Laboratory ventilation isn’t just about keeping the air fresh. It’s about protecting people from hazardous substances, maintaining experimental conditions, and meeting regulatory requirements that are far more demanding than standard commercial buildings.
We design and manufacture air handling units for laboratory environments across the UK — from university research labs to industrial testing facilities. The engineering challenges are unique, and getting them wrong has consequences far beyond discomfort.
Why Labs Need Specialist Ventilation
A standard office needs 6-10 air changes per hour. A laboratory typically needs 6-12 as a baseline, with specific areas requiring significantly more depending on what’s being handled. Some high-hazard environments need 15-20 air changes or more.
But air change rate alone doesn’t make a lab safe. The critical factor is airflow direction. Laboratory ventilation must maintain negative pressure relative to surrounding spaces — air flows into the lab from corridors and offices, never out. This containment principle prevents hazardous fumes, particles, or biological agents from migrating into occupied areas.
This is fundamentally different from commercial ventilation where we’re simply conditioning and circulating air. In a lab, we’re actively managing containment, and the ventilation system is part of the safety infrastructure.
Fume Cupboard Integration
Fume cupboards are the primary containment devices in most laboratories. They draw air across the work surface and exhaust it, creating a barrier between the operator and whatever they’re working with.
The laboratory ventilation system must supply enough air to feed the fume cupboards while maintaining overall room pressure relationships. When a fume cupboard sash is opened, it draws more air. The AHU and controls must respond — increasing supply air to maintain the pressure differential without creating uncomfortable draughts or wasting energy.
We design our laboratory AHU systems with variable air volume (VAV) controls that modulate supply and extract rates in real-time based on fume cupboard demand. This maintains safety while avoiding the enormous energy waste of running everything at maximum capacity permanently.
Filtration Requirements
Depending on the laboratory type, both supply and extract air may need specialist filtration.
Supply air filtration protects sensitive experiments and clean processes from external contamination. For general chemistry labs, standard filtration is usually sufficient. For biological safety labs or clean rooms, HEPA filtration becomes necessary.
Extract air filtration protects the external environment and neighbouring buildings from laboratory emissions. Carbon filters handle chemical vapours. HEPA filters capture particles and biological agents. Some applications need both.
We specify filtration based on what’s actually happening in the lab — the substances being used, the quantities, and the risk assessment. Over-specifying filtration wastes capital and increases running costs. Under-specifying puts people at risk.
Temperature and Humidity
Many laboratory processes require stable environmental conditions. Analytical equipment, biological cultures, and chemical reactions can all be sensitive to temperature and humidity variation.
Maintaining tight conditions in a laboratory is harder than in a standard building because the high air change rates and variable fume cupboard loads constantly disturb the environment. The AHU needs sufficient heating and cooling capacity to compensate, with responsive controls that keep conditions stable despite fluctuating demand.
We’ve designed systems where temperature stability of ±0.5°C was required in specific lab areas — achievable, but only with careful coil sizing, sensor placement, and control strategy.
Energy Considerations
Laboratories are energy-intensive. The combination of high air change rates, no recirculation (100% fresh air is common in labs handling hazardous materials), and tight environmental control creates significant heating and cooling loads.
Energy recovery is critical for managing these costs. However, standard heat recovery methods need careful consideration in laboratory applications. Thermal wheels are generally unsuitable because of cross-contamination risk between supply and extract streams. Run-around coils or plate heat exchangers with appropriate separation are safer options.
We always balance energy efficiency against safety requirements. No energy saving justifies compromising containment or exposing occupants to hazardous substances.
Redundancy and Resilience
Laboratory ventilation often needs to run continuously — even outside occupied hours — to maintain containment and purge residual hazards. Unplanned shutdowns can compromise safety and halt research.
We design redundancy into critical laboratory systems: standby fans, automatic changeover controls, and alarm systems that alert facilities teams to any ventilation failure. The level of redundancy depends on the hazard classification and operational requirements.
Regular maintenance is equally critical. Filter changes, fan inspections, and control calibration must happen on schedule — a laboratory AHU that’s neglected isn’t just inefficient, it’s dangerous.
Our Approach
i-Flow Technologies designs and manufactures bespoke air handling units for laboratory applications. We work with architects, M&E consultants, and end users to develop ventilation solutions that meet safety requirements, regulatory standards, and operational needs.
Whether you’re fitting out a new laboratory, upgrading existing ventilation, or need specialist advice on containment ventilation, contact us to discuss your project.
