Background and importance The activity of chemotherapy preparations is constantly evolving:

1. It is increasing (+17% in our centre in 5 years).

2. Particulate quality monitoring is recommended but rarely done in hospital pharmacies.

The pharmacist, who is responsible for this activity, must anticipate these changes.

Aim and objectives We first demonstrated the compliance of our controlled atmosphere area with the ISO 7 (at rest) and ISO 8 (during activity) criteria. Then we determined the factors significantly impacting on the particle rate in order to design a mathematical model that would predict the number of particles and thus better control the increase in activity.

Material and methods The particle count was carried out according to the requirements of the ISO 7 and ISO 8 standards (particle size, sampling plan, volume, duration and height). We systematically recorded the following factors: date, time, number of people present in the controlled area, temperature, pressure, sampling location, sampling conditions (at rest or during activity) and equipment entering the ZAC mechanically cleaned or not. For the statistical analysis, a grouping of sampling points by critical sector (personnel entry and exit area, work area itself, material transfer and basket preparation area) was carried out. Data were analysed to perform the multivariate models required for predictive mathematical modelling (significant variables at the p=0.05 threshold).

Results All 994 samples (from 16 counting points) in our 80 m² depressed area complied with the ISO 7 and ISO 8 criteria for particulate contamination. Predictive mathematical modelling of the number of particles was based on the significant criteria ‘time of day’, ‘location of sampling’ and ‘number of people’.

Conclusion and relevance Particulate quality criteria were met at rest and especially during activity (which is rarely evaluated). These results could be related to the technical quality of the air plant (all new air and 25 air changes/hour) and the materials and characteristics of the PPE used (low particle release). By taking into account the factors integrated in the mathematical models, smoothing the number of people over the day and increasing the cleaning of risk areas, it will be possible to guarantee and better understand the particular quality of our areas.

References and/or acknowledgements No conflict of interest.