Screen Shot 2557-11-10 at 5.04.13 PM

What is Biofilm?

A biofilm can be broadly defined as a collection of micro-organisms that have made contact with a surface and between each other secrete sticky polymeric substances that act as a protective shell and source for capturing nutrients like dust that help the biofilm to grow.

Micro-organisms commonly go through stages of attachment, growth and dispersal to develop complex structures and relationships that have been described as “slime cities”. In fact the biofilm “lifestyle” may well be the most common mode of existence in the natural environment.

Biofilms form on many types of surfaces but one of the most common is where water is in contact with a solid surface as the two requirements for biofilm to grow are the presence of micro-organisms and moisture.

These conditions exist in an enormous number of situations around the world and include air conditioning heat exchangers, cooling towers and commercial water circuits – such as those found in mines and paper mills.

What is Biofilm?

aerisenv-15--eeshe  aerisenv-15--peeli

Slippery coating on a rock Dental plaque

“Biofilms are the prominent life form of microorganisms and account for over 60% of human infections and virtually all, chronic, recurrent and implanted device associated infections.”

Center for Disease Control & Prevention, 2000

Biofilm formation, structure and characteristics

Stage One: Attachment
Bacteria float around and begin to attach and communicate with one another. They start releasing a sticky substance.
Stage Two: Colonisation
More and more passing bacteria attach to the biofilm.



Stage Three: Growth
The biofilm grows quickly.
Stage Four: Detachment (Final Biofilm)
At full growth, pieces begin to break off and new pieces grow back quickly.

Why biofilm is so hard to remove

Biofilm produces a protective polysaccharide shell that makes it difficult for traditional cleaning systems to remove.

It binds into the surface it attaches to by partially dissolving it.

Traditional cleaners are not able to fully penetrate the protective coating so they do not completely remove the biofilm, allowing it to quickly re-grow.

Impact of Biofilm

1. Your energy bills – reduced efficiency

Biofilm can dramatically affect the efficiency of commercial and industrial systems, with significant consequences for both your energy bills and the environment.

In the case of air conditioners, the biofilm that grows on the heat exchangers is an effective insulator. Because of this, the air conditioner will consume more electricity and in most cases, the system is unable to cool to the desired temperature.

Water circuits are often used in industrial applications such as mining. Any reduction in water flow affects the water circuit and often has a direct impact on the productivity of the site.

2. Your assets – widespread corrosion

Biofilm and their metabolic activities on a metal surface causes corrosion.

One cause of the corrosion is sulfate-reducing bacteria. By consuming oxygen the biofilm creates the perfect growing conditions for anaerobic bacteria such as sulfate-reducing bacteria to grow. The hydrogen sulfide produced by this bacteria are highly corrosive.

A second cause are acid-producing bacteria. Bacteria can produce aggressive acids that accelerate corrosion by dissolving oxides that protect metals.

3. Your health – and that of your workforce or family

Biofilm acts as a habitat for bacteria and pathogens. One well known example is Legionella. When the right environmental conditions exist Legionella bacteria increase from safe to harmful levels inside the biofilm. When released in sufficient quantities, these bacteria are potentially deadly.

Biofilm causes many other serious health effects. When biofilm lives on air conditioners, for example, it leads to poor indoor air quality (IAQ). The effects of compromised IAQ range from minor skin & eye irritations to asthma, allergies, respiratory complaints and suppression of the immune system.

This can have severe economic repercussions – both on the efficiency of your workforce, and the health costs for you and your family.

AerisGuard and Biofilm

AerisGuard works on biofilm in two ways:

1. Remediates

The enzymes in the AerisGuard cleaning solutions digest the linkages between the different organisms so that the biofilm can be easily removed
Many different types of enzymes are used to ensure sufficient digestion of the biofilm

2. Protect

On surfaces that are completely immersed in water AerisGuard protects by periodically applying the multi enzyme solution to prevent the build up of biofilm
On surfaces that are not completely immersed in water AerisGuard protects by the use of biostatic coatings, which are applied to surfaces such as air conditioner heat exchange coils and dissolve slowly over periods as long as 12 months to prevent biofilm formation