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TcAF technology

Avidicare uses a patented technology called
Temperature-controlled AirFlow (TcAF)

This technology enables Opragon to use gravity to reliably control the temperature of the airflow in operating rooms and thereby reduce bacteria-carrying particles in the whole room. More clearly; TcAF creates a more reliable and effective ventilation system than a LAF (Laminar Airflow) ceiling, which requires higher air speeds to counteract the convection currents from the staff and equipment. Compared to traditional mixing ventilation systems, Opragon needs less air to maintain ultra-clean conditions, while allowing more comfortable operating clothes

TcAF is a unique way to move airborne contaminants from their source to somewhere where they do no harm with very high ventilation efficiency.

The limitations of LAF ceilings

The European hospital standard for ultra-clean ventilation systems was previously LAF ceilings. The drawback of these LAF ceilings is that they take up a large proportion of the ceiling surface and often need higher air speeds to be able to counteract the bacteria flow in the operating room. Higher airspeeds of course also mean higher use of energy, which costs money, harms nature and produces noise and draught that disturb the surgical team and it has also been difficult to show improved outcomes. Furthermore, a LAF ceiling only protects the middle of the room, while Opragon keeps the whole room ultra-clean.

It should be noted that low-speed LAF systems such as those commonly used in the US technically do not produce a laminar airflow and thus has a reduced protective effect.

The drawbacks of mixed ventilation systems

Traditional mixed ventilations systems are not able to reliably create and maintain ultra-clean conditions during surgery, especially at lower air change rates (20 ACH). Even with very high rates (60 ACH), ultra-clean is only reliably achieved in combination with very tight clothing systems. This has a negative impact on comfort, safety and cost.  

How does TcAF work?

To ensure that the air in the operating room remains uncontaminated, the convection flows from the staff and equipment must be broken. Otherwise, there is a risk of uncontrolled airborne bacteria dissemination. Ventilaton systems with a lower air speed pose a greater risk of not removing bacteria-carrying particles, which can lead to contamination of the air in the operative zone. Higher speeds, on the other hand, cause draught, noise, dehydration of the patient and staff, cooling of the patient, and turbulence that reduces the effect of the laminar airflow. These limitations of existing technology is precisely why we developed Opragon, which combines the classic mixed/diluting ventilation (which dilutes the number of bacteria-carrying particles) with a cooled unidirectional airflow. Combining the two systems in the same operating room produces extremely effective ventilation. 

The technology behind TcAF is based on the ventilation system pumping out slightly cooled air into a zone around the operating table. By taking advantage of the fundamental laws of nature, TcAF breaks the convection currents in an effective and energy-efficient manner. Since cool air is denser than the surrounding warmer air, it drops towards the floor. The air speed is dictated by the temperature difference in the room. The system enables reliable and stable control of air movements, and thereby also the airflow’s fall speed over the patient and the sterile-clad staff. The technology reduces the presence of bacteria-carrying particles in the operative zone while at the same time helping to create a comfortable working environment. It makes the temperature slightly cooler for sterile-clad staff and slightly warmer for other staff in the room. The temperature can be set to any level that is required by staff or the patient. Discover Opragon here.

The temperature difference dictates the speed

If the air, coming from the ventilation system, is cooler than the layer of air at the level of the operative zone, the ultra-clean air will drop down to the operative zone and thereby provide its protective effect. The convection currents are broken and the airborne bacteria are transported away from the patient and the sterile instruments. In order for the ultra-clean air to reach the operative zone, there must be a fall speed of about 0.25 m/s at the level of the operative zone. The speed at the operating table will vary depending on the temperature difference between the ultra-clean air and the ambient room air in the operating room. 

During the development of Opragon, we determined that a temperature difference (ΔT value) of -1.5 to -3°C is required between the ultra-clean air and the ambient room air at the operating table to guarantee a fall speed of about 0.25 m/s at the level of the operating table. The technology continually checks to ensure that the ultra-clean air maintains a constant under-temperature of 1.5–3°C regardless of the temperature of the ambient room air.

Independent scientific validation confirms real life advantages

An extensive set of scientific evidence has been gathered during the last 15 years since the very first installation of an Opragon using TcAF. The key findings confirm less than 10 cfu/m3 as well as ISO 5 or better in the whole OR. The low noise and minimal draught are also verified along with the low energy consumption. Read more here.

Opragon is more than capable of meeting air quality requirements for general surgery at airflow levels down to 50% of the airflow required for ultra- clean conditions. Air flow rates in operating rooms equipped with Opragon can be easily adjusted to the type of surgery, conserving energy during lower risk procedures. When conditions change, such as a need for infection sensitive surgery or a viral outbreak, the ultra- clean mode of Opragon will add safety. 

Yes, you can equip all your operating rooms with a ventilation system that optimizes both safety and energy use. 

Contact us to get more information about the performance of Opragon at 20, 25, 30 and 40 air changes per hour (ACH). 

Technical specifications document

Please contact us to receive the Technical specifications document.