Cleaning, disinfection and environmental monitoring

Why Cleaning and Disinfection Matter

Compounding areas—whether non-sterile, sterile, or hazardous—must be kept free of microbial contamination, chemical residue, and particulate matter. Errors in cleaning order or agent selection can introduce contamination into a patient's medication, cause drug interactions on surfaces, or expose technicians to hazardous drug residues. USP <795> governs non-sterile compounding, USP <797> governs sterile compounding, and USP <800> governs hazardous drug handling. All three chapters include requirements for cleaning, disinfection, and environmental monitoring.

The Difference Between Cleaning and Disinfecting

Cleaning physically removes dirt, debris, and organic matter. It does not kill microorganisms on its own, but it is a required first step because leftover organic matter blocks the action of disinfectants.

Disinfecting kills or inactivates microorganisms on a surface that has already been cleaned. Applying a disinfectant to a dirty surface is never acceptable—the organic load prevents effective kill.

Sporicidal agents go one step further and destroy bacterial spores. USP <797> requires periodic use of a sporicidal agent in sterile compounding areas because many routine disinfectants do not kill spores.

Correct Cleaning Sequence

Always work from clean to dirty and from high to low:

1. Remove loose debris — wipe down or pick up visible particles or waste first.

2. Apply cleaning agent (e.g., sterile water or a detergent solution) — wipe surfaces to remove organic matter. Allow contact time as directed.

3. Apply disinfectant (e.g., sterile 70% isopropyl alcohol, or IPA) — wipe surfaces in overlapping, one-directional strokes. Do not go back over an area with the same stroke.

4. Apply sporicidal agent on the required schedule — in sterile compounding areas this is done periodically (for example, monthly or as the facility's written procedures specify).

5. Allow all agents to air-dry before beginning any compounding. Wet surfaces can harbor contamination and interfere with compounding.

Within a cleanroom, work from the cleanest zone outward: clean the direct compounding area (DCA) or laminar airflow workbench (LAFW) interior first, then ante-areas last.

Agents Used

| Agent | Primary Use | Key Note |

|---|---|---|

| Sterile 70% IPA | Disinfection of surfaces and gloved hands | Most common routine disinfectant in sterile areas |

| Sterile water or detergent | Cleaning (step 1) | Must precede disinfection |

| Sporicidal agents (e.g., accelerated hydrogen peroxide products) | Periodic sporicidal step | Rotate agents to prevent resistance |

| Deactivating/decontaminating agents for hazardous drugs | HD spill cleanup and routine decontamination | Required under USP <800> before disinfection |

For hazardous drug areas covered by USP <800>, a deactivation step (breaking down the drug's chemical structure) and a decontamination step (removing residue) precede cleaning and disinfection. The sequence for HD areas is: deactivate → decontaminate → clean → disinfect.

Personal Protective Equipment During Cleaning

Always don appropriate PPE before cleaning:

• Sterile compounding areas: low-lint gown, hair cover, face mask, shoe covers, and sterile gloves.
• Hazardous drug areas: chemotherapy-rated (chemo) gloves (often double-gloved), gown rated for HD protection, and eye/face protection if splashing is possible.
• Never clean a hazardous drug area without HD-rated PPE, and never use the same cleaning materials from an HD area in a non-HD area.

Environmental Monitoring

Environmental monitoring (EM) verifies that cleaning is working. Two common EM methods used in compounding pharmacies are:

Surface sampling (contact plates or swabs): A sampling plate (often called a RODAC plate—Replicate Organism Detection and Counting) is pressed firmly against a surface and then incubated. Growth of colonies indicates contamination. Swabs can reach difficult spots.

Air sampling (settle plates or active air sampling): Settle plates are opened and exposed to the air for a set time, then incubated. Active air samplers pull a measured volume of air over a collection surface. Both methods detect airborne viable organisms.

Sampling sites are specified in the facility's written procedures and typically include the interior of the LAFW or biological safety cabinet (BSC), gloved fingertips of compounding personnel, and other high-risk surfaces.

Documentation

Every cleaning event must be recorded in a cleaning log that captures:

• Date and time
• Area or equipment cleaned
• Agents used (name, lot number, and expiration date)
• Name of the person who performed the cleaning
• Results of any EM samples taken

Incomplete or falsified logs are a serious compliance and patient-safety violation. If EM results exceed action limits, the pharmacy must investigate, increase cleaning frequency, and document corrective actions.

Safety Reminders

• Never mix cleaning agents unless the manufacturer explicitly says they are compatible.
• Dispose of HD-contaminated cleaning materials as hazardous waste.
• Report any spills of hazardous drugs immediately following the facility's spill kit procedure before resuming cleaning.
• If a cleaning agent expires or is improperly stored, discard it—compromised agents cannot ensure patient safety.