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Table of Contents:  

Section 6-1: HVAC Design Considerations

Section 6-1: HVAC Design Considerations
 
 6-1-00 Design Requirements
        10 Design Guidance 
        20 Design Information 
        30 Design Document Requirements

6-1-00 Design Requirements
 
A. Heating, Ventilation, and Air-Conditioning Systems for Research Laboratories and Animal Facilities:
Heating, ventilation, and airconditioning (HVAC) systems for Research Laboratories and Animal Facilities shall be designed to maintain the space temperature and humidity at the required set point.  These systems shall automatically adjust, as necessary, to respond to varying space cooling demands in laboratories and animal facilities.  Air-change rates, temperature and humidity shall be closely monitored and controlled on a continuous basis.  The System shall provide adequate ventilation to remove fumes, odors, airborne contaminants, and to safely operate fume hoods continuously.  They shall be designed to maintain relative pressure differentials between spaces to prevent of cross contamination.  Space background noise, generated by HVAC systems, shall be maintained within the levels prescribed within this document.  HVAC systems shall be reliable, redundant and operate without interruption while being efficient to operate, both in terms of energy consumption and from a maintenance perspective.
 
Federal energy conservation standards shall be achieved.  An energy monitoring and control system shall be provided.  This document outlines the basis of design and energy conservation compliance requirements.  During the design phase, studies shall be conducted to determine the feasibility of utilizing heat-recovery systems in research laboratory and animal facility buildings.
 
Laboratory spaces shall meet the requirements in the “Biosafety in Microbiological and Bio-medical Laboratories” published by Center for Disease Control and Prevention and NIH.
 
Animal Facilities shall meet the requirements in the “Guide for the Care and Use of Laboratory Animals” published by the Institute of Laboratory Animal Resources.
 
B. Outdoor Design Conditions:
All facilities shall be designed in accordance with the climatic conditions listed in ASHRAE Handbook of Fundamentals.  For summer conditions, use 0.4% column (9a / 9b) dry bulb (DB) / mean coincident wet bulb (MCWB) temperatures.  For winter conditions, use 99.6% column (3a) DB temperature.  Summer mean coincident wind speed (MCWS) shall be 0.4% DB column (11a).  Winter MCWS shall be 99.6% DB column (6a)
 
Sizing of evaporative type cooling towers shall be based on 1°C (2°F) higher than the WB temperature shown in the 0.4% column (10a) shown in the ASHRAE Handbook of Fundamentals.
 
All outdoor air-cooled condensing equipment shall be designed and selected on the basis of 35°C (95°F) ambient temperature.
 
B.1 Outdoor Design Conditions (Bethesda and Poolesville):
Equipment to be located in the main Bethesda campus and the Poolesville facility shall be designed in accordance with the following table:

Table 1 Outdoor Design Conditions
Season
Temperature °C (°F)
Wind Speed m/s (mph)
Summer
35.0 (95) DB, 25.6 (78) MCWB
5.4 (12)
Winter
- 11.6 (11) DB
4.8 (10)
Evaporative cooling
26.7 (80) WB
n/a







All outdoor air-cooled condensing equipment shall be designed and selected on the basis of 35°C (95°F) ambient temperature
C. Energy Conservation:
The A/E shall utilize the latest edition of the following energy codes and standards to design the exterior envelope and select HVAC systems, domestic water heating, electrical distribution and illuminating systems:
• ASHRAE Standard 90.1
• Energy Policy Act 2005.
• International Energy Conservation Code.
 
The Project Officer shall be notified when requirements of the energy conservation codes and standards cannot be satisfied due to program requirements.  New construction or major renovation shall require complete HVAC and energy simulation modeling.  Life cycle cost shall include capital cost factors for chillers and boilers as provided by NIH, as well as up to date energy costs.
 
D. Building Design Requirements:
HVAC systems shall maintain a safe and comfortable working environment and be capable of adapting to new research initiatives.  In addition, they shall be easy to maintain, energy efficient, and reliable to minimize lost research time.  HVAC systems for laboratory shall include central air-handling systems utilizing 100% outdoor air, which shall also provide adequate ventilation to offset exhaust air requirements.  Laboratory supply air shall not be recirculated or reused for other ventilation needs.
 
D.1 Indoor Design Conditions:
Occupied spaces, unless noticed otherwise, shall be designed to maintain the following temperature and humidity levels:

Table
2 Indoor Design Condition
Season
Temperature ˚C (˚F)
Relative Humidity %
Summer
23  + 1 (73 + 2)
50  + 5
Winter
21  + 1 (70 + 2)
30 + 5







D.2 Ventilation Rates:
Ventilation rates, unless noticed otherwise, shall be calculated to meet the cooling and heating loads and outdoor air requirements in accordance with ASHRAE design guidelines.
 
D.3 Heating Systems:
Heating, in NIH facilities, shall be provided by the use of steam and/or heating water systems.  Electric resistance heating shall NOT be used to provide heating in any NIH facility.  This includes builtin small electric heaters.
 
D.4 Cooling Systems:
Cooling, in NIH facilities, shall be provided by the use of chilled water/hydronic systems.  The use of air-cooled, self contained refrigeration systems for building cooling coils in air-handling systems shall be avoided unless chilled water is not available
 
D.5 Air Distribution Systems:
Supply, exhaust, and outside air shall be ducted  for all spaces, i.e., not taken through ceiling plenums, shafts, mechanical equipment rooms, corridors, or furred spaces.  The circulation of air directly between areas is not permitted, except into toilet rooms, locker rooms, and janitor’s closets.  Circulation may also occur between adjacent corridors into a negative pressure area or out of positive pressure areas.
 
Supply air distribution system shall be designed to minimize turbulence and to avoid having an impact on the performance of primary containment equipment such as chemical fume hoods and BSCs.
• Air outlets shall not discharge into the face of fume hoods or BSCs.
• Exhaust grilles and registers shall be located away from supply air diffusers in a manner that creates uniform, low velocity airflow across the room.
 
Plenums and air shafts for distribution of supply or exhaust air is prohibited in NIH laboratories and non-laboratory buildings.  Common outdoor air ductwork may be permitted for outdoor air intakes to multiple air-handling units due to space constraints and building configuration
 
Corridors shall be provided with conditioned air to maintain design temperatures and as required to make up air for negatively pressurized rooms opening directly to the corridor.  The quantity of conditioned air to the corridors shall be sufficient to maintain an overall positive building pressure
 
D.6 Anterooms:
Anterooms are typically located between the laboratory/isolation/protected room and the corridor.  The anteroom has two sets of doors, one door to the laboratory/isolation/protected room and one door to the corridor.  These two doors are interlocked so that only one door can be opened at a time.  Depending on the type of isolation required, the anteroom may be positive, negative or neutral.  The use and type of anterooms needs to be reviewed with NIH/DTR and NIH/DOHS.
 
Anterooms shall be provided with both supply and exhaust air grilles.  In addition, ante-rooms shall be provided with dedicated supply and exhaust air terminal units/boxes, which would permit the reconfiguration of the anteroom to accommodate program changes.
 
Typically, room differential pressure sensors are provided to monitor the pressure differential between the ante room, the laboratory/isolation/protected room and the corridor.  Room pressure differential is set to maintain a minimum of 2.5 Pa (0.01 in wg).  In some cases, room differential pressures may be as high as 12.5 Pa (0.05 in wg) or greater. Required room differential pressure needs to be reviewed by NIH/DTR and NIH/DOHS.
 
D.7 Program Equipment:
The selection and use of program equipment such as refrigerators, freezers, centrifuges, autoclaves, glassware washers, BSCs, fume hoods, etc. shall be established early in the design phase so that mechanical and electrical systems can be designed to support specific equipment requirements.
 
Program equipment shall comply with NFPA, OSHA, ANSI, NSF, NIH Fume Hoods Specifications requirements and other applicable standards.  Equipment selected shall not contain asbestos, lead or mercury.
 
The A/E shall obtain equipment requirements so that heat rejection, electrical usage, and other utility consumption data are included in the design of the HVAC systems.  Equipment space requirements shall be closely reviewed, and layouts shall allow for access to all piping, wiring, and ductwork connections, easy cleaning, maintenance and repairs.
 
Mechanical systems shall be designed and detailed so that they do not induce harm to or impede the operating efficiency of program equipment.  Pressure regulators, safety relief valves, gravity drainage facilities, temperature controls, and backflow protection devices shall be provided as required to protect equipment.
 
The building temperature control systems / Building Automation Systems (BAS) shall not be use to operate/control program equipment.  The complete control and operation/maintenance strategy for program equipment shall be closely reviewed against program requirements and with program users.
 
D.7.a Flammable Storage Cabinets:
Flammable storage cabinets shall not be vented and shall not be located underneath fume hoods.
 
D.7.b Corrosive Storage Cabinets:
A ventilated corrosive storage cabinet shall be provided in each laboratory.  Typically, these are located underneath fume hoods if present.
 
D.7.c Biological Safety Cabinets:
At NIH, biological safety cabinets (BSC) are typically Class II, Type A1 or Type A2, which shall NOT be hard ducted to the building exhaust air system, nor shall thimble connections be used.
 
BSC Class I, Class II-B1 and Class II-B2 are also used in NIH facilities.  These particular types of BSCs shall be hard ducted to a dedicated building exhaust air system.  In addition, BSC Class II-B1 and Class II-B2 shall be factory provided with means of shutting down the BSCs internal fan, whenever the static pressure, in the building exhaust air system connected to the BSC, drops below the required set point.  This is required to avoid having a positive BSC and positive exhaust ductwork.  This will prevent the release of hazardous products into the laboratory space.  Whenever multiple BSC of this type are connected to the same system, each BSC shall be provided with a dedicated exhaust type air terminal unit.  This will ensure the proper exhaust air amount is maintained through each BSC.  Building exhaust air systems serving these BSCs shall include provisions for increasing the systems static pressure to compensate for loading of the exhaust HEPA filters within the BSC, i.e. VFDs.
 
Rooms with ducted BSCs shall be provided with an additional room exhaust air grille connected to a dedicated exhaust air terminal unit.  Whenever the manual isolation damper associated with the BSC is closed, during the certification process of the BSC, the room ventilation system shall automatically adjust in order to maintain the negative pressure in the laboratory.
 
Regardless of class and type, all BSCs, at NIH, shall be provided with unit mounted HEPA filtration of the exhaust air prior to its discharge to the room space or to the outdoors.  All Class II BSCs shall comply with Standard NSF-49 developed by the National Sanitation Foundation (NSF).
 
Projects requiring the use of BSCs, regardless of class or type, shall be reviewed and approved by the NIH/DOHS and NIH/DTR during the design phase of the project.
 
D.7.d Fume Hoods:
Fume hoods may be variable air volume (VAV) or constant air volume (CV) type.  Although the use of VAV hoods is highly recommended, the decision shall be based on a comprehensive lifecycle cost analysis that accounts for all system features required by NIH.  Fume hoods to be used in NIH Facilities must meet the following criteria:

Table 3 Fume Hood Types
 
Fume Hood
Type
Nominal Hood Width mm (in.)
NIH Specification Section
Vertical Sash
Bench
1200 (48) – 1800 (72)
11810 (August 2004)
Horizontal Sash
Bench
1800 (72)
11820 (August 2004)
Combination Sash
Bench
1800 (72)
11830 (August 2004)






In addition, fume hoods shall comply with the testing requirements in the following NIH documents:
• NIH Specification Section 15991 – On Site Testing – Constant Volume Fume Hoods
• NIH Specification Section 15992 – On Site Testing – VAV Fume Hoods
• Appendix E.3 “Fume Hood Testing and Alarm System.”
 
Fume hoods shall be evaluated “AM” (as manufactured) under the ANSI/ASHRAE STD 110 and shall meet the following minimum performance ratings:
• Sash design position or positions: 457 mm (18 in.)
• Average face velocity: 0.51 m/s (100 fpm) (plus or minus 10%)
• Range of face velocities: No point in grid below 0.41 m/s (80 fpm) or above 0.61 m/s (120 fpm).  Actual not as measured.
• Average face velocity for sash at 50%: 0.41 (80) to 0.76 m/s (150 fpm).
• Average face velocity for sash at 25%: 0.41 (80) to 1.52 m/s (300 fpm)
• Performance rating: 0.05 ppm.
• Sash movement performance rating: 0.10 ppm.
• Response time for VAV hoods: Less than 3 seconds.
• Percentage of auxiliary air supply: 0% (auxiliary air hoods are not allowed)
• Static pressure loss: Not more than 124 Pa (0.5 in. wg) at 0.51 m/s (100 fpm) face velocity.
 
D.7.e Variable Air Volume Fume Hoods:
VAV fume hoods to be used in NIH facilities shall meet the following requirements:
• Fume hoods shall meet current NIH fume hood specifications.
• Fume hoods in non-containment type laboratories shall have no air-cleaning (HEPA or charcoal), except for radiological hoods.
• The laboratory shall remain under negative pressure with respect to the corridor or adjoining rooms even when the fume hood operates at the minimum exhaust air rate.  When the exhaust air quantity is reduced, supply air quantity shall be reduced by the same volume.
• Laboratory minimum ventilation requirement, ACH, shall be provided even when the fume hood(s) operate in the minimum exhaust air rate position.
• Airflow monitoring/alarm devices shall be installed at each fume hood to provide the user with operating information.  These devices shall monitor the following: (1) face velocity at the sash opening. (2) Sash position, and (3) pressure differential between hood and room.
 
Go to http://orf.od.nih.gov/PoliciesAndGuidelines/Bioenvironmental for additional information and applicable studies authored by Farhad Memarzadeh, Ph.D., P.E., of the National Institutes of Health and refer to the following articles:
• Methodology for Optimization of Laboratory Hood Containment - Volumes I and II
• NIH - Section 15991 - Onsite Testing for Constant Volume Fume Hoods - June 2006
• NIH - Section 15992 - Onsite Testing for Variable Volume Fume Hoods - June 2006
 
D.7.f Low Flow and Auxiliary Air Fume Hoods:
Low flow fume hoods may be used at NIH as long as they meet ALL the requirements as outlined in the NIH / ASHRAE 110 Modified Fume Hood Testing Protocol.  In addition, fume hoods shall comply with the testing requirements of the listed NIH onsite testing specification sections 15991, 15992 and Appendix E. 3 “Fume Hood Testing and Alarm System.”  The face velocity of low flow hoods should NEVER be below 0.41 m/s (80 fpm). 
 
Auxiliary air-type fume hoods shall NOT be used in any NIH facilities. In the event of a retro-fit application, the A/E shall investigate the capacities of the existing system exclusive of the auxiliary air, and laboratory supply and exhaust system characteristics. Once it has been established that the system can support the addition or replacement of an existing fume hood, this information shall be forwarded to the project officer for approval before the design is allowed to proceed.

D.8 Environmental Rooms:
Environmental rooms could be constant temperature cold rooms or hot rooms.  These rooms shall be located to accommodate service from outside the room space.  Temperature and humidity readouts shall be located inside and outside the room.  Ventilation of environmental rooms, such as cold rooms, which serve as occupied functioning laboratory spaces, shall be designed in accordance to the latest issue of ASHRAE Standard 62.  Environmental rooms used primarily for storage functions shall not require ducted ventilation air.
 
Cold rooms shall be provided with remote condensing units, which are not located directly above the room.  Floor mounted condensing units are preferred.  Associated, air conditioning components shall be located to accommodate service from outside the room.  Condensing units shall be water cooled.  If air cooled condensing units are used due to the lack of hydronic cooling media, then, the temperature of the area surrounding the condenser shall not be allowed to exceed 6°C (10°F) above the temperature of occupied adjacent areas.  Design consideration shall be given to ventilating and dissipating heat accumulation caused by equipment condensers.
 
D.9 Equipment Room Ventilation (Non-Lab Equipment Rooms):
Equipment rooms such as mechanical, electrical, boiler, chillers, pumps, air-handling units, fans, autoclave, and cage wash equipment, etc shall be heated and ventilated as follows:
• Heating shall be provided by the use of steam or heating water.  These rooms shall be heated to maintain a space temperature of 18°C (65°C).
• Ventilation systems shall be provided to maintain the space temperature to no more than 12°C (20°F) above outdoor air temperature.  Additional ventilation may be required to dissipate heat generated by the equipment located in the space.
• Minimum ventilation rates shall comply with local building codes and good Indoor air quality practices and requirements.
• Containment exhaust systems shall not be used to ventilate mechanical spaces.
 
Electrical rooms shall be ventilated to maintain a space temperature no more than 8°C (14°F) above outdoor air temperature.  Outdoor air into this room shall be filtered by using filters of 30% efficient filtration based on ASHRAE’s Standard 52, atmospheric dust-spot test efficiency.  If the electrical room is located within the building, and ventilation with outdoor air is not feasible, conditioned air shall be utilized to maintain the space to no more than 26°C (80°F).
 
Secondary switchgear rooms shall be provided with heating and cooling equipment to maintain space temperature between 18°C (65°F) and 26°C (80°F) and humidity level between 30 to 60% non-condensing to protect switchgear and electronic controls.  Switch-gear/transformer rooms located at the NIH Bethesda and Poolesville campuses shall be provided with temperature and humidity sensors.  These sensors shall be connected to the existing Supervisory Control and Data Acquisition (SCADA) system, which is the energy monitoring system for the campus.
 
Hydronic piping shall not be located with in electrical rooms and secondary switchgear rooms.  In the event that this can not be avoided, protection shall be added such as drip pans beneath all piping and equipment.  These drip pans shall be provided with water detection alarms connected to the BAS.  Hydronic piping and drip pans shall never be located over any electrical transformer, electrical panels, and switchgear.
 
Large equipment rooms, with significant ventilation requirements, shall be provided with multiple fans to avoid having areas with excessive accumulated heat.
 
Boiler rooms and rooms with combustion equipment shall be provided with a ventilation system that combines the ventilation requirements and the combustion air requirements.
 
Elevator machine rooms, telecommunication closets, fire alarm rooms, and other similar spaces with electronic equipment may require air conditioning instead of outdoor ventilation.  The A/E shall define criteria for these spaces and design accordingly.
 
D.10 Mechanical Equipment Location and Access:
Mechanical systems shall be designed in accordance with the following principles:
• HVAC, electrical, and plumbing systems shall be zoned to avoid overlapping of multiple systems over multiple buildings zones.  This will help reduce building complexity during shutdowns, building trouble shutting and building renovation.
• HVAC systems shall be designed such that there are specific building zones for smoke and fire control, piping, ductwork, conduits, cable trays, and lighting.  This is to include defined access and service areas/zones to all equipment.  These areas/zones need to be identified in the construction documents.  This needs to be particularly defined in mechanical rooms and interstitial spaces.
• Systems shall be selected to minimize the number mechanical components requiring service and maintenance.
• System components requiring frequent service and maintenance shall be located in equipment rooms or service areas and not above suspended ceilings or in occupied spaces.
• Clear and safe access shall be provided for servicing, removing, and replacing equipment.
• Sufficient instrumentation shall be specified for monitoring, measuring, adjusting, controlling, and operating at part load as well as full load.
• Equipment shall be selected and located for long-term durability, reliability, maintainability, and serviceability, so as to meet, at a minimum, the service life expectancy indicated by ASHRAE.
• Equipment shall not be located in confined, or with an access through, secured spaces.
 
E. Exhaust Air Systems:
Every exhaust air system is unique and requires specific review of issues such as air quantity, filtration, construction materials, type of discharge, controls, emergency power, hours of operation, etc.  In addition, exhaust air systems shall meet the following requirements:
• Exhaust air systems shall be designed to operate 24 hours per day, 7 days a week.
• Exhaust air systems shall be balanced with the AHU supply air systems.
• Capacity of exhaust air systems shall be increased by 20% to allow for future expansion.
• Electric motors and drives, associated with exhaust fans, shall be located out of the exhaust air stream.
• Electrical motors associated with exhaust fans shall be upsized by one motor size.
• Emergency Power - Exhaust air fans and systems shall be connected to the emergency electrical power system.
• Comply with NFPA 90A.  Exhaust air ductwork shall not be located in the same shaft with supply air ductwork and return air ductwork.
• Positive pressurized exhaust air ductwork should be avoided.  In addition, no positive pressurized ductwork segment, of any laboratory exhaust air system, shall be located in any occupied zone, including mechanical rooms.  Offices within mechanical rooms are classified as occupied spaces.
• Fume hood exhaust ductwork and exhaust fans shall be constructed of corrosion-resistant material, such as stainless steel, or be coated with a protective corrosion-resistant product such as epoxy phenolic, or vinyl selected to resist the anticipated corrosive fumes.
• When combining containment type equipment into a single exhaust air system, the A/E shall obtain approval from NIH/DOHS for exhaust air compatibility.
• Exhaust air discharge and stack shall be as per section 6-2, paragraph 6-2-00.C “Location of Outdoor Air Intake and Exhaust Discharge”
• Dampers – Smoke dampers and/or fire dampers shall NOT be installed in laboratory exhaust ducts serving fume hoods, BSCs, or other containment type equipment.
• Controls - Variable and constant air volume exhaust air fans serving multiple spaces shall be equipped with VFDs for control of air flow and duct static pressure.  Exhaust air from each laboratory and animal holding/support area shall be controlled by a dedicated pressure-independent air terminal air unit located in each room served.
 
E.1 Dedicated Exhaust Air Systems:
Research areas shall be provided with dedicated and separate exhaust air systems from non-research functions in the building.  In addition, the following systems shall be provided with dedicated and separate/independent exhaust air systems from any other exhaust air systems in the building:
• Isolation rooms.  Multiple isolation rooms may be combined into a single exhaust air system
• Laboratory general research areas
• Fume hood exhaust.  However, fume hood exhaust may be combined with laboratory general research exhaust but only after penetrating the last fire rated partition
• Exhaust air systems dedicated to serve BSCs
• Radioisotope/radioactive fume hoods
• Animal general research areas
• Cage washers.  In addition, certain cage wash equipment may require special space configuration.  The A/E shall discuss these systems with the animal program personnel.
• Ductwork serving central sterilization processing areas
• Ductwork serving areas with EtO sterilizers.  EtO exhaust air systems shall meet the installation requirements set forth by USEPA.  This system shall be provided with means of determining a failure of the exhaust air system and shutting down the EtO sterilizer.
• Ductwork serving spaces with battery-charging equipment
• Ductwork serving gas cylinders storage spaces.
• Ductwork serving pot washing equipment
• Toilet exhaust air systems.  This is to include janitor’s closets and locker rooms
• Any other function as designated by NIH/DOHS
 
E.2 Redundancy:
Exhaust air systems shall be arranged with multiple manifolded fans designed to achieve N+1 redundancy and maintain the exhaust air system fully operational, at all times.  Each manifolded fan shall be designed to be fully isolated while the overall system remains fully operational.  In the case of single fan systems, in addition to the main fan, a standby fan shall be provided.  The A/E shall review redundancy requirements for each particular system with the program user and the NIH/DOHS.  Regardless of the system size, the following exhaust systems shall be provided with an N+1 redundancy:
• Isolation rooms
• Laboratory general research areas
• Fume hood exhaust
• Radioisotope/radioactive fume hoods
• Animal general research areas
• Cage washers
• Any other function as designated by NIH/DOHS
 
E.3 Isolation Rooms:
Exhaust air system for isolation rooms shall be a dedicated system capable of serving negative pressure (normal isolation) rooms or positive pressure (reverse isolation) rooms.  Exhaust air systems for isolation rooms dealing with highly infectious pathogens may require bag-in/bag-out HEPA filtration.  The A/E shall review filtration requirements for each particular system with the program user and the NIH/DOHS.  If HEPA filtration is not required, the system shall be designed with provisions for adding the HEPA filtration in the future.  This dedicated exhaust air system shall include: pressure-independent constant-volume air terminal units, roof-mounted exhaust fans, VFD for filter loading and/or for multiple rooms applications, exhaust stacks, bag-in/bag-out HEPA filters, etc.
 
E.4 Exhaust Air Filtration:
Generally, exhaust air does not require filtration or scrubbing.  However, in special laboratories, such as laboratories using radioisotopes or certain hazardous chemicals, the exhaust air may require special filtration before being discharged to the outdoors.  The A/E shall consult with NIH/DTR, NIH/DOHS, and NIH/ Radiation Safety Branch for specific requirements.  These exhaust air systems shall include provisions for accounting for filter loading and adjusting the system static pressure in order to maintain the required air flow amount.  Whenever filters or scrubbers are required, they shall be located as close to the source of contamination as possible while maintaining ready access for installation, monitoring, maintenance, testing, and filter replacement.
 
E.5 Wet Exhaust:
Wet exhaust air from areas such as sterilizers, autoclaves, glass washers, cage washers, and pot-washing equipment, etc shall be captured by using canopy-type stainless steel hoods at each equipment entrance and exit. 
Canopy hoods shall meet the following requirements:
• The canopy hood shall be located above the door to load and unload the equipment.  In the case of double sided equipment, a canopy shall be placed above each equipment door.
• Exhaust air shall be at a minimum rate of 0.254 m/s (50 fpm) capture velocity at the face of the canopy hood.
• Canopy hood design shall include a drip ledge to collect condensate steam.  In large canopy hoods, collected condensate steam shall be piped to the nearest floor drain.
• Wet exhaust systems shall be separated from other exhaust air systems.
• Ductwork shall be pitched back toward the canopy hood.
• Canopy exhaust hoods shall be installed above steam vapor and heat generating equipment in both the “dirty” and the “clean” sides of the equipment.
For additional information refer to Appendix E.5 “Calculation Protocols for Canopy Hoods over Autoclaves: NIH Local Exhaust Ventilation (LEV) test Protocol”
 
F. Design Requirements for Research Laboratory spaces:
HVAC systems for research laboratories shall be independent from other HVAC system in the building.  These systems shall maintain a safe and comfortable environment, be adaptable, and be capable of maintaining the required environmental conditions.
 
Redundancy – Since research laboratories may conduct studies of long duration, which need to be performed under consistent environmental conditions in order to achieve repeatable results, the failure of the HVAC system is unacceptable. Central HVAC systems shall be provided with multiple air handling units and exhaust fans to provide redundancy and improve reliability.  These systems shall be designed to include manifolded air-handling units to achieve N+1 redundancy and maintain operation at all times.
 
F.1 Laboratory Indoor Design Conditions:
HVAC systems to serve research laboratories shall be designed to maintain the following indoor temperature and humidity conditions at all times:

Table
4 Indoor Design Conditions for Laboratories
Season
Temperature ˚C (˚F)
Relative Humidity %
Summer
23 + 1 (73 + 2)
50 + 5
Winter
21 + 1 (70) + 2)
30 + 5





F.2. Laboratory Ventilation Rates:
Ventilation rate, for research laboratories, is typically driven by three factors: fume hood demand, cooling loads, and removal of fumes and odors from the laboratory work area.  The minimum outdoor air ventilation rate for laboratory space is 6 air-changes per hour, regardless of space cooling load.  This minimum ventilation rate shall be maintained at all times.  Some laboratories may require significantly higher ventilation rates to support fume hood demand or to cool dissipated heat from laboratory instruments and equipment.
 
Air Filtration – Air handling units to serve laboratory spaces shall be provided with filters up-stream the supply air fans.  These filters shall be 30% efficient pre-filters and 95% efficient after-filters. HEPA final filtration shall be provided in AHU to serve special laboratories where research materials are particularly susceptible to contamination from external sources.  HEPA filtration of the supply air shall only be considered necessary for critical applications.  It is preferred that BSCs, which include HEPA filtration, be used rather than providing HEPA filtration for the entire room.  The A/E shall confirm with NIH/DTR and NIH/DOHS for the need of HEPA filtration in laboratories.
 
F.2.a Ventilation in Laboratories working with Laser Equipment:
Rooms where laser equipment is used shall be properly ventilated to avoid buildup of ozone generated from laser and mercury lamps.
 
F.3 Air Distribution:
Laboratory spaces shall be designed with special attention to air quality, room acoustics, supply air temperature, supply air humidity, airflow quantities, air velocity, and air diffusion and distribution within the space.  In addition, space air distribution shall meet the following requirements:
• Distribution shall prevent cross contamination between individual spaces, air shall flow from areas of least contamination to areas of higher contamination potential, i.e., from "clean" to "dirty" areas.
• Air supply devices shall be located at ceiling level or close to ceiling level if located on sidewalls. Air distribution and diffusion devices shall be selected to minimize temperature gradients and air turbulence.
• Supply air devices shall be located away from fume hoods and BSC.
• Large quantities of supply air can best be delivered through perforated plate air outlets or diffusers designed for large air volumes.
• Space temperature and humidity shall be consistent in each individual room.  Space temperature shall be monitored in each individual room
• Each lab space shall be provided with dedicated temperature controls.  This shall include the used of dedicated air-terminal units for the supply air and the exhaust air.
 
F.4 Relative Room Pressurization:
Laboratories shall be designed and air balanced so that air flows into the laboratory from adjacent (clean) spaces such as: offices, corridors, and non-laboratory spaces.  The control of airflow direction, within research laboratory spaces, helps reduce the spread of odors, toxic chemicals, and air-borne contaminants as well as protect personnel from toxic and hazardous substances, and protect the integrity of experiments.  In these facilities, the use of the once-through air-flow principle is based on: (1) Use of 100% outdoor air to provide all the room air to be exhausted through laboratory spaces and laboratory containment equipment; (2) Size the exhaust air system to handle the simultaneous operation of all laboratory spaces and all laboratory containment equipment, and (3) Directing air flow from low hazard areas to high hazard areas at all times.  Air supplied to the corridor and adjacent clean spaces shall be exhausted through the laboratory to achieve effective negative pressurization.  Construction Documents shall include a complete start-up and commissioning plan including procedures that address indoor air quality requirements.
 
Laboratory spaces shall remain at a negative air pressure in relation to corridors and other non-laboratory spaces.  Typically, these systems are designed to maintain 47 L/s (100 cfm) air flow from the corridor into each lab module.  Administration areas in laboratory buildings shall always be positive with respect to corridors and laboratories.  Supply air distribution for corridors shall be sized to offset transfer air to laboratories while maintaining an overall positive building pressure.
 
Amount of supply air flow to laboratory spaces is to meet the cooling loads requirements as well as the exhaust air requirements.  Typically, the exhaust airflow requirements would exceed the cooling loads requirements.  In these situations, the supply air flow would need to be increased to makeup the difference between the cooling air flow and the required exhaust air flow.  In cases where the cooling load airflow requirements exceed the required exhaust air rate requirements, supplemental cooling units may be required.
 
Special laboratories such as, genome DNA processing rooms, tissue culture laboratories, clean laboratories, etc, may require a different type of relative room pressurization.  Some special laboratories may require positive air pressure in relation to adjacent spaces.  In these cases, the use of a personnel entry or anterooms shall be used.  These special applications need to be reviewed by NIH/DTR and NIH/DOHS.
 
Loading docks and receiving areas shall be maintained as positive to the outdoors and negative to the building to prevent the infiltration of vehicle fumes.
 
G. Design Requirements for Animal Research Facilities:
HVAC systems for animal research facilities shall be independent from other building HVAC systems.  These systems shall maintain a safe and comfortable environment for animals, be adaptable, and be capable of maintaining environmental conditions in any of the holding rooms for any of the species anticipated to be housed in the facility.
 
Redundancy – Since most animal studies are of long duration, they shall be performed under consistent environmental conditions in order to achieve repeatable results.  Thus, the failure of the HVAC system is unacceptable. Central HVAC systems shall be provided with multiple air handling units and exhaust fans to provide redundancy and improve reliability.
 
Some rooms may be designated as “hooded rack” type rooms having a housing chamber with sash fronts similar to a walk-in fume hood or individual air recycle systems of the laminar-flow type. Unit directional flow, laminar-flow type systems for any of these rooms may also be required.
 
G.1 Indoor Design Conditions:
Animal support facilities shall be designed to meet the following indoor temperature and humidity conditions:

Table
5 Indoor Design Conditions in Animal Support Areas
Season
Temperature ˚C (˚F)
Relative Humidity %
Summer
23 + 1 (73 + 2)
50 + 5
Winter
21 + 1 (70 + 2)
30 + 5








Ideally, all animal-holding rooms shall be capable of housing all type of species.  The HVAC system shall also be capable of maintaining the full range of requirements for all anticipated animal populations. The temperature range required to accommodate most commonly used research animals is 18˚C (65˚F) to 29˚C (84˚F) controlled to plus or minus 1˚C (2˚F).  The ranges do not represent acceptable fluctuation ranges.  The humidity shall be between 30% and 70% and normally controlled to 50% plus or minus 5%. These ranges can be narrowed when the species anticipated have similar requirements.
 
Animal-holding areas shall be maintained, at the design conditions, at all times. Design conditions shall be satisfied under all load conditions between the various holding areas. 

Table
6 Indoor Design Conditions in Animal Housing Facilities
Species
Temperature (1) ˚C (˚F)
Relative Humidity %
Mouse
18 (65) – 26 (79)
35 + 5 (3,4)
Hamster
18 (65) – 26 (79)
35 + 5 (3,4)
Guinea Pig
18 (65) – 26 (79)
40 – 70
Rabbit
16 (60) – 20 (68)
40 – 70
Dog and Cat
16 (60) – 29 (84)
30 – 70
Nonhuman Primate
16 (60) – 29 (84)
45 – 70
Chicken
16 (60) – 27 (80)
45 – 70
Amphibians
Note 2
Note 2
Aquatics (zebra fish)
26 (78) - 29 (84)
50 - 70
Reptiles
Note 2
Note 2
Insects
Note 2
Note 2


















Notes:
(1) The A/E has the option of either designing for the full range listed in each animal species or, may after consultation with the facility users, choose a narrower range expected to meet present and all known future requirements.
(2) To be determined by the user.  These space temperatures are research dependent.
(3)  Refer To: “Ventilation Design Handbook on animal research facilities using static microisolators”; Volumes I and II, November 1998, Farhad Memarzadeh, PhD, P.E., NIH – Office of the Director, ORF Publication, Bethesda, MD
(4)  Refer To ASHRAE 2005 Fundamentals Handbook, Chapter 10 “Environmental Control For Animals and Plants”

Some laboratories within the animal facility conduct special research requiring unique temperature and humidity ranges and control. These special cases shall be evaluated and provided for on a case-by-case basis. The HVAC system shall be designed to accommodate these unique conditions as they occur.
 
G.2 Ventilation Systems in Animal Research Facilities:
Ventilation systems in animal research facilities shall be designed in consideration of many factors such as:
• Animal species and their population
• Required minimum ventilation rate
• Recommended ambient temperature and humidity
• Heating and cooling loads within animal rooms
• Heat gain produced by the animals
• Use of microenvironments and the different ventilation methods in animal cages
• Use of fume hoods and/or BSCs
• Animal cage cleaning methods
• Animal examinations method
• Airborne contaminants
• Institutional animal care standards, as applicable to animal facilities.
 
Ventilation rates, within each individual room, may vary depending of the actual animal specie in each room.  The following table shows a typical ventilation rates for various animal species:

Table
7 Ventilation rates in Animal Research Facilities (1)
  
Facilities
Minimum Air Changes per Hour (2) ACH
Small Animal, Static Cage/Rack
15
Small Animal, Ventilated Cage/Rack
10
Large Animal
15
Aquatics (zebra fish)
6 (3)
Office / Administration Support 
6 (4)
Laboratories
6










Notes:
(1) Ventilation rates refer to 100% outside air
(2) Or higher to support fume hood and BSC demands and high heat loads
(3) Typical ventilation rate ranges from 6 to 9 air changes per hour
(4) Or 9 L/s (20 cfm) per person, whichever is greater
 
Ventilation systems in animal research facilities shall meet the following requirements:
• Rooms shall be designed to avoid drafts which could adversely affect animal health
• Reduce airborne animal hair and particulate count.
• Minimum ventilation rate for animal housing and treatment facilities shall be in accordance with ASHRAE HVAC Applications Handbook, chapter “Laboratories”, ASHRAE Fundamentals Handbook, chapter “Environmental Control for Animals and Plants”, and the Institute of Laboratory Animal Resources "Guide for the Care and Use of Laboratory Animals"
• Air recirculation within animal facilities is prohibited.
 
Air filtration - In addition to the typical pre-filtration and filtration normally used in air-handling units, final filtration is generally provided in air-handling units serving animal areas.  This final filtration is to remove particulate and other contaminants, which can be generated within the air-handling equipment itself.  Filter efficiency of final filters varies from 95% to 99.99% (HEPA).  The Design Engineer shall review the specific Program of Requirements to establish specific filtration criteria.
 
G.2.a Microenvironments:
Ventilation rates in animal facilities are typically 10 to 15 outdoor-air changes per hour (ACH).  This practice has also been used for secondary enclosures (animal cages/microenvironments) and is considered to be an acceptable general practice.  Although it is effective in many animal-housing settings, this practice does not take into account the range of possible heat loads; species, size and number of animals involved; type of bedding or frequency of cage-changing; the room dimensions; or the efficiency of air distribution from the secondary to the primary enclosure (animal room).  In some situations, high flow rates may over ventilate a secondary enclosure that contains few animals and waste energy or by under ventilating, a secondary enclosure that contains many animals, which would allow heat and odor to accumulate.
 
For additional information, refer to ASHRAE, 2007, HVAC Applications handbook and to the Institute of Laboratory Animal Resources, NRC, 1996, Guide for the Care and Use of Laboratory Animals.
 
System connections to microenvironments shall be designed to maintain manufacturer’s specified criteria.  For rooms housing animal ventilated racks, it is recommended, that the ventilation system be sized by adding the airflow required for the animal cooling/heating loads, of fully loaded ventilated racks, to the airflow required for other room cooling/heating loads such as lights, people, equipment, etc.  This airflow shall be compared with the manufacturers recommended airflow and the larger airflow amount shall be used.  The A/E shall evaluate all anticipated combinations of animals and cage systems; calculate supply air demands for make-up air, ventilation rates, cooling demand and heating demand; and design for whichever criteria results in the highest airflow demand.
 
Go to http://orf.od.nih.gov/PoliciesAndGuidelines/Bioenvironmental/  for additional information and applicable studies, authored by Farhad Memarzadeh, Ph.D., P.E., of the National Institutes of Health, and refer to the following articles:
• Comparison of Environment and Mice in Static and Mechanically Ventilated Isolator Cages with Different Air Velocities and Ventilation Designs
• Investigation of Static Microisolators in Wind Tunnel Tests and Validation of CFD Cage Model
• Mass Generation Rates of Ammonia, Moisture, and Heat Production in Mouse Cages with Two Bedding Types, Two Mouse Strains, and Two Room Relative Humidities
• Ventilation Design Handbook on Animal Research Facilities Using Static Microisolators -Volumes I and II
• Ventilation Design in Animal Research Facilities Using Static Microisolators
 
G.3 Room Air Distribution:
Animal facilities shall be designed with special attention to air quality, room acoustics, supply air temperature, supply air humidity, airflow quantities, air velocity, and air diffusion and distribution within the space.  In addition, space air distribution shall meet the following requirements:
• Distribution shall prevent cross contamination between individual spaces, air shall flow from areas of least contamination to areas of higher contamination potential, i.e., from "clean" to "dirty" areas.
• Air supply devices shall be located at ceiling level or close to ceiling level if located on sidewalls. Air distribution and diffusion devices shall be selected to minimize temperature differentials in the space.
• The A/E shall ensure that the system does not create drafts on the animals and that the airflow is uniform in nature.
• Where required, a provision shall also be made for high exhaust to be activated for directly exhausted racks to maximize space flexibility.
• Individual room temperature sensors, for animal holding rooms, shall be located inside the general exhaust ductwork from each room at an accessible location near the room envelope.
• Space temperature and humidity shall be consistent in each individual room.  Space temperature shall be monitored and recorded in each individual room
 
Go to http://orf.od.nih.gov/PoliciesAndGuidelines/Bioenvironmental/ for additional information and an applicable study, authored by Farhad Memarzadeh, Ph.D., P.E., of the National Institutes of Health, and refer to the following article:
• Analysis of Air Supply Type and Exhaust Location in Laboratory Animal Research Facilities Using CFD
 
G.4 Exhaust Air Systems:
Animal room exhaust shall be filtered at the room exhaust grille with a rough filter to capture hair and dander.  This is to be accomplished by providing air filter tracks in the face of the room exhaust air grille.  Filters shall be 25 mm (1-in.) throwaway type.  Whenever feasible, exhaust air grilles with face mounted air filters shall be located at 300 mm (12-in.) above finished floor.
 
Exhaust air from animal rooms shall be discharged outdoors without recirculation into any other room.  For protection of personnel and to minimize the potential for cross contamination of animals, the direction of airflow shall be inward to the animal rooms, at all times.  Where protection of the animals from possible contamination is required, consideration should be made of providing ventilated airlocks for the animal rooms.  The use of filtered isolation cages may also be considered.  Architect/Engineers should consult with animal facility personnel with regard to the specific requirements for protection of animals.
 
In cage wash facilities, the “dirty,” “clean,” and cage washing equipment, including associated mechanical supporting equipment area, shall be physically separated from each other, including equipment pits.
 
G.4.a Necropsy and Pathology work:
Necropsy and pathology work with infectious agents in animal research facilities shall be done within BSCs or on downdraft tables.  The use and the design of downdraft tables shall be approved by NIH/DOHS.  Downdraft tables shall provide an average downdraft of 0.25 m/s (50 fpm) at a height of 125 mm (5 in.) over the entire top surface of the table. [For detailed calculations on downdraft table particle capture efficiency –See Appendix H]
 
G.5 Relative Room Pressurization:
Relative pressurization within animal facilities is a series of complex relationships. Some of these relationships may change as research and animal populations change. The HVAC system shall be capable of maintaining these relative pressure relationships and capable of adapting as facility utilization changes.  In addition, animal spaces shall be protected against contamination from outside sources, including particulates brought in from outside by the HVAC air flow.
 
Animal rooms shall remain at a negative air pressure relative to clean corridors and other non-animal spaces.  Clean areas of the facility including: the clean side of cage and rack washing, clean corridors, bedding dispensing, and feed preparation areas shall be positive to animal holding spaces and soiled areas.  Soiled areas such as dirty service corridors, soiled side of cage and rack washing, and decontamination and waste-holding areas shall be maintained at a negative pressure.
 
Some areas have special pressurization requirements and shall be addressed individually. By NIH/DTR and NIH/DOHS
 
Animal-holding areas for transgenic or immunosuppressed populations shall be maintained at a positive pressure and may require special filtration of supply air. When these rooms are maintained at positive pressure, an anteroom or similar feature shall be placed between the animal room and the corridor.
 
Potentially infectious populations shall be maintained at a negative pressure to prevent contamination of other animal populations. Depending on the nature of the infectious agents involved in the research, these areas may be required to meet the design criteria for biohazard containment facilities.  The use of anterooms or microisolator housing units may be required to maintain these special conditions.
 
The pressure relationships for animal care areas including treatment rooms, procedure rooms, necropsy rooms, and surgical areas require investigation by the design team with the facility user to determine project-specific requirements. The HVAC system shall be adaptable so that pressure relationships can be modified as required over the life of the facility.  These applications need to be reviewed by NIH/DTR and NIH/DOHS
 
Dirty elevator shafts shall have negative air pressurization in relation to all surrounding areas.
 
6-1-10 Design Guidance
 
A. Heating and Cooling Load Calculations:
Complete heating and cooling load calculations and a vapor drive study shall be prepared for each space within a design program and presented in a format similar to that outlined in the ASHRAE Handbook of Fundamentals.  Heating and cooling load calculations are required for all projects to facilitate review and provide a reference for system modifications.  Individual room calculations shall be generated and summarized on a system basis and presented with a block load to define the peak system load.  Load summary sheets shall indicate: individual room’s area, supply air quantity, L/s per m2 (cfm), ACH, and corresponding exhaust air quantity.  Calculations shall include, but are not limited to: indoor and outdoor design parameters, heat gains and heat losses, supply and exhaust requirements for central systems, and for each area of the facility, humidification and dehumidification requirements, and heat recovery.
 
B. Occupancy Loads:
The A/E shall base HVAC load calculations on the expected occupancy in each space and the activity level as per ASHRAE Fundamentals Handbook.
 
B.1 Animal Room Cooling Loads:
Heat generation from animals for the purpose of HVAC load calculations shall be as listed in the ASHRAE Fundamentals Handbook.
 
B.2 Animal Density:
A typical 3 m (10 ft.) by 7 m (23 ft.) animal holding module shall be designed to the following animal population density:

Table
8 Design Animal Density

Species
Animals per Rack
Racks per Module
Animals per
Module
Mouse
              300
5
              1,500
Rat
                90
5
                 450
Guinea pig
                40
5
                 200
Rabbit
                  8
5
                   40
Cat
                  8
5
                   40
Nonhuman primate
                  8
5
                   40















C. Laboratory Equipment Cooling Loads:
The central HVAC system shall provide, as a minimum, a cooling capacity for 1,892 W (6,455 BTUH) (sensible heat) for laboratory equipment in a typical 22 m2 (237 ft2) laboratory module or cooling for the actual calculated load, whichever is greater.  The A/E shall make a detailed and complete inventory of all laboratory equipment scheduled for installation in each space and determine the projected equipment load requirement using estimated utilization factors.  Equipment utilization factors shall be indicated in the Basis of Design report.  The A/E shall evaluate the following rooms used for laboratory support, often having higher than normal cooling loads, as well as evaluate the use of supplemental cooling units to remove excessive sensible loads affecting these areas, while maintaining minimum ventilation requirements:
• Common equipment rooms.
• Autoclave rooms.
• “Clean” and “dirty” cage wash rooms.
• Glassware washing rooms.
• Darkrooms.
• Special function rooms.
• Electron microscope.
 
C. Lighting Loads:
Lighting loads shall not exceed the values listed below.  The A/E shall base HVAC load calculations on actual lighting loads.

Table
9 Maximum Lighting Loads

Space type
Task Lighting
W / person
Room Lighting (1)
W / m² (W / ft ²)
Biomedical Laboratories
250
27 (2.5)
Animal Holding Areas
250
16 (1.5)
Animal Procedures
250
27 (2.5)
Offices
250
14 (1.3)
Corridors
N/A
11 (1.0)










Notes:
(1) Electrical power for room lighting load does not include electrical power for task lights

6-1-20 Design Information
 
A. Reference Design Guidelines for the HVAC Designer
The NIH is a progressive and dynamic biomedical research institution where state-of-the-art medicine is the standard practice. To support state-of-the-art research and medical care, the facilities must also be state-of-the-art. It is the NIH intent to build and maintain the physical plant and facilities in accordance with the latest standards. It has been the NIH experience that renovation/rehabilitation of existing facilities do not lend themselves to incorporating the “latest” standards of the industry, primarily due to outdated and inadequate mechanical systems or because the planned function is incompatible with the original criteria of the facility.
 
The Architect and Engineer (A/E) will be alerted to this type of situation and make an evaluation early in the design stage to determine the feasibility of implementing the latest standard. The A/E should document such findings, provide recommendations, and report them to the Project Officer for a decision on how to proceed.
 
The A/E design firm should use and comply with, as a minimum, the latest issue of the following design and safety guidelines. In addition, the A/E should use other safety guidelines received from the NIH Project Officer or as required by program.  The A/E should utilize the latest versions of guidelines available at the time the project proceeds with schematic design.
 
The design and safety guidelines include but are not limited to the following:
• The International Building Code
• The International Mechanical Code
• The International Energy Conservation Code
• National Fire Codes, all volumes National Fire Protection Association, (NFPA), 1 Bat-terymarch Park, Quincy, MA 02269-9101.
• ASHRAE Handbooks and Standards  American Society of Heating, Refrigerating, and AirConditioning Engineers (ASHRAE), Inc.: 1791 Tullie Circle, N.E., Atlanta, GA 30329.
• Industrial Ventilation:  A Manual of Recommended Practice for Design, American Conference of Government Industrial Hygienist (ACGIH), 1330 Kemper Meadow Drive, Cincinnati, Ohio, 45240
• Occupational Safety and Health Standards, CFR 29, Part 1910 U.S. Department of Labor, Occupational Safety and Health Administration, (OSHA)
• Biosafety in Microbiological and Biomedical Laboratories.  U.S. Department of Health and Human Services.  Centers for Disease Control and Prevention and the National Institutes of Health.  Washington, DC.
• Primary Containment for Biohazards:  Selection, Installation and Use of Biological Safety cabinets.  U.S. Department of Health and Human Services.  Centers for Disease Control and Prevention and the National Institutes of Health.  Washington, DC.
• Guide for the Care and Use of Laboratory Animals.  Institute of laboratory Animal Resources, Commission on Life Science, National Research Council.  National Academy Press, 2101 Constitution Avenue, NW, Washington, DC 20418
• Guidelines for Design and Construction of Health Care Facilities.  The American Institute of Architects Academy of Architecture for Health with the assistance from the U.S. Department of Health and Human Services.  The American Institute of Architects, 1735 New York Avenue, NW, Washington, DC 20006.
• Standard NSF/ANSI 49.  Class II (laminar flow) biosafety cabinetry.  National Sanitation Foundation (NSF).  789 N. Dixboro Road, Ann Arbor, MI 48105
• Guidelines for Laboratory Design: Health and Safety Considerations, L.J. DiBerardinis, J.S. Baum, M.W. First, G.T. Gatwood, and A.K. Seth.  John Wiley & Sons, Inc, 111 River Street, Hoboken, NJ 07030-5774
• Analysis of Air Supply Type and Exhaust Location in Laboratory Animal Research Facilities Using CFD, Andrew Manning, Ph.D., Farhad Memarzadeh, Ph.D., P.E., Gerald Riskowski, Ph.D., P.E., ASHRAE Transactions 2000, Volume 106, pt 1, DA-00-14-3, Pages 877-883
• Thermal Comfort, Uniformity, and Ventilation Effectiveness in Patient Rooms: Performance Assessment Using Ventilation Indices, Farhad Memarzadeh, Ph.D., P.E., Andrew Manning, Ph.D., ASHRAE Transactions 2000, Volume 106, pt 2, MN-00-11-3, Pages 748-761
• Methodology for Optimization of Laboratory Hood Containment  Volumes I and II, November 1996, Farhad Memarzadeh, PhD, P.E., NIH – Office of the Director, ORF Publication , Bethesda, MD
• Handbook: Assessing the Efficacy of Ultraviolet Germicidal Irradiation and Ventilation in Removing Mycobacterium Tuberculosis, September 2000, Farhad Memarzadeh, PhD, P.E., NIH - Office of the Director, ORF Publication, Bethesda, MD
 
In addition, refer to the following documents by using the associated internet links:
• Guidelines for Research Involving Recombinant DNA Molecules.  U.S. Department of Health and Human Services, U.S. Public Health Service, National Institutes of Health, Bethesda, MD
NIH  Guidelines for Research Involving Recombinant DNA Molecules
• Laboratory Safety Monograph A Supplement to the NIH Guidelines for Recombinant DNA Research.  U.S. Department of Health and Human Services, U.S. Public Health Service, National Institutes of Health, Bethesda, MD.
NIH  Laboratory Safety Monograph: A Supplement to the NIH Guidelines for Recombinant DNA Research

6-1-30 Design Document Requirements
 
A. HVAC Documents:
HVAC Documents shall comply with the requirements listed in Appendix B “Architect-Engineer (A/E) Checklist of Services” as stated for the different phases of the particular project.  Projects phases may vary from project to project.  Typically, project phases include:  Pre-design, Schematic, Design Development, Construction Documents, and Construction Administration.
 
A.1 Pre-design Phase:
The pre-design documents shall include a brief description of all systems proposed for the project.  This is to include design criteria, methodology, redundancy, key features, and preliminary equipment sizes based on program gross square feet area.  Preliminary system diagrams shall also be included.  In addition, copy of preliminary calculations and preliminary cost estimate shall be included in this submission.
 
A.2 Schematic Design Phase:
The Schematic design documents shall include a complete description of all systems proposed for the project.  This is to include an updated design criteria, methodology, redundancy, key features, and preliminary equipment sizes based on building gross square feet area.  Updated system diagrams for all systems shall also be included.  In addition, copy of updated calculations and updated cost estimate shall be included
 
A.3 Design Development Phase:
The Design Development documents shall include an updated description of all systems proposed for the project.  This is to include an updated design criteria, methodology, redundancy, key features, and equipment sizes based room by room calculations.  Copy of all calculations shall be included in this submittal.  Updated system diagrams for all systems and utilities shall also be included.  These diagrams shall include preliminary sizing of all pipe and ductwork mains.  In addition, the following needs to be included in this submission:  copy of all heating and cooling load calculations, building energy model and lifecycle cost analysis, updated cost estimate, outline specifications, preliminary construction phasing plans, ductwork and piping floor plans with sizing for all mains in every area of the building, equipment layout, control diagrams, equipment details, room pressurization analysis, control diagrams, draft specification sections for all equipment and work including controls and commissioning, and other documents indicated in other sections of this document.
 
A.4 Construction Documents Phase:
The Construction Documents shall include: a copy of final room by room ventilation calculations, heating and cooling load calculations including all equipment sizing calculations, final energy model and life cycle analysis report, complete and fully sized riser diagrams and system diagrams for all systems and utilities, fully sized piping and ductwork floor plans, equipment lay out and details, control diagrams, final pressurization analysis, construction pashing plans, final specifications including controls and commissioning, final cost estimate, and other documents indicated in other sections of this document.
 
A.5 Construction Administration Phase:
Construction Administration typically include:  shop drawing review, provide responses to Request For Information (RFI) and drawing clarification requests, site visits and inspections, equipment startup, participation in the commissioning process, punch list development, and other activities as required by the contract.
 
B. Pressurization Analysis:
A room by room pressurization analysis shall be prepared by the A/E and submitted at the design development phase to demonstrate pressurization relationships of adjacent areas.  A schematic room layout shall be prepared and submitted with the pressurization analysis to graphically demonstrate anticipated direction of airflows between areas to be kept under positive pressure and negative pressure differentials in containment spaces.  The design documents shall include a room-by-room air balancing schedule to numerically identify supply air quantity, exhaust air quantity and offset.

C. Contractor’s Requirements:
Project construction specifications shall require the contractor to provide the following:
• Contractor shall provide startup, testing and operation verification for all equipment provided in the project.
• Contractor shall provide owner training for all equipment provided in the project.  This shall include testing, operation and maintenance.  Training shall be video taped for future training sessions.  Copy of the DVD shall be turn into the Project Officer.
• Contractor shall provide complete Operation & Maintenance (O&M) manuals for all equipment provided in the project.  This shall include copies of all equipment related shop drawings, and copy of all warranties and guarantees with the appropriate contact information.  An electronic copy, CD or DVD format, shall also be provided.  Scanned copies are not acceptable.
 
D. NIH Review of Contractor’s Submittals:
NIH reserves the right to review any and all contractors’ construction and equipment submittals.  At the NIH Project Officer’s request, copies of contractors’ submittals may be required for NIH’s review and concurrence.  The A/E shall incorporate any and all NIH review comments in the contractor’s submittal.
 
E. Renovation Projects:
Renovation projects vary in size and scope.  Complexity of renovation projects may also vary depending on the location and the type of functions in the adjacent occupied areas.  In order to minimize the impact to research in adjacent spaces, maintain the safety of staff working in adjacent spaces as well as the public in general, avoid unnecessary shutdowns, and avoid contamination of ongoing research and spaces a number of precautions shall be implemented.  The A/E shall include, in the construction documents, a proposed construction plan that is to include measures to be implemented by the contractor.  In addition, the contractor is to be required to further develop the construction plan and submit it to the Project Officer for review and approval.  Some of the construction measures include but are not limited to:
• All lab waste is to be removed and the space decontamination process must be completed prior to any demolition work.
• Dust-proof / fire-rated barriers shall be placed prior to any demolition work.  These barriers may include the use of fire-rated plastic sheeting, entry vestibules, and gasketed doors.
• Seal all wall penetrations into the construction area.
• Establish entering and exiting pathways and procedures
• Debris shall be removed in covered carts
• Exterior windows shall be sealed to reduce infiltration
• Air from areas being renovated shall not be recirculated to the building airconditioning system.
• Area being renovated shall remain under negative pressure in relation to the surrounding areas.
• Core drilling and vibration producing activities shall be deferred to unoccupied periods
• Use of sticky floor mats.
• Routinely clean up shall include HEPA vacuuming.  This may also include routinely floor mopping.  This may be required multiple times a day.
• All Laboratory space renovation shall be reviewed by DOHS and the Division of Radiation Safety (DRS)
 
 

 
This page was last updated on May 23, 2013