Assessment of Temperature Hazard
| Hazard | Sub-Factors | Description and Reason | Weighting/Score |
|---|---|---|---|
| Temperature severity | Freezer | Freezing has micro-static effect. Sometimes freezing has a micro-cidal (or at least the process of freezing-thawing). There is very little probability of microbial growth or of a high level of environmental contamination. Therefore, this factor has been awarded the lowest weighting. | 0 |
| Cold (typically 2–8 °C) | Cold temperature has a micro-static effect on most micro-organisms (with the exception of psychrophilic microorganisms, which can typically grow between 5 and 15 °C, or psychrotolerant micro-organisms, which can survive at such temperatures). A review of typical micro-flora indicated that such micro-organisms were rarely recovered, and where they are they normally have been associated with water. Consequently the weighting for this factor is above freezing but below ambient conditions. | 1 | |
| Ambient (typically 18–25 °C) | This is the temperature range at which most micro-organisms common in the environment can grow and survive at (mesophilic micro-organisms, typical growth between 25 and 40 °C). Consequently this has been given the highest weighting. | 3 | |
| Warm (typically with periods of ≥30 °C, e.g., autoclave preparation area) | There are some process rooms that are relatively warm (such as those containing autoclaves). The environment in these areas is theoretically slightly less likely than rooms at ambient to support microbial growth. Therefore a lower weighting has been applied to these rooms. | 2 |