Ventilation system made of copper

 Ventilation ducts and fittings made of copper sheet

A ventilation system made of copper is a guarantee of aesthetics, durability and low cost of operation. Such an installation, apart from its unique style and colour, is also very durable. It does not undergo corrosion; moreover, it is resistant to changes in atmospheric conditions and air pressure in the installation.

Copper - main features

The characteristics of copper perfVentilation air duct made of copper sheetectly match the needs of users of ventilation systems. Copper is an excellent conductor of heat and electricity. Additionally, in a natural way, it prevents the growth of bacteria.

Copper, thanks to its properties, is very durable and plastic. In contact with moist air, a layer of patina is formed. Copper reacts with air containing water vapour, is susceptible to fresh well-oxygenated water, but does not react in contact with seawater.

The following have a strong effect on copper:

  • chlorine compounds,
  • acids,
  • chlorinated lime,
  • and mortar.

Copper dissolves in nitric acid. Copper has a high resistance to temperature and pressure fluctuations. Additionally, it is non-combustible.

Thanks to its biostatic properties, copper inhibits the growth of bacteria. Research approved by the EPA (Environmental Protection Agency of the United States) proves that copper destroys harmful bacteria, germs, microbes, pathogens, moulds, fungi and viruses that come in contact with the surface of copper ducts. In addition, a copper ventilation installation is much safer than a steel installation that must be regularly cleaned using ozone and chemical biocides.

Bactericidal properties of copper

The bactericidal function of a material, what do we mean by this? The bactericidal function of material means the ability to inhibit the growth of a wide range of micro-organisms such as bacteria, moulds, fungi, viruses and yeasts on a given surface. When exposed to bacteria on copper surfaces the material exhibits germicidal properties, this is confirmed by Environmental Protection Agency (EPA) studies.

In the table below we can see the different types of bacteria applied in a specific way to copper and the time of their inactivation. 

Through these observations, the following conclusions can be drawn: higher temperature and higher relative humidity increase the effectiveness of contact killing. Treatments that reduce the corrosion rate, e.g. the use of corrosion inhibitors or a thick layer of copper oxide, reduce the antimicrobial effectiveness of copper surfaces. 

Tabel 1. Contact killing of microbes by copper surfaces

Species Application method Killing time, RTa
Salmonella enterica Wet, 4.5 × 106 CFUb 4 h
Campylobacter jejuni Wet, 4.5 × 106 CFUb 8 h
Escherichia coli O157 Wet, (3-4) × 107 CFUc 65 min
Escherichia coli O157 Wet, 2.7 × 107 CFUc 75 min
MRSAd (NCTC10442) Wet, (1-1.9) × 107 CFUc 45 min
EMRSA-1e (NCTC11939) Wet, (1-1.9) × 107 CFUc 60 min
EMRSA-16e (NCTC13143) Wet, (1-1.9) × 105 CFUc 90 min
Listeria monocytogenes Scott A Wet, 107 CFUc 60 min
Mycobacterium tuberculosis Wet, 2.5 × 107 CFUf 5 to 15 daysg
Candida albicans Wet, >105 CFUf 60 min
Klebsiella pneumoniae Wet, >107 CFUf 60 min
Pseudomonas aeruginosa Wet, >107 CFUf 180 min
Acinetobacter baumannii Wet, >107 CFUf 180 min
MRSA Wet, >107 CFUf 180 min
Influenza A virus (H1N1) Wet, 5 × 105 virusesh 6 h, 4-log decrease
C. difficile (ATCC 9689) vegetative cells and spores Wet, 2.2 × 105 CFUc 24-48 h
C. difficile NCTC11204/R20291 vegetative cells Wet, (1-5) × 106 CFUi 30 min
C. difficile dormant spores Wet, 8 × 106 CFUi Unaffected in 3 h
C. difficile germinating spores Wet, 8 × 106 CFUi 3 h, 3-log decrease
Pseudomonas aeruginosa PAO1 Wet, 2.2 × 107 CFUj 120 min
MRSA NCTC 10442 Wet, 2 × 107 CFU 75 min, 7 log decrease
Escherichia coli W3110 Dry, 109 CFUi 1 min
Acinetobacter johnsonii DSM6963 Dry, 109 CFUk A few minutes
Pantoea stewartii DSM30176 Dry, 109 CFUi 1 min
Pseudomonas oleovorans DSM 1045 Dry, 109 CFUk 1 min
Staphylococcus warnerii DSM20316 Dry, 109 CFUk A few minutes
Brachybacterium conglomeratum DSM 10241 Dry, 109 CFUk A few minutes
Aspergillus flavus Wet, (2-300) × 105 sporesc 120 h
Aspergillus fumigatus Wet, (2-300) × 105 sporesc >120 h
Aspergillus niger Wet, (2-300) × 105 sporesc > 576 h
Fusarium culmonium Wet, (2-300) × 105 sporesc 24 h
Fusarium oxysporum Wet, (2-300) × 105 sporesc 24 h
Fusarium solani Wet, (2-300) × 105 sporesc 24 h
Penicillium crysogenum Wet, (2-300) × 105 sporesc 24 h
Candida albicans Wet, (2-300) × 105 sporesc 24 h
Enterococcus hirae ATCC 9790 Wet, 107 CFUc 90 min
Different Enterococcus spp. Wet, 106 CFUf 60 min
Candida albicans Dry, 106 CFUk 5 min
Saccharomyces cerevisiae Dry, 106 CFUk 30 s


RT, room temperature; only the values for the most efficient alloy are reported.
Inoculation with 1.5 ml of culture (4.5 × 106 CFU), kept under humid conditions.
Inoculation with a 20-μl drop of culture.
Methicillin-resistant Staphylococcus aureus.
Epidemic methicillin-resistant Staphylococcus aureus.
Twenty microliters of culture spread on coupons.
Time before strain became culture positive in Bactec 12B growth medium after exposure to copper.
Inoculation with 20 μl of virion suspension.
One hundred microliters of dilute culture.
Twenty-five microliters of culture spread on coupons with a glass spreader.
Thin film applied with a cotton swab.

The mechanism for killing bacteria is shown in the figure below.

Mechanism for killing bacteria

FIG. 1. Cartoon of the tentative events in contact killing. (A) Copper dissolves from the copper surface and causes cell damage. (B) The cell membrane ruptures because of copper and other stress phenomena, leading to loss of membrane potential and cytoplasmic content. (C) Copper ions induce the generation of reactive oxygen species, which cause further cell damage. (D) Genomic and plasmid DNA becomes degraded.

The bactericidal properties of copper are of continuous interest to scientists. Research and analyses are conducted on various applications of this material, e.g. in hospitals, public buildings, public transport. Everywhere where there is a risk of bacterial concentrations.

Additionally, copper conducts heat very well, thanks to which this material is ideal for installation for heat exchangers. Copper installations are a good choice for places exposed to seawater as they do not react with saline.

Copper ductwork

Ventilation ducts and fittings also can be made of copper - thus, they take the natural antibacterial properties of the material. Copper ductwork is made in the same technology as traditional spirally wound galvanized SPR-C ducts. Available diameters range from 100 to 500 mm, including all intermediate dimensions produced from a material of a thickness of 0.5Ventilation fabricated elbow made of  copper mm.

Check technical data for spiral ducting

Segment fittings that are connected to pipes by means of male couplings can also be made in a system with EPDM seals, providing an increased airtightness class. Copper bends, T-pieces, reducers, and ventilation nozzles are made in segments of dimensions compatible with galvanized fittings.

Copper roof cowls match perfectly roofs made of this material; they both change colour during the oxidation process. Thanks to this, roof edges will form a coherent whole.

In addition to the functional properties of copper ventilation elements, the characteristic colour of copper is also worth noting. Thanks to it, copper ducting adds uniqueness to the design of modern lofts and stylish retro interiors.

1. Metallic Copper as an Antimicrobial Surface Gregor Grass, Christopher Rensing, Marc Solioz Appl Environ Microbiol. 2011 Mar; 77(5): 1541–1547. Published online 2010 Dec 30. 

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