This year’s S-Lab event, held at Nottingham University, was a meeting of architects, construction and engineering companies, equipment suppliers and, most importantly, laboratory operators. The focus was good practice in lab design, management and operation for new and refurbished labs.
With seven streams of presentations running simultaneously, and lab tours of two new facilities on the Nottingham University Campus, it is impossible to cover all the talks at this event.
This summary, therefore, reports on those that discussed improving lab layouts and reducing energy use – areas of relevance to both lab and cleanroom operators.
In previous years the focus was on best use of lab resources due to energy cuts, and the academic and commercial world slowly had to embrace the once-inconceivable idea of sharing labs with different departments.
This year the trend was all about providing larger, more pleasant and inviting, flexible, open plan teaching spaces on a par with commercial labs.
This is being achieved with better use of natural light, new grid-based layouts, and better sited M&E services delivered to each bench station via overhead booms that are easy to access, reconfigure and maintain.
Many of the case studies presented highlighted the need for labs to provide multi-use facilities with good sight lines for better teaching as the spaces have got larger to accommodate growing student numbers. Typical of many new teaching labs is that for the University of East Anglia, which is at the feasibility stage and will provide 50 fume cupboards in one large teaching space.
The presentation by Phil Hadfield, Romero, UK, and John Hennessey of Premier Laboratory Systems, looked at how enhanced laboratory design can assist with today’s modern scientific teaching demands.
Open plan layouts make student assessment easier and safer, while laboratory servicing is planned on a grid system to enable facilities to be more adaptable for multi functional use.
For example, they looked at the concept for the AstraZeneca building now under construction in Cambridge, which comprises large open labs with electrical and piped services in overhead service booms, accompanied by modular relocatable lab benching – resulting in minimal obstructions for the user and enabling more collaborative research.
The University of Nottingham’s new Chemistry Facility Laboratory is also serviced on a grid system with quick-release service fittings.
Services with power outlets and data outlets are clustered, and there are quick-release gas media outlets, extract connection spigot fume cupboards.
HVAC and energy use
Heating, cooling and ventilation of the labs, as well as air supply and extract to fume cupboards and isolators accounts for a large amount of any facility's energy use.
For much of the time these buildings are empty but still using energy. Therefore use of variable-air-volume (VAV) fume hoods, more efficient chillers and chill beams has become more important.
Passive ventilation, that makes use of natural forces, such as wind and thermal buoyancy, are increasingly being incorporated where possible.
Kings College London, for example, has constructed a passive ventilation system that cools 15 ultra-low temperature freezers safely. (This is clearly something more suitable for those in cooler climatic regions.)
Kings has also made improvements by retrofitting VAV to heavily-used fume cupboards and flow reductions through evidenced containment.
Drying cabinet replacement with more economical models is another option.
Dynamic control of ventilation
Most labs use a massive flow of air on the basis of diluting contaminants for safe operation, but those contaminant incidents are few and far between – possibly only 10% of the time or less.
Thus demand driven and dynamic control of ventilation is being looked at more and more and will allow vastly reduce air change rates.
Gordon P. Sharp, of AirCuity, which offers demand-based control (DBC) solutions, said that DBC has been tried and successfully employed in labs around the world over the past few years.
It involves reducing lab airflow when the lab air is ‘clean’ and increasing lab flow when pollutants are sensed.
Most fixed Air Changes per Hour values are being dropped, said Sharp, and he noted that the new 2011 ASHRAE Handbook, Lab chapter 16 recommends active/demand based control: ‘Reducing ventilation requirements in laboratories and vivariums based on real-time sensing of contaminants in the room environment offers opportunities for energy conservation.’
It continues, ‘This approach can potentially reduce lab air change rates down safely to as low as two air changes per hour when the lab air is ‘clean’...'
Using DBC, lab HVAC energy can be cut by 40–70%, he said, and capital costs can also be reduced as smaller HVAC systems are required. Other commercial systems are being developed by a joint venture with Halton Products.
Fume cupboard design
Much discussion focused on the latest fume cupboard design. Today fume cupboards are designed to provide a larger internal working space and some have height adjustable frames.
They can have toughened glass rear and sides to offer greater visibility. Many of the new designs ensure that containment is unaffected when an operator stands or moves in front of the fume cupboard or when bulky equipment is placed within the cupboard.
Less air movement also means greater user comfort and the lower velocity makes it easy to handle powders or carry out accurate weighing of substances. Fume extraction is a major factor in energy consumption and getting the ventilation and chimney stack heights right is a complex process.
In this respect, Brad Cochran, CPP, discussed the use of dispersion modelling to help design safe yet more energy efficient lab extract systems.
It was fascinating to learn how engineers and universities are responding to the challenges of reducing energy use and making science teaching a much more pleasant and sustainable activity than it has been in the past.
For details of this and the next S-Lab event being held in York in early summer 2017 visit http://www.effectivelab.org.uk
