Ventilation Concerns When Renovating the Occupied Lab

Lab Manager speaks to Luke Savage, director of ventilation technologies with Labconco Corp. of Kansas City, MO, about what needs to be considered when planning to renovate an occupied lab facility.

Q: What needs to be taken into consideration when deciding to renovate an occupied lab, versus clearing out a research/work team from the lab in order to complete the renovations?
A: One thing to consider in this situation is the type of mechanical exhaust air system supporting the laboratory ventilation containment equipment. If a fume hood, ducted enclosure, or ducted biological safety cabinet are on a shared mechanical system and slotted for replacement as part of the renovation, careful coordination with the mechanical design, construction, and environmental health and safety teams will be required.

Some variable air volume (VAV) type mechanical systems are equipped with sophisticated controls, enabling a clean lock-out of hoods without influencing other equipment. However, if the building’s exhaust airflow is of the constant air volume (CAV) variety, it is impossible to remove these containment devices without influencing the certified airflow moving through other containment devices on the same mechanical system. This is a significant safety concern. As each lab segment is to be renovated, all ventilation containment devices should be locked out of service. The segment of the mechanical system that is part of the renovation should be isolated. The mechanical system should be rebalanced, and the facility chemical hygiene officer must confirm safe operation of other containment equipment, as well as the integrity of directional airflows both in and out of labs, before these devices can be put back into operation providing user safety. The cost of this required iterative process to maintain safety may be a deterrent to occupied lab renovation.

Q: What are some strategies used when determining the budget and timeline for an occupied lab renovation? What happens if a project exceeds those estimates?
A: With any lab renovation, we seek to maximize the efficiency of the space; often that means adding ventilation safety equipment. This can be invasive, expensive, and a major hurdle in occupied labs. More and more, lab planners are seeking ventilation containment equipment which eliminates the need to modify the building’s mechanical ventilation system.

Chemical filtration technology has advanced by leaps and bounds in the last decade. Consequently, ductless fume hood and carbon filtered enclosure options are far more prevalent for chemical applications. The technology is still limited, so lab managers need to do their homework up front. Learn what applications in their lab are candidates for this type of technology by working directly with ductless fume hood equipment representatives. By answering a few simple questions about what chemicals are in use, their volumes, and frequency of use, most manufacturers can deliver detailed chemical assessments including appropriateness of the application for the technology, as well as anticipated filter life. By not involving the mechanical system in your redesign, you can slash your budget and your timeline.

Another really common situation we find these days is the addition of a volatile chemical to a typical biological application. In the past, this would mean that your lab was facing the addition of a B-type cabinet, and mandatory dedicated exhaust ducting and equivalent addition to supply air. This would cause significant cost and disruption to an occupied lab.

In recent years though biological containment device manufactures have developed the type C1 biological safety cabinet. With a portion of the interior work area dedicated to working with chemicals in addition to biological hazards, this new technology can be added to most mechanical ventilation systems without much headache, or as a replacement to a ducted A-type cabinet with only rebalancing needed, because it needs very similar airflow to an equivalently sized A2 cabinet. By minimizing the mechanical system adjustments in your renovation, your lab will be operational sooner and for less money.

Q: Is there anything else that the Lab Manager audience should know about occupied lab renovations?

A: Often with a laboratory renovation, we find an expectation of reduced operating cost in the form of lower utility bills. This is definitely achievable with the use of modern fume hoods. If your laboratory is interested in pursuing this objective as part of your renovation, your environmental health and safety team should ensure they have a well-developed chemical hygiene plan. Part of this plan requires defining the minimum airflows and fume hood face velocities required to achieve safe containment, as well as defining the pass/fail criteria for evaluating fume hood containment. This might seem daunting. However, most laboratory planners are more than willing to assist in this process, and then to apply equipment that meets the unique performance requirements of your laboratory. The energy savings of moving to high performance fume hoods can be staggering, sometimes yielding a return on capital investment in just a few short years. Lab managers should keep in mind when comparing efficient fume hoods that the metric of fume hood operating cost is the volumetric rate (typically measured in CFM), not the face velocity (typically measured in fpm); low face velocity and high volumetric rates will not save you anything.