Destructioning the ozone produced by the corona treatment

The corona treatment stations produce ozone (Oa polluting molecule) that does not dissolve in the air, increases the levels of photochemical smog and can be detrimental to human health.

The amount of ozone produced by the corona treaters and emitted into the atmosphere depends on the environment (humidity, temperature and pressure) and the physical characteristics of the system and processing (surface discharge, type of electrode, the value of power used, capacity and air suction speed).

Ferrarini & Benelli has designed and built the innovative Ozo-no! catalytic multi-stage destruction system at room temperature that overcomes the limitations of traditional destruction systems with activated charcoal.

The table attached shows the results of an American study, which looked at ozone effects on humans.

Ozone Concentration into Air

Symptoms & Reactions




0.02 ÷ 0.04

0.01 ÷ 0.02

Smell threshold.



Strong odour, nose and throat irritation.

0.4 ÷ 1

0.2 ÷ 0.5

Eyesight troubles after having been exposed for some hours.



Serious trachea problems.

2 ÷ 4

1 ÷ 2

Headache, pains to chest, thirst. Strong irritation of trachea. A long exposure provokes poisoning.

10 ÷ 20

5 ÷ 10

Sense of suffocation. Pulmonary edema.

30 ÷ 40

15 ÷ 20

Small animals normally die after 2 hours.



Coma for men after 1 hour exposure.

Safety of workers and the environment

The ozone is an unstable molecule with three oxygen atoms. It is one of the strongest oxidants and participates actively in the complex of photochemical reactions in the atmosphere with nitrogen oxides and hydrocarbons.

In relation to the possibility that ozone may  combine with other elements with a detrimental effect and to define the measurement techniques and analysis as well as the threshold of ozone concentration in the air, the following have been issued:

  • Directive 92/72 EEC dated 21.9.1992
  • Decree 15/04/94
  • Decree 16/05/96 of the Italian Ministry of Environment.

The presence of ozone produced by corona treatments should be considered from two points of view:

  • safety for workers in the work environment where ozone is produced
  • safety for the external environment (chimney emissions of ozone from corona treatment).

To enable our customers to comply with regulations to protect the environment and improve working conditions, we have studied and created systems that suck in and exhaust ozone produced from the stations of corona treatment, in an optimal way.

In the case of corona treaters with rollers or ceramic electrodes, ozone production is about 3-5 times higher than that of traditional corona treatment with silicone insulation.

Threshold limits for ozone emissions in chimney

This threshold value can change from city to city; there are still no harmonised European standards in this regard. In Italy the provisions of the Regions are valid. We describe here following how is the provisions and procedures in Italy. Please check which are the provisions in your country.

In Italy, according to DPR 203/88 and subsequent amendments and national and regional decrees enacted, all companies must submit authorisation requests to the competent Regions for the release of pollutants produced into the atmosphere. This authorisation must also be requested for ozone.

The Regions therefore establish the maximum threshold for ozone emission permitted for each business. This threshold depends on the concentration of emissions in the area.

The customers have to submit the application for authorisation related to atmospheric emissions of ozone to the associated office of the pertinent municipality and the ARPA offices of the pertinent Province. These institutions determine the maximum permissible concentration of emissions and the Air and Environmental Control Service of the pertinent Province issues the relevant authorisation. The threshold imposed by certain Italian Regions on our customers was 2-4 mg/Nm3 but there are some regions that have imposed values ​​below 1 mg/Nm3

Destructioning the ozone produced by the corona treatment