Environmental Monitoring Alert/Action levels.

Personnel Monitoring

In my last blog, I talked about viable surface, viable air, and non-viable particulate air environmental monitoring (EM) and the equipment used in these EM activities. However I didn’t talk about personnel monitoring. Manufacturing operators, who work in aseptic filling areas have to be sampled for microorganisms because most microbial contamination of product come from humans. Most of the time, operators’ gloved fingers and clean room garment on the chest area are touched with TSA plates and the plates are incubated and then checked for microbial growth. Personnel EM program is designed to monitor cleanliness of the operators who perform manufacturing activities in aseptic processing areas, such as the drug fill room. Personnel monitoring is usually done at the end of operators’ shifts inside the clean rooms to determine if operators’ gloves and clean room garment were contaminated during manufacturing operations.


Alert and Action levels

Out of specification EM results are classified either as alert level or action levels. According to University of Florida’s Center of Excellence for Regenerative Health and Biotechnology, alert levels are “quality levels that, when exceeded, signal a possible deviation from normal operating conditions and may not require action, but may need to be monitored more closely” and action levels are “quality levels that, when exceeded, signal an apparent deviation from normal operating conditions and require immediate action”.

Every type of EM program; viable air, viable surface, non-viable particulate air, and personnel gown monitoring all have alert and action levels. Alert and action levels are set depending on the clean rooms in which samples are collected. Until recently, Pharmaceutical manufacturing clean rooms are generally classified as per the US Fed Std 209E as class 100, class 1000, class 10,000, and class 100,000 depending on the level of cleanliness of the rooms and type of manufacturing activities take place. For example, in class 100 room, the action level limit is 99 particles greater than or equal to 0.5 um / ft3. Although the US Fed Std 209E was officially replaced by ISO 14644-1, its terminology is still widely used in most of US pharmaceutical plants. ISO 14644-1 classifies clean rooms as ISO class 5, 6, 7, and 8. If a plant manufactures drugs to export to the European Union, then its clean rooms must be classified according to EU Annex I regulations. EU Annex I classifies clean rooms as classes A, B, C, and D. Since Class 1000/ISO 6/EU Class B rooms are not widely used in the pharmaceutical manufacturing, I will not mention the Alert and Action levels for this class. The four tables below present typical alert and action levels for non-viable particulate air, viable air, and viable surface EM. Every firm has alert/action levels not so different from these values below.

Action Level Alert Level
US Fed Std 209E EU Grade ISO 14644-1 ≥ 0.5 µm particles/ft3 ≥ 0.5 µm particles/m3 ≥ 0.5 µm particles/ft3 ≥ 0.5 µm particles/m3
Class 100 A Class 5 100 3,500 80 2800
Class 10,000 C Class 7 10,000 350,000 7000 245,000
Class 100,000 D Class 8 100,000 3,500,000 40,000 1,400,000
Table 1: Non viable particulate air Alert/Action levels
US Fed Std 209E EU Grade ISO 14644-1 Viable air Alert level (CFU/test)

Viable air Action level
(CFU/test)
Class 100 A Class 5 1 5
Class 10,000 C Class 7 13 15
Class 100,000 D Class 8 113 125
Table 2: Viable Air Alert/Action Levels
CFU/test means colony forming units recovered during a 50 minutes sampling period.


US Fed Std 209E EU Grade ISO 14644-1 Viable Surface Alert Viable Surface Action
Class 100 A Class 5 1 2
Class 10,000 C Class 7 2 // 5* 4 // 8*
Class 100,000 D Class 8 2 // 10* 4 // 13*
Table 3: Viable Surface Alert/Action Levels; walls & work surfaces//floors*


In classes 10,000 and 100,000, alert/action levels are different for walls and work surfaces and floors. Alert/action levels on the walls and work surfaces are lower than that of the floors. Recovery of objectionable microorganisms will prompt an action level deviation. An objectionable microorganism is a bacteria or mold that adversely impacts product quality, stability, and patient safety. Some examples of objectionable microorganisms are gram-negative bacterium such as Escherichia coli, gram-positive bacterium such as Staphylococcus aureus, and mold such as Aspergillus niger.


Action Level Alert Level
US Fed Std 209E EU Grade ISO 14644-1 Personnel Monitoring Gloved Finger tips Personnel Monitoring Cleanroom garment Personnel Monitoring Gloved Finger tips Personnel Monitoring Cleanroom garment
Class 100 A Class 5 1 3 N/A 1
Class 10,000 C Class 7 N/A N/A N/A N/A
Class 100,000 D Class 8 N/A N/A N/A N/A
Table 4: Personnel Gown Monitoring Alert/Action levels

Operators, quality control, and maintenance personnel who enter Class 100 aseptic processing or filling rooms have to be sampled for microorganisms at the end of their shifts before they exit the aseptic areas. Finger-tips and clean room garment on wrist and chest areas are usually sampled on a routine production day.