COMPARATIVE ANALYSIS

RECIRCULATING FUME CUPBOARDS (NON-DUCTED)

Pros

• Lower Installation Costs: Non-ducted systems have a lower initial installation cost. The total CAPEX, including delivery, installation, and commissioning, is £6,506.00, which is substantially less than ducted systems.
• Energy Efficiency: These systems are more energy-efficient, with an annual electricity cost of approximately £100.00 at 0.5 m/s airflow.
• Flexibility and Mobility: Non-ducted fume cupboards can be easily moved and reinstalled, offering greater flexibility for laboratories that may undergo reconfiguration or relocation.
• Environmental Sustainability: Non-ducted systems are more environmentally friendly as they recirculate air within the laboratory after filtration, reducing the need for external ducting and associated energy losses. They also minimise the release of contaminants into the external environment.

Cons

• Higher Maintenance Costs: Over a five-year period, the operating and maintenance costs for non-ducted systems are higher. This includes the recommended annual replacement of activated carbon filters.
• Potential for Filter Saturation: Non-ducted systems rely on filters to remove hazardous substances. If not properly maintained, there is a risk of filter saturation, which can compromise the system’s efficiency and safety.
• Limited Suitability for High-Hazard Applications: Non-ducted systems may not be suitable for all types of hazardous materials, especially those that produce highly toxic or corrosive fumes.

 

DUCTED FUME CUPBOARDS

Pros

• Efficient Removal of Hazardous Gases: Ducted fume cupboards are highly effective at expelling hazardous gases and vapours outside the building, ensuring optimal air quality within the laboratory.
• Lower Maintenance Costs: With fewer components to service, ducted systems generally have lower maintenance requirements.
• Consistency in Performance: These systems provide consistent airflow and containment, which is essential for high-volume and high-hazard applications.

Cons

• High Initial Installation Costs: The installation of a ducted fume cupboard is significantly more expensive. The total capital expenditure (CAPEX) for a ducted system, including delivery, installation, and ducting (Fan, inverter + duct (2no. Straight + 2no. Bend)), reaches £11,251.00.
• Higher Energy Consumption: Ducted systems consume more electricity. For instance, at 0.5 m/s airflow, the electricity cost is in excess of £500.00, annually.
• Lack of Flexibility: Once installed, ducted systems are not easily relocated, limiting their flexibility within dynamic laboratory environments.

COST COMPARISON

The initial capital expenditure (CAPEX) for a non-ducted system like the CT1100 is significantly lower compared to the ducted DFC1200. However, over five years, the operational expenditure (OPEX) for the non-ducted system is higher.

The overall cost over five years for the non-ducted system is still 28% less than the cost for the ducted system. This cost efficiency, combined with the environmental benefits, makes non-ducted systems an attractive option for many laboratories.

 

	Recirculating Fume Cupboard		Ducted Fume Cupboard
Equipment + Installation	CT1100 1100mm x 1285mm x 700mm (WDH)	£5,911.00	DFC1200 1200mm x 700mm x 1026mm (WDH)	£3,801.00
	Delivery + Installation + Commissioning	£595.00	Delivery + Installation + Ducting*	£7,450.00
	CAP EX TOTAL	£6,506.00	CAP EX TOTAL	£11,251.00
		£4,745.00	73%
Operating + Maintenance	Electricity Use @ 0.5m/s**	£105.78	Electricity Use @ 0.5m/s**	£509.18
		£403.40	79%
	Service + Filters***	£1,044.00	Service	£370.00
		(£674.00)	-65%
	OP EX TOTAL****	£5,748.90	OP EX TOTAL****	£4,395.90
Total	RECIRC.  TOTAL	£12,254.90	DUCTED TOTAL	£15,646.90
	TOTAL SAVING RECIRC. vs DUCTED	£3,392.00	28%

* Duct run cost based upon; Fan, inverter + duct (2no. Straight + 2no. Bend)

** Energy usage; 8 hrs/365 days @ 22.5p/kWh

*** MonSci recommendation to replace activated carbon filters annually (2no. Filters in CT1100)

****Operating + Maintenance over a 5-year period

Accurate July 2024

ENVIRONMENTAL AND SUSTAINABLE BENEFITS OF NON-DUCTED SYSTEMS

One of the most compelling advantages of non-ducted fume cupboards is their environmental sustainability. By recirculating filtered air back into the laboratory, these systems reduce the energy required for heating or cooling replacement air, which is particularly beneficial in large facilities. This reduction in energy consumption directly translates to lower greenhouse gas emissions, contributing to a more sustainable laboratory operation.

Furthermore, the reduced need for extensive ducting infrastructure not only cuts down on material usage but also minimises the environmental impact associated with production and installation. The flexibility and mobility of non-ducted systems also mean that laboratories can adapt to changing needs without the environmental cost of installing new ductwork.

SUMMARY

Choosing between ducted and non-ducted fume cupboards depends on a variety of factors, including budget, specific laboratory requirements, and sustainability goals. Ducted systems offer reliability and lower maintenance costs, making them ideal for high-hazard applications. In contrast, non-ducted systems provide significant installation cost savings, energy efficiency, and environmental benefits, making them a strong contender for many laboratories, especially those focused on sustainability.