Temperature and Humidity mapping of a controlled enclosure
What is a temperature/humidity controlled enclosure?
“Any device which provides a space in which temperature and/or humidity is controlled. Temperature controlled enclosures are designed to maintain a specific temperature and humidity within their working volume, and must not expose their contents to conditions beyond their tolerance limits. It is essential to verify that the enclosure is capable of meeting these tolerances. This is achieved by performing a temperature and humidity mapping of the working volume.” – NSAI Guide to Mapping Enclosures 2012.
What is ‘Mapping’?
Sample temperature and humidity report from mapping
Mapping refers to creating a temperature and humidity plan of an enclosure. Through placement of multiple temporary recording devices (dataloggers), a user is able to see the temperature and humidity for each chosen location of a room. This information can then be combined to allow comparisons of the consistency throughout an enclosure. Should the results of a mapping show inconsistencies between different locations, the maintenance team should be consulted. Options available include adjusting ducting or recalculating required number of air changes per hour. The enclosure should be remapped after any changes to the layout of the room or the equipment.
Why Map?
Homogeneity: Most controlled enclosures will have two monitoring probes, continually feeding results back to a Central Monitoring System, from two set locations within the enclosure. A mapping provides this same information across a multiple of locations within the enclosure, and thus, ensures the Central Monitoring System reflects the conditions within the enclosure. If there are any ‘cold’ or ‘hot spots’ present, they will be immediately visible as the results from all dataloggers are compared.
Environmental effects: Through the placement of an external datalogger, adjacent to the enclosure, variations in environmental temperature and humidity can be recorded. This information can be cross referenced with the internal results to check if the operating conditions are having an effect on the performance of a room.
The Process?
Sample enclosure showing location of each datalogger
Assessment: Assess the layout and size of the room to calculate the number of dataloggers required. A 3 dimensional plan of the room,
detailing any shelving/racking can be a useful way of ensuring all working areas are being captured. Clearly mark each location on the map, recording the assigned datalogger to each location (seen right).
Dataloggers: Once the number of dataloggers required is known, the correct datalogger must be chosen. If the room has temperature and humidity control, the datalogger must have the capability to record both. Calibration certificates for each datalogger must be provided, to confirm no certificate has passed its expiry date.
Protocol: A protocol should be created detailing the enclosure to be mapped, duration of mapping, number of dataloggers and locations. The acceptance criteria should be clearly detailed, providing instructions on the steps to be followed, if the mapping is deemed to have failed.
Final Report: When the mapping has been completed, a detailed report should be presented, either as a separate document or as an attachment to the protocol. Report should detail minimum, maximum and mean results for each datalogger, across the duration of the mapping. If possible all loggers should then be combined into one graph to clearly highlight any ‘outlier’ results.
Optional Extras:
Recovery Rate: If required, door openings can be included into the mapping process. The protocol should allow for clear recording of the time and duration of door openings. The acceptance criteria will need to be adjusted to allow for this.
Time to reach set conditions: For new or empty enclosures, mapping can be used to establish the time take from ‘power on’ to reach required set point.
A mapping should be completed on any temperature or humidity controlled equipment before it is introduced and used on site. It is advisable to continue to map all temperature and humidity controlled enclosures annually to ensure consistency of performance.
We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept”, you consent to the use of ALL the cookies. However you may visit Cookie Settings to provide a controlled consent.
This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may have an effect on your browsing experience.
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.