A06_Salient_Characteristics_3-17-2025.pdf

Salient Characteristics

Background:

The USGS Geology, Energy, and Minerals Science Center (GEMSC) Reston Microbiology Laboratory

(RML) has a need to purchase and have installed a bench-mounted Class II, Type A2 biological safety cabinet to replace the current broken Class II biological safety cabinet (nuAire Class II B2; model no:

NU-430-600; Series: 33; Serial number: 80364102102; year: 2002) currently located in 3B227. This cabinet is not currently certified, the UV light does not work, and the Type B2 requires 100% exhaust which is not compatible with the ventilation systems in the National Center. A replacement Class II, Type

A2 biological safety cabinet is necessary when culturing microorganisms, as we need to safely work with the organisms to protect the user, the environment, and samples from contamination. A Class II, Type A2 is needed as it requires 30% exhaust which is compatible with the ventilation systems in the National

Center.

Salient Characteristics:

- Class II, Type A2

- Airflow of 70% recirculating, 30% exhaust

- Width of 6 feet

- Bench-mounted Class II, Type A2 biological safety cabinet

General Design Requirements

A. Class II, Type A2 – suitable for testing and experimentation with low to moderate risk biological agents.

B. Base Stands Telescoping Stands – Support base adjustable for eight static height positions allowing the work surface height to be set between 30” or lower and 37” or higher

a. Powder coated steel square tubing construction.

b. Shall include a full width storage shelf with back panel. Back panel must include cable pass-throughs C. Cabinet shall provide biological containment protection for both operator and product through a combination of HEPA filtration and directional, controlled airflow.

D. Cabinet shall be listed with NSF International per NSF/ANSI 49-2022.

E. Dimensions

a. Overall exterior dimensions shall be a maximum of 82” w x 87” h x 31.5” d (including Base Support)

b. Interior work area dimensions shall be between 5 and 6-foot nominal width (minimum workspace 50”; maximum workspace 80”) and a minimum depth of 22” d (work surface tray at least 16”) Service Fixture (1 on right side)

c. Installed service fixture shall be quarter-turn, ball valve.

1) Valve shall be constructed of chrome-plated brass (or other based on requirements of service/utility provided).

2) Location of fixture shall be ADA-compliant.

F. Additional Specifications:

1. Ultraviolet (UV) Lamp

b. Germicidal 254 nm wavelength lamp with safety interlock. Shall be NSF listed.

c. The UV light shall be operable only when the sash is fully closed and controlled by movement and position of the sash and control panel.

2. Cord and Cable Portals

a. Shall ship with a closed cell silicone or EPDM/CR/SBR blend plug Pass-through and Service Fixtures

b. All pass-throughs and bulkheads shall be NSF/ANSI 49 approved.

3. Internal electrical outlets

a. Cabinet shall have two internal duplex electrical outlets, one mounted on each side wall.

b. Electrical outlets shall be mounted flush to the stainless-steel side walls of the biosafety cabinet’s interior.

c. Electrical outlets shall have a self-closing stainless steel splash cover with dampened operation for safe operator use. Splash covers shall fully close in 1 second or greater. Undampened, spring-loaded doors are not acceptable.

d. Electrical outlets shall be located in compliance with ADA standards.

e. 115V model receptacles are NEMA 5-15, GFCI protected.

G. Airflow

1. Face Velocity: 100 to 110 fpm per NSF/ANSI 49-2022. Average inflow velocity shall be nominally 105 fpm or better.

2. Work access opening shall be at least 8”.

3. Measured Downflow Velocity: Single point deviation shall not exceed 20% of average, be measured 4” above operational sash height, and meet manufacturers recommended velocity. Zoned downflow profiles are not acceptable.

4. DC ECM blower shall be programmed to deliver a precise airflow and automatically adjust as internal supply and exhaust filters load.

a. Auto compensating system must be capable of maintaining airflows within 2% of calibrated value. Cabinet airflow must not be impacted by line voltage variances.

b. Systems using air velocity, volume sensors or pressure transducers to control blower speed are not acceptable.

H. HEPA Filters

1. One supply and one exhaust HEPA filter. Each shall be a minimum of 99.99% efficient on all particles 0.3µm as leak tested with PAO or equivalent.

2. Motor-Blower shall automatically handle HEPA filter loading of no less than 200% from initial pressure without reducing total air delivery by more than 2%.

3. Exhaust filter shall be fully scannable from top of cabinet.

I. Controls and Display

1. Cabinet shall have crevice free, ADA compliant, solid-state controls for operation of blower, light, electrical outlets, UV Light, timer, alarm mute (with 5-minute ring-back), menu navigation and touch screen enable/disable. Muted alarms shall remain visible when silenced.

2. Alarms and Alerts

a. The cabinet shall provide both an audible signal and visual display that describes the alarm condition, provides corrective actions and utilizes a cross-sectional diagram highlighting the potentially affected areas of the biosafety cabinet.

b. Alarms and alerts shall exist for the following conditions:

1) Sash height alarm – the sash is out of operating range.

2) Sash height alert – audible sound indicating sash has moved to proper operating height.

3) Airflow alert – indicates the blower automatically made an abrupt change to maintain safe airflow.

4) System Error – indicates a failure in the communication between the microprocessor controller and the ECM blower.

5) Canopy Alarm – If canopy is indicated in Part A, canopy alarm shall indicate insufficient exhaust system airflow.

J. Noise

1. Sound level (as factory tested) shall be no more than 67 dBA, as stated and tested according to NSF/ANSI 49-2022.

K. Illumination

1. LED lighting shall provide 115 to 180 foot-candles on work surface per NSF/ANSI

49-2022. Fluorescent lighting is not acceptable.

2. LED lighting shall be externally mounted from the contaminated area and replaceable from front of the biosafety cabinet.

L. Biosafety Cabinet Qualifications

1. Cabinet shall be listed with NSF/ANSI 49-2022, shall bear the NSF Mark and shall appear in NSF’s Official Product Listings.

2. 115V, 60 Hz and 230V, 60 Hz cabinets shall meet or exceed all requirements of

UL 61010-1 and CAN/CSA C22.2 NO. 61010-1 and listed by a recognized NRTL.

M. Manufacturer’s warranty against defects in material or workmanship on its biosafety cabinets will be for 5 years from the date of installation or 6 years from date of shipment, whichever is sooner, and includes replacement of parts (excluding filters and lights/lamps) and labor.