Thermal microclimate PMV PPD WBGT – HD32.3TC

The thermal microclimate datalogger is a portable instrument for the analysis of thermal comfort, microclimatic indices and indoor air quality IAQ. It allows the measurement and calculation of key parameters such as WBGT, PMV, PPD, DR, TU, HI, UTCI, TEP, as well as environmental quantities such as CO2, VOC, PM1.0, PM2.5 and PM10, depending on the connected probes.

The instrument is designed for assessments in moderate environments, severe hot environments, cold environments and indoor areas where temperature, humidity, air velocity, radiant heat, ventilation and air quality can affect human comfort. It is therefore suitable for analysis in offices, schools, production areas, laboratories, public buildings, industrial departments and HVAC systems.

The PMV and PPD indices are used to assess overall thermal comfort, based on the predicted mean vote and the predicted percentage of dissatisfied occupants. The WBGT index is used for the evaluation of heat stress, while DR and TU help assess local discomfort caused by draughts and turbulence. The UTCI and TEP indices provide a more complete interpretation of perceived temperature in relation to the surrounding environmental conditions.

The range includes the HD32.3TC version, which is more portable and often used with a table stand or small tripod, and the HD32.3TCA configuration, suitable for longer measurement periods with a stable tripod. The main difference concerns the probe connection and the globe thermometer: in the HD32.3TC version, the sensors are connected directly to the top of the instrument and the globe thermometer has a diameter of 50 mm; in the HD32.3TCA configuration, the sensors are connected by cable and a 150 mm globe thermometer is used.

Depending on the configuration, the datalogger can simultaneously measure ambient temperature, globe temperature, natural wet bulb temperature, relative humidity, air velocity, atmospheric pressure, CO2, VOC index and particulate matter PM1.0, PM2.5 and PM10. Some indices require a combination of several probes; for example, WBGT measurement requires ambient temperature, globe temperature and natural wet bulb temperature.

The colour LCD touchscreen makes the measured values and calculated indices easy to read. Dedicated screens allow the user to view the results directly and, for certain indices such as PMV/PPD, Heat Index, UTCI and TEP, a coloured bar helps interpret the thermal stress level. Real-time graphical display of two quantities is also available, with the possibility to set scales, reference thresholds and visual alarms.

The 8 GB internal memory allows long measurement cycles, with a logging interval configurable from 1 second to 1 hour. The rechargeable lithium-ion battery guarantees an operating autonomy of at least 24 hours, even under high-consumption conditions. Data can be exported in PDF and CSV format using DeltaLog10 software.

Connectivity includes USB host and device, powered RS485 for auxiliary probes and Wi-Fi. The Wi-Fi connection allows data to be sent to an FTP server, making measurements available remotely. The built-in camera also allows images of the monitored environment to be stored, which is useful when measurement data need to be linked to the real context in which they were recorded.

The instrument can also estimate the natural decay time of SARS-CoV-2 on surfaces, based on ambient temperature and relative humidity values, according to the equation published by the U.S. Homeland Security Department. This function does not replace a health assessment, but provides an additional indicator in indoor environmental analysis.

The datalogger complies with the main technical standards for the ergonomics of thermal environments and the measurement of physical quantities: ISO 7726, ISO 7730, ISO 7243, ISO 9886, ISO 8996 and ISO 11079. It is therefore suitable for professional assessments of microclimate, thermal stress and comfort in workplaces and occupied spaces.

Applications

• Assessment of thermal comfort in moderate environments using PMV and PPD indices
• Measurement of heat stress using the WBGT index
• Analysis of cold environments using IREQ, DLE, RT and WCI indices
• Assessment of draught discomfort through DR and local turbulence intensity TU
• Indoor air quality monitoring in schools, offices, factories, laboratories and public buildings
• Verification of the efficiency of HVAC, heating, ventilation and air-conditioning systems
• Monitoring of CO2, VOC, relative humidity, atmospheric pressure and ambient temperature
• Measurement of particulate matter PM1.0, PM2.5 and PM10 with a dedicated probe
• Analysis of sick building syndrome and indoor comfort conditions
• Long-term measurement campaigns with datalogger, internal memory and remote data transmission

FAQ – Thermal microclimate PMV PPD WBGT

What is a thermal microclimate instrument used for?
It is used to measure and calculate the indices that describe thermal comfort, heat stress, draught discomfort, perceived temperature and indoor air quality. It is used in workplaces, offices, schools, laboratories and production areas.

Which microclimatic indices can it calculate?
The instrument can calculate WBGT, PMV, PPD, DR, TU, HI, UTCI, TEP, PHS, IREQ, DLE, RT and WCI, depending on the connected probes and the configuration used.

What is the difference between PMV and PPD?
PMV indicates the predicted mean thermal sensation vote of a group of people. PPD indicates the predicted percentage of people dissatisfied with the measured microclimatic conditions.

What is the WBGT index used for?
The WBGT index is used to assess heat stress. It is particularly useful in workplaces where temperature, humidity, radiant heat and ventilation can create critical conditions for operators.

What is the difference between HD32.3TC and HD32.3TCA?
HD32.3TC is the more portable version, often used with a table stand or small tripod, with sensors connected directly to the instrument and a 50 mm globe thermometer. HD32.3TCA is designed for more stable configurations and longer measurements, with sensors connected by cable and a 150 mm globe thermometer.

Which probes are required to calculate the indices?
It depends on the index to be measured. Some parameters require only one probe, while others require a combination of probes. For example, WBGT requires ambient temperature, globe temperature and natural wet bulb temperature.

Does the instrument also measure indoor air quality?
Yes, with dedicated probes it can measure CO2, VOC, relative humidity, atmospheric pressure and particulate matter PM1.0, PM2.5 and PM10. This allows the microclimatic assessment to be integrated with IAQ parameters.

Can data be recorded over long periods?
Yes, the 8 GB internal memory, configurable logging interval and autonomy of at least 24 hours allow long measurement cycles to be carried out.

Can data be accessed remotely?
Yes, via Wi-Fi the instrument can send data to an FTP server. Data can also be exported in PDF and CSV format using DeltaLog10 software.

What is the purpose of the built-in camera?
The camera allows images of the monitored environment to be stored. This helps link the measured data to the actual context, such as a workstation, room, system or work area.

Is the instrument compliant with ISO standards for microclimate assessment?
Yes, it complies with the main reference standards for comfort and thermal stress assessment, including ISO 7726, ISO 7730, ISO 7243, ISO 9886, ISO 8996 and ISO 11079.

Can it estimate SARS-CoV-2 decay on surfaces?
Yes, the instrument can estimate the natural decay time of SARS-CoV-2 on surfaces based on ambient temperature and relative humidity, according to the equation indicated in the technical documentation.