliability of the equipment shall be prevented by design, protective measures, or administrative procedures.

Guidance: The following should be taken into consideration to prevent the presence or introduction of contaminates within a computer/control room:

  1. Only materials that do not produce contaminants should be used in control/computer room construction. Sprayed-on acoustical ceiling and mineral-based drooped ceiling tiles should be avoided because they tend to flake. Glass fiber tiles that produce abrasive particles and floor covering that tend to crack or crumble should be avoided. Also, carpets should be of a quality that minimizes the release fibers and particulate. All exposed concrete should be sealed.

  2. Specially treated (impregnated) mats should be placed at each entrance to reduce the amount of dust tracked in by personnel.

  3. The use of a computer/control room as a gathering place should be avoided. However, the room may need to be used as a rally point for personnel in the event of a fire, explosion, or fume release. In such cases, provisions necessary for employee protection as well as for equipment protection should be considered.

  4. All floor or other cable trays should be capable of being kept clean and free of dirt, grit, or debris.

  5. Maintaining the computer/control room at a positive pressure may be considered as a means of preventing the entry of contaminates. In this application, special attention must be given to the quality of the inlet air and its source.

The potential for static electricity in computer/control rooms shall be eliminated to the maximum extent possible in room design and equipment location. Where a potential may exist for the generation of static electricity that could be detrimental to equipment operation, measures shall be taken to minimize the potential for static electricity generation. This may take the form of material and equipment prohibitions, temperature and humidity control, grounding methods, etc.

Guidance: The following should be taken into consideration to prevent static electricity in computer/control rooms:

  1. For control of static electricity, carpet is not the preferred floor covering for computer/control rooms. If carpet is used, steps should be taken to reduce static buildup. Certain carpets are given anti-static properties by the incorporation of metallic fibers during manufacture or treatment with anti-static agents. Anti-static sprays are available for use on existing carpet. Wax buildup on tile floors also increases surface resistivity and leads to static problems. The remedy is to forego waxing or to use a wax formulated for high conductivity.

  2. Furniture in the vicinity of digital equipment should be chosen carefully. Seat covers of plastic are normally more likely to generate static charges than cloth covers. Wheels and casters should contain conductive material and should be lubricated with graphite or conductive grease. Rubber or plastic feet should be avoided.

  3. Storage space may be required for operating supplies and storage media, spare parts and components, and backup software. These items may need protection from static electricity buildup both in storage and when handled. The manufacturer’s recommendations for both the use and storage of these items should be followed.

  4. Personnel grounding straps and insulating footpads may be necessary for especially sensitive processes or operations. Equipment sensitivity of this nature should be identified in design and operation documentation.

Guidance: Locating a computer/control room in an area subject to flooding should be avoided. Where this is not realistic for all possible conditions and flooding is possible, alternative measures should be taken, such as constructing a raised floor for the computer/control room. For raised-floor computer/control rooms, the installation of an alarm system initiated by water detectors located under the raised flow should be considered.