CDS: Division 11

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Division 11 Equipment

Division 11-1 Vending Equipment

A.	Program And Planning Guidelines For Vending

1.	University of California at Berkeley has a high demand for vending in its facilities. However, vending is typically not considered until after the users have occupied the building. Obviously, after the fact, space availability and code compliance become major obstacles. ASUC provides this service for the campus and encourages the review and determination of the need for vending services in the program and planning stage of all University of California at Berkeley facilities.

2.	Issues to consider:

a.	Functions: Is there a lounge for social or functional purposes where vending services would facilitate same?

b.	Use: Will students or public who may have special need for vending services be using the facility? Will faculty, students, staff or public use the facility after 5:00 p.m.? NOTE: After hours, service availability is a major concern for both convenience and safety reasons.

c.	Activity Level: Is there medium to high traffic in the facility?

d.	Location: Is facility immediately bordering existing, or adequate services?

Division 11-2 Fume Hoods (See ACGIH Ventilation Handbook and 8CCR5154.2)

1.	Fume hoods shall be located in areas of minimum air turbulence and away from doors and windows, and in a manner that will not impede egress.

3.	Each hood must have a visual indicator so that operators can determine at all times if hood is functioning (e.g., magnahelic gauge).

4.	Shutoff valves for services, including gas, air, vacuum and electricity, shall be outside of the hood enclosure in a location where they will be readily accessible in the event of fire in the hood. The location of such shutoffs shall be legibly lettered in a related location on the exterior of the hood.

5.	Initial testing results for fume hood face velocities must be forwarded to Environment, Health and Safety (EH&S). For vertical sash hoods, sash height where readings were taken must be indicated both on the hood and in the testing results.

6.	Selection of equipment and associated exhaust systems for perchloric acid hoods and biological safety cabinets shall be carefully reviewed prior to final planning stages with Capital Projects (CP) and the office of Environment, Health and Safety (EH&S). Radio-isotope hoods must be reviewed by CP and the Office of Radiation Safety (ORS).

a.	Perchloric Acid Hoods:

i.	If perchloric acid is heated above ambient temperature and vapors are not trapped or scrubbed before entering the laboratory hood or its exhaust system, a separate hood, designed for use with perchloric acid and labeled For Perchloric Acid Use Only, shal be provided.

ii.	Perchloric acid hoods and exhaust duct work shall be constructed of materials that are acid resistant, non-reactive and impervious to perchloric acid.

iii.	The exhaust fan shall be acid resistant and non-sparking. The exhaust fan motor shall not be located within the duct work. Drive belts shall be non-conductive and shall not be located within the duct work.

iv.	Ductwork for perchloric acid hoods and exhaust systems shall take the shortest and straightest path to the outside of the building and shall not be manifolded with other exhaust systems. Horizontal runs shall be as short as possible, with no sharp turns or bends. The duct work shall provide a positive drainage slope back into the hood. Duct work shall consist of sealed sections. Flexible connectors shall not be used. Ductwork serving perchloric acid hoods shall be labeled ³Perchloric Acid Hood Duct.²

v.	Sealants, gaskets and lubricants used with perchloric acid hoods, duct work and exhaust systems shall be acid resistant and non-reactive with perchloric acid.

vi.	A water spray system shall be provided for washing down the hood interior behind the baffle and the entire exhaust system. The hood work surface shall be watertight with a minimum depression of 1/2" at the front and sides. An integral trough shall be provided at the rear of the hood to collect wash down water.

vii.	The hood baffle shall be removable for inspection and cleaning.

viii.	Note: If remodel work is done on existing perchloric acid hoods, duct work or exhaust fans, workers must be alerted. Contact EH&S for special safety procedures to avoid explosions.

7.	To reduce energy use of hood systems, consider the use of variable volume hood controls. Do a life cycle cost analysis of variable volume and constant volume systems and select optimal system. Any proposed use of variable volume hoods must be reviewed and approved by EH&S.

8.	See Division 15 for fume hood ductwork requirements.

9.	Rooftop exhaust stacks for chemical fume hoods must extend at least seven feet above the rooftop and discharge vertically upward. Where this is not feasible, alternate designs must be approved by EH&S.

Division 11-3 Biological Safety Cabinets

1.	Biological Safety Cabinets are not chemical fume hoods, they are a vented cabinet that serves as a primary containment device for operations involving biohazardous agents or materials. Biological safety cabinets must notbe used as the only exhaust from a laboratory.

a.	Class I Biological Safety Cabinets: A class I cabinet resembles a chemical fume hood except that the exhaust air is filtered. Filter selection (HEPA, charcoal, etc.) is dependent upon the type of research being conducted. Sizing of the exhaust system must take into account the flow resistance of the chosen filtration system.

b.	Glove Boxes (Class III Biological Safety Cabinets)‹See ACGIH Ventilation Handbook

i.	The glove box shall be maintained under negative pressure (0.25 to 0.50 in w.g.) relative to the laboratory. Sizing of the exhaust system must take into account the flow resistance of the chosen filtration system.

ii.	Exhaust from the glove box shall be cleaned in two or more stages. First, a pre-filter to remove the major load of coarse particulate matter followed by a HEPA filter with a minimum efficiency of 99.97% for 0.3 um test aerosol particles. When highly toxic volatile chemicals are to be used, an activated charcoal adsorber stage should be added to the air cleaning train.

iii.	The atmosphere inside the box may be maintained sterile and dust-free by use of a constant air in-leakage through a HEPA filter. Air locks shall be included in the design for passing items into and out of the glove box.

Class II Biological Safety Cabinets - See National Sanitation Foundation Standard 49 and 8CCR5154.2 There are fourbasic types of biological safety cabinets: Class II-Type A, -Type B1 -Type B2 (or total exhaust) and -Type B3. These types differ in the proportion of air re-circulated into the work area; the velocities of the airflows into the work opening and downward to the work surface; the manner of discharge of exhaust air; and the pressure in contaminated air plenums relative to the room.

i.	Biological safety cabinet should be located out of the traffic pattern and away from doors, preferably at the dead-end of the laboratory. The cabinet should be placed so that there is a minimum clearance of 3" on each side of the cabinet and at least 1-1/2" in back. Sufficient clearance shall be maintained above the cabinet to allow testing, a minimum of 12¹ above to any structure. The discharge from nearby supply air registers should b directed away from the cabinets. The electrical outlet for the cabinet should be accessible for service and electrical safety testing without moving the cabinet.

ii.	Biological safety cabinets installed as part of building or renovation project must be tested and certified in place as meeting National Sanitation Foundation Standard 49 prior to completion of the project. Records of certification must be forwarded to Environment, Health and Safety (EH&S).

iii.	Class II, Type A cabinets are designed to return air to the laboratory, and do not generally require external venting. If a cabinet is vented into a common exhaust system, a canopy connection is recommended (see Recommendations for Installation from NSF Manual.)

iv.	Class II, Type B cabinets require an external exhaust blower and should be connected directly to an exhaust system that discharges to the outdoors. The venting system must include a leak-tight duct, a damper in the duct near the cabinet to permit flow adjustment and decontamination, and an external exhaust blower as the final system component (see Recommendations for Installation from NSF Manual).

A.	The exhaust blower must be sized to deliver the required exhaust airflow (as specified by the cabinet manufacturer), considering pressure losses in the duct, and allowing at least 2" wg for a dirty HEPA filter. If a charcoal filter is used downstream of the HEPA filter, an additional 1" wg or the manufacturer's recommended resistance should be provided.

B.	An audible and visible alarm must be provided at the cabinet to indicate loss of exhaust flow in accordance with 8CCR5154.2. This can be a differential pressur switch across the exhaust filter, sail switch at the blower discharge, or flow measuring station in the exhaust duct.

C.	It is recommended that each Type B cabinet have its own exhaust system and not be ganged with other Biological Safety Cabinets or chemical fume hoods. If a Type B cabinet contains an internal blower which provides or contributes to exhaust flow and feeds into a system with an external blower, the cabinet and external blowers must be interlocked.

Division 11-4 Solvent Storage Cabinets

1.	Provide capability to exhaust solvent storage cabinets.

2.	Doors to solvent storage cabinets must be self-closing with a latch, but are not required to be self-latching in accordance with codes.

Division 11-5 Waste Handling Equipment

Trash areas to be located in exterior service area of building, preferably equipped with a loading dock. Trash bins to be standard 2 cubic yard rear loading Garland type containers, minimum one per 15,000 sq. ft. building space. Ease of access msut be provided to facilitate maneuverability of two axle, 20 cubic yard rear loading refuse vehicle.

Compactor use must be approved by owner prior to specifying.

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