Dry-bulb temperature
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 measured by a thermometer exposed to the air but shielded from radiation and moisture. It can be expressed in Celsius (C), Fahrenheit (F) or Kelvin (K).
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).
[edit] Related articles on Designing Buildings
Featured articles and news
International Women's Day 8 March, 2025
Accelerating Action for For ALL Women and Girls: Rights. Equality. Empowerment.
Lack of construction careers advice threatens housing targets
CIOB warning on Government plans to accelerate housebuilding and development.
Shelter from the storm in Ukraine
Ukraine’s architects paving the path to recovery.
BSRIA market intelligence division key appointment
Lisa Wiltshire to lead rapidly growing Market Intelligence division.
A blueprint for construction’s sustainability efforts
Practical steps to achieve the United Nations Sustainable Development Goals.
Timber in Construction Roadmap
Ambitious plans from the Government to increase the use of timber in construction.
ECA digital series unveils road to net-zero.
Retrofit and Decarbonisation framework N9 launched
Aligned with LHCPG social value strategy and the Gold Standard.
Competence framework for sustainability
In the built environment launched by CIC and the Edge.
Institute of Roofing members welcomed into CIOB
IoR members transition to CIOB membership based on individual expertise and qualifications.
Join the Building Safety Linkedin group to stay up-to-date and join the debate.
Government responds to the final Grenfell Inquiry report
A with a brief summary with reactions to their response.
A brief description and background to this new February law.
Everything you need to know about building conservation and the historic environment.
NFCC publishes Industry White Paper on Remediation
Calling for a coordinated approach and cross-departmental Construction Skills Strategy to manage workforce development.
'who blames whom and for what, and there are three reasons for doing that: legal , cultural and moral"