ΠΙΣΤΟΠΟΙΗΣΗ OZOTEK ΣΕ SUPERMARKET – ΠΑΤΗΣΤΕ ΕΔΩ ΓΙΑ ΠΡΟΒΟΛΗ ΟΛΟΥ ΤΟΥ ΑΡΘΡΟΥ
4. Materials and Methods
4.1. Study Design
Surveys were conducted in four supermarkets belonging to the same commercial
chain, selected from the most representative ones of an Apulian city in June 2021. Of these,
two (hereinafter referred to as A and B) were equipped with an ozonation system, and two
(hereinafter referred to as C and D) did not have any air-diffused remediation treatment.
The ozonation systems in the two supermarkets are equipped with two or three
generators (GX model, Ozotek®, Taranto, Italy), with closed corona discharge reactors,
located in false ceilings with branches for the distribution of ozone in the selling areas. By
means of microcompressors, the machines produce approximately 2.64 g ozone per hour.
During the night, in the absence of staff or customers, cycles of ozonation are carried out
for a total of 2 hours and 30 minutes. During the opening hours, microcycles of 10 minutes
are performed every 2 hours, from 8:00 am to 6:00 pm. The staff can access workplaces at
7:00 am, and shops are opened to customers at 8:00 am.
The sampling was carried out over four consecutive midweek days (one for each
supermarket) not holidays, in order to reproduce conditions as reproducible as possible
and with medium turnout. The areas most frequented by customers were selected for
air sampling: bread, cheeses, cured meats, fish, fruit, vegetables and checkout areas; for
surfaces sampling, scales for self-service products, refrigerator handles for beverages and
dairy products, freezer handles for ice cream, cash register keyboards used by cashiers and
POS keyboards used by customers were selected.
The samples were taken at opening hours (8:00 am) and at the most representative time
of the high levels of customer use (12:00 pm), transported to the laboratory in a suitable
isothermal refrigerator at a controlled temperature (4 C) and immediately processed.
Overall, 10 air and 20 surface samples were examined for each supermarket both at 8:00 am
and at 12:00 pm, for a total of 240 samples (80 of air and 160 of surfaces).
