- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 13 Nov 2015
Dry-bulb temperature (Tdb, DBT or Td), is a measure of air temperature. It is referred to as dry-bulb temperature because the thermometer bulb is dry and so the temperature recorded does not vary with the moisture content of the air. This is as opposed to wet-bulb temperature which is the temperature recorded by a thermometer that has its bulb wrapped in cloth and moistened with distilled water. Wet-bulb temperatures are the same as dry-bulb temperatures at a relative humidity of 100%, but otherwise wet-bulb temperatures will be lower than dry-bulb temperatures due to the cooling effect of evaporation (described as wet-bulb depression).
A sling psychrometer holds both wet and dry-bulb thermometers and can be used to express the physical and thermal properties of moist air on a psychrometric chart.
Dry-bulb temperature can be used as to express a component of thermal comfort. For example, the wet bulb globe temperature index (WBGT) is widely used for the assessment of heat stress and combines wet-bulb temperature, dry-bulb temperature and globe temperature (mean radiant temperature).
 FIND OUT MORE
 Related articles on Designing Buildings Wiki
Featured articles and news
Do you understand the different types of stone and which ones you should use where?
Why a wellbeing strategy is vital for property managers.
An ECA briefing for members about the commercial implications of leaving the EU.
A crucial moment on any project - and fraught with danger.
The performance gap from a Northern Ireland perspective.
Book review: Buildings of protestant nonconformity.
Design and testing for health and wellbeing - free download from BRE.
Retention in construction contracts.
Campaign for the reform of cash retentions.
The key points for the construction industry and BSRIA's response.
How to make roads safer: the debate continues.