HVAC and Fume Hoods

Assess Minimum Ventilation Requirements

 

Multi-stakeholder ventilation team: The ventilation requirements shall be determined and documented by a team including each of the following professionals: A/E Team, Laboratory Consultants*, User Representative, Owner Facilities Group, Owner Environmental Health & Safety, Commissioning Authority*, Construction Manager* (*If these have not been appointed, an individual who independently and conscientiously represents these interests.)

 

The team shall, at a minimum, do the following:

 

1.  Determine the necessary fresh air ventilation rate and number of fume hoods and other exhaust devices based on applicable codes and the planned use of the laboratory over the next 5 years.

 

2.  Consider different types of fume hoods and exhaust alternatives to fume hoods, such as instrument exhausts and ventilated storage cabinets with very low flow ventilation and good ergonomic accessibility.

 

3. Develop a fume hood sash management plan including:

  • Informational placards for hoods;
  • Awareness and Use Training.
  • The Sash Management Plan should be incorporated in the Chemical Hygiene Plan for the laboratory.

The process and findings should be documented. See the Labs21 Environmental Performance Criteria Version 3.0 for more details.

 

EA EPC Prerequisite 1: Assess Minimum Ventilation Requirements

 

Laboratory Ventilation

 

Ensure that minimum requirements for Indoor Air Quality (IAQ) and safety are met. Meet the minimum requirements of ANSI/AIHA Z9.5 (latest version).

 

Mandatory - UC Policy

EQ EPC Prerequisite 1: Laboratory Ventilation

 

Protection and Notification Systems

 

Ensure health, safety, and awareness of employees.

 

Design all alarm systems in the laboratory to be inherently self-identifying and failsafe. Alarms systems shall include but are not limited to: fume hood alarms, ventilation alarm, exterior door/window alarms.

 

Occupant notification device shall be incorporated into chemical fume hoods, when variable air volume (VAV) systems are installed, to measure the change of tempered exhaust volumes when the fume hood sash is raised or lowered.

 

Provide a notification system to laboratory occupants for all doors leading directly from pressure-controlled laboratory spaces to the outside.

 

Fume hoods and other equipment affected by cross-drafts must not be placed adjacent to exit doors except emergency-only exits, unless adequate precautious are in place to prevent fume hood operation with door open.  “Adjacent to exit door” means 6 feet or less.

 

Mandatory - UC Policy

EQ EPC Prerequisite 2: Protection and Notification Systems

 

Laboratory Air Flow Analysis

 

Ensure health and safety of laboratory occupants. Optimize indoor airflow based on results of computational fluid dynamics (CFD) or physical modeling.

 

Recommended

EQ EPC Credit 1: Laboratory Air Flow Analysis

 

Containment Device Commissioning

 

Ensure health and safety of laboratory occupants.

 

Conduct fume hood commissioning that includes ASHRAE-110 Method of Testing Performance of Laboratory Fume Hoods (latest version) As Installed. The following performance tests specified in the standard shall be witnessed:

  • Airflow visualization
  • Cross drafts velocity
  • Exhaust flow measurements; at different sash configurations for VAV hoods
  • Face velocity; at different sash configurations for VAV hoods
  • VAV Response and Stability
  • Hood static pressure measurement
  • Tracer gas containment tests. The hood performance rating for the Tracer Gas Test procedure shall be at least 4.0 AI 0.1 as specified in ANSI Z9.5.

Comply with the Scientific Equipment and Furniture Association (SEFA) 1.2 “As Installed” recommended practices for chemical fume hoods.

 

Biosafety cabinets must meet or exceed the requirements of, and be currently listed by, the NSF International Standard 49 (latest edition, current edition is 49-04a) as meeting the design and construction requirements of the standard. Cabinets must also be field tested and certified “as installed” to meet the performance requirements of the standard. Only biosafety cabinets that depend on exhaust to the outside to maintain performance need to be recertified under conditions of reduced air supply. Most biosafety cabinets do not depend on exhaust to the outside to maintain performance and only need to be certified under normal conditions.

 

For exhaust devices that do not have standardized test procedures (e.g. ventilated storage cabinets, snorkels, instrument exhausts), verify performance with smoke test or other appropriate method as described in the Labs21 Best Practice Guide on Exhaust Devices Commissioning.

 

If air supply and exhaust are reduced when the laboratory is unoccupied, all devices that exhaust air must meet containment requirements with normal and reduced air supply. This requirement applies to any case that varies the air supplied through a device without varying any operating parameters of the device (e.g. sash height, baffle position).

 

Recommended

EQ EPC Credit 2: Containment Device Commissioning