Physiological Phase Diagram | Metabolic heat imbalance chart

NET HEAT STATE

Net heat imbalance (W/m²) across the psychrometric plane — metabolic heat production minus all body heat loss pathways — coloured by thermal stress band. Drag the air speed and MRT sliders to explore the 3-D comfort space.

3-D slice controls
Air speed (m/s) 0.10
MRT (°C) 25.0
Radiant environment specification
Radiant environment
Active radiant temp. (°C) 25.0 °C
View factor (%) 50%
Occupant parameters
Metabolic rate (met) 1.2
Skin wettedness 0.06
Heat stress bands (W/m²)
≥ 180 — heat stress
96 – 179 — mild stress
34 – 95 — slightly warm
−57 – 33 — neutral
−119 – −58 — slightly cool
−191 – −120 — cool stress
≤ −192 — cold stress
Cursor
DBT—
HR (g/kg)—
RH—
Imbalance—
Band—

Physiological Phase Diagram — 3D explorer

CUSTOM AXES

Choose any two parameters as chart axes; the remaining parameters become sliders. When dry-bulb temperature and humidity ratio are the axes, psychrometric geometry is applied automatically.

Equate air temperature and MRT — use a single combined temperature slider
Axis selection
X axis
Y axis
X axis selected
Y axis selected
Z axis (3D) selected
select X and Y axes above to render the chart