Chamber Temperature & Humidity Distribution Test for ETO Sterilizers
Detailed procedures for measuring internal surface temperature and mapping temperature/humidity within the usable space of an ethylene oxide sterilizer – essential for compliance with performance specifications.
Inquire via WhatsApp ? View ETO Sterilizer ProductAccurate temperature and humidity distribution testing is critical to verify that an ETO sterilizer meets the uniformity requirements outlined in the ETO sterilizer performance specifications. These tests ensure that every load area reaches and maintains the conditions necessary for effective sterilization.
Measurement Requirements
Use temperature recording instruments that comply with Temperature Accuracy standards. Record the temperature of representative areas on all heated internal surfaces.
Sensor Placement
Place at least one synchronized measurement point on each heated surface (e.g., a minimum of 6 points for 6 heated surfaces). Additionally, provide at least one synchronized point for every 5 m³ of heated internal surface area. Document the exact location of each sensor.
Test Conditions: Perform this test with an empty chamber and the door closed, though auxiliary devices normally used during sterilization may be present. Begin recording after the manufacturer’s specified preheating phase. Maintain the heating control system active at atmospheric pressure for a duration no shorter than the longest sterilization cycle at the set temperature. (Testing in standby mode is acceptable.)
The results must satisfy the Surface Temperature Uniformity criterion, which requires all internal surface temperatures to remain ? setpoint +5°C.
Sensor Configuration
Temperature and humidity sensors must meet the accuracy defined in Temperature Accuracy ಮತ್ತು Relative Humidity Accuracy. The minimum number of sensors depends on chamber volume, as shown in Table C.1 below. Use the larger calculated value when both temperature and humidity requirements are considered.
Test Execution
The chamber must be empty (auxiliary devices allowed) and the door closed. During a typical sterilization cycle, measure and record temperature and humidity at all sensor locations. For safety, it is recommended to use non-toxic, non-flammable gas or gas mixtures instead of ethylene oxide during this test.
Minimum Number of Sensors (Table C.1)
| Chamber Volume (m³) | Min. Temperature Sensors | Min. Humidity Sensors |
|---|---|---|
| ?1 | 3 | 2 |
| 10 | 10 | 4 |
| 15 | 15 | 6 |
| 20 | 20 | 8 |
| 25 | 25 | 10 |
| 30 | 30 | 12 |
| 35 | 35 | 14 |
| 40 | 40 | 16 |
| 50 | 50 | 20 |
| 100 | 100 | 40 |
The recorded data must demonstrate that the usable space temperature uniformity meets the Usable Space Temperature Uniformity requirement of ±3°C from the setpoint. Humidity should be monitored to confirm proper conditioning as per the sterilization cycle design.
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WhatsApp ನಲ್ಲಿ ಚಾಟ್ ಮಾಡಿDisclaimer: This article summarizes general temperature and humidity distribution test procedures for educational purposes. Always follow the manufacturer’s instructions and applicable standards for specific validation protocols.