Routine environmental monitoring ensures a safe compounding environment and is used to test for viable and nonviable particle levels. Environmental monitoring includes testing the temperature, pressure differential, nonviable particles, surface sampling, and viable electronic device sampling at least every six months. It also involves monitoring humidity, sound, and lighting levels. Environmental sampling should occur throughout the entire compounding area including the ISO Class 5 PEC, buffer areas, ante-areas, and segregated compounding areas.

1. Environmental Monitoring
Requirements – An Introduction

2. Routine environmental monitoring ensures a
safe compounding environment

3. Environmental monitoring is used to ensure that
the compounding area has acceptably low viable
and nonviable particle levels.

4. Nonviable particles are particles that do not
contain a living organism, i.e. dust or particles
shed from paper

5. Viable particles are items such as bacteria or
fungal spores. Viable particles require nonviable
particles to travel

6. Monitoring of humidity, sound, and lighting
should also be considered

7. Environmental sampling should include the entire
compounding area: ISO Class 5 PEC, buffer areas,
ante-areas, and segregated compounding areas

8. Environmental sampling shall occur as part of a
comprehensive quality management program

9. Environmental sampling frequency shall
occur at a minimum of:
• At commissioning and certification of new facilities and
equipment
• Every six months as part of the re-certification of facilities
and equipment
• Following any facility or equipment maintenance
• If/when issues are identified with the the sterile
compounding process (work practices, aseptic technique,
potential infection)

10. Environmental monitoring required by USP
Chapter <797> include

11. Temperature Documented daily
Pressure differential or velocity across the
line of demarcation
Documented daily at a minimum
Preferably each shift
Nonviable particles Performed at least every 6 months
Surface sampling Performed at least every 6 months
Electronic device sample of viable
particles
Performed at least every 6 months
Table adapted from: American Society of Health-System Pharmacists. ASHP Guidelines on Compounding Sterile Preparations. Am J Health-Syst Pharm. 2014;71:145-66

12. JERRY FAHRNI, PHARM.D.