API Documentation Status

The simple API to quantify human heat balance with one set of inputs in multiple validated models.

API Request

In order to access the API, you must first register for an API Key and then perform a GET request with the following structure:

      
        $ https://www.humanheat.exchange/api/get.php?models={$MODELS}&{$PARAMS}&api_key=API-KEY

Possible Parameters

Below is a table listing all accepted parameters by the API alongside their name and valid value structure. Here is an example API request url for the UTCI (Unversal Thermal Climate Index) model: 

  
    $ https://www.humanheat.exchange/api/get.php?models=UTCI&Tair=30&Trad=40&RH=30&Vair=2&api_key=API-KEY

Note: provides additional info on the parameter.

Parameter Unit Syntax Value Type SSTA PHS HSDA UTCI WBGT PMV TNZ
Person
Weight kg weight= number
Height meters height= number
Age years age= number
Gender N/A gender= 0 = male or 1 = female
Body Surface Area Equation N/A bsacalc= duBois, mosteller
Basal Metabolic Rate N/A bmrmet= rosa, harris, miflin, fixed
Acclimation status N/A acclim= 0 = no or 100 = yes
Days of heat acclimation Days dih= number
Excess Load kg load= number
Skin Temperature °C Tsk= number
Maximum Sweat Rate g/h SRmax= number
Posture N/A posture= 0 = seat, 1 = crouch, 2 = stand
Rehydration N/A drink= number
% Dehydration % dhyd= percent
Clothing
Intrinsic clothing insulation clo icl= number
Evaporative clothing resistance m²/K/W recl= number
Clothing Area Coverage 0-1.0 clo_saf= number
Clothing Emissivity 0-1.0 clo_emi= number
Static clothing permeability index 0-1.0 imst= number
Environment
Ambient Temperature °C Tair= number
Mean Radiant Temperature °C Trad= number
Black Globe Temperature °C Tglobe= number
Ambient Humidity % RH= percent
Air Velocity m/s Vair= number
Pressure kPa Pair= number
Cloud Coverage % clouds= number
Theta Angle ? theta= number
Latitude ° lat= number
Longitude ° long= number
Time of Day (UTC) string tod= string
Activity
Metabolic Rate W/m² M= number
Metabolic Equivalents MET met= number
External Work W/m² W= number
Movement Speed m/s speed= number
Grade % grade= number
Terrain ND terrain= number
Modality string modality= static, treadmill, static_cycle, free_run, or free_cycle

Supported Models

SSTA: Steady-State Thermal Audit

The steady-state thermal audit (SSTA) conducts a heat balance assessment based on the parameters provided.

.../api/get.php?models=SSTA&... Interactive Example

Required Parameters:
Item
Value
Description
Value type
Weight (kg)
number
Height (meters)
number
Body Surface Area Equation (N/A)
duBois, mosteller
Acclimation status (N/A)
0 = no or 100 = yes
Skin Temperature (°C)
number
Maximum Sweat Rate (g/h)
number
Posture (N/A)
0 = seat, 1 = crouch, 2 = stand
Intrinsic clothing insulation (clo)
number
Evaporative clothing resistance (m²/K/W)
number
Clothing Area Coverage (0-1.0)
number
Clothing Emissivity (0-1.0)
number
Static clothing permeability index (0-1.0)
number
Ambient Temperature (°C)
number
Mean Radiant Temperature (°C)
number
Ambient Humidity (%)
percent
Air Velocity (m/s)
number
Pressure (kPa)
number
Metabolic Rate (W/m²)
number
Metabolic Equivalents (MET)
number
External Work (W/m²)
number
Movement Speed (m/s)
number
Modality (string)
static, treadmill, static_cycle, free_run, or free_cycle
Register (FREE)
CURL 
            
              $
Request URL 
            
              $
Response: 
$

PHS: Predictive Heat Strain

The Predictive Heat Strain Model (PHS, ISO 7933:2004) is used to evaluate the thermal stress experienced by a subject in a hot environment. The model predicts the maximum allowable exposure times determined from the attainment of a core temperature exceeding 38.5C, or excessive sweating causing dehydration.

.../api/get.php?models=PHS&... Interactive Example

Required Parameters:
Item
Value
Description
Value type
Weight (kg)
number
Height (meters)
number
Acclimation status (N/A)
0 = no or 100 = yes
Posture (N/A)
0 = seat, 1 = crouch, 2 = stand
Rehydration (N/A)
number
Intrinsic clothing insulation (clo)
number
Evaporative clothing resistance (m²/K/W)
number
Clothing Area Coverage (0-1.0)
number
Clothing Emissivity (0-1.0)
number
Static clothing permeability index (0-1.0)
number
Ambient Temperature (°C)
number
Mean Radiant Temperature (°C)
number
Ambient Humidity (%)
percent
Air Velocity (m/s)
number
Theta Angle (?)
number
Metabolic Rate (W/m²)
number
External Work (W/m²)
number
Movement Speed (m/s)
number
Register (FREE)
CURL 
            
              $
Request URL 
            
              $
Response: 
$

UTCI: Universal Thermal Climate Index

The Universal Thermal Climate Index (UTCI) is a simple assessment of the thermophysiological responses for a standard homiotherm using easily accessible meteorological data. The returning value, a UTCI Equivalent Temperature, can then be assessed against a normative scale to determine the relative heat/cold strain. The UTCI implementation uses the operational procedure as published in the International Journal of Biometeorology. UTCI development was supported by the European Commission via EU COST Action 730.

.../api/get.php?models=UTCI&... Interactive Example

Required Parameters:
Item
Value
Description
Value type
Ambient Temperature (°C)
number
Mean Radiant Temperature (°C)
number
Ambient Humidity (%)
percent
Air Velocity (m/s)
number
Register (FREE)
CURL 
            
              $
Request URL 
            
              $
Response: 
$

WBGT: Wet Bulb Globe Temperature

Wet Bulb Globe Temperature (WBGT) is used by many organizations to evaluate the relative heat strain during exposure to high ambient temperatures.

.../api/get.php?models=WBGT&... Interactive Example

Required Parameters:
Item
Value
Description
Value type
Ambient Temperature (°C)
number
Ambient Humidity (%)
percent
Air Velocity (m/s)
number
Pressure (kPa)
number
Cloud Coverage (%)
number
Latitude (°)
number
Longitude (°)
number
Time of Day (UTC) (string)
string
Register (FREE)
CURL 
            
              $
Request URL 
            
              $
Response: 
$

PMV: Predicted Mean Vote

Thermal sensation is mainly related by the heat balance of an individual with their surrounding environment. ISO 7730 offers a simple method for estimating whole body thermal sensation by considering the environmental conditions (e.g. ambient temperature, humidity) and person (e.g. activity level, clothing) to calculate the Predicted Mean Vote (PMV) and the predicted percentage of dissatisfied (PPD). This estimate is primarily used to assess indoor thermal comfort of workspaces, however it has been employed in outdoor settings. More info on ISO 7730 can be found here.

.../api/get.php?models=PMV&... Interactive Example

Required Parameters:
Item
Value
Description
Value type
Skin Temperature (°C)
number
Intrinsic clothing insulation (clo)
number
Ambient Temperature (°C)
number
Mean Radiant Temperature (°C)
number
Ambient Humidity (%)
percent
Air Velocity (m/s)
number
Metabolic Rate (W/m²)
number
External Work (W/m²)
number
Register (FREE)
CURL 
            
              $
Request URL 
            
              $
Response: 
$

TNZ: Thermoneutral Zone

The Thermoneutral Zone (TNZ) is defined as the range of environmental conditions without physiological regulatory responses to alter metabolic rate or initiate sweating. For a given set of parameters, the range of ambient and skin temperature coinsiding with the thermoneutral zone will be returned.

.../api/get.php?models=TNZ&... Interactive Example

Required Parameters:
Item
Value
Description
Value type
Weight (kg)
number
Height (meters)
number
Age (years)
number
Gender (N/A)
0 = male or 1 = female
Body Surface Area Equation (N/A)
duBois, mosteller
Basal Metabolic Rate (N/A)
rosa, harris, miflin, fixed
Skin Temperature (°C)
number
Intrinsic clothing insulation (clo)
number
Ambient Temperature (°C)
number
Ambient Humidity (%)
percent
Air Velocity (m/s)
number
Metabolic Rate (W/m²)
number
Metabolic Equivalents (MET)
number
Register (FREE)
CURL 
            
              $
Request URL 
            
              $
Response: 
$

HSDA: Heat Strain Decision Aid

The Heat Strain Decision Aid was developed by the U.S. Army Research Institute of Environmental Medicine to predict the core temperature response during marches in protective garments with or without excess load carry. This HSDA model provides the rise in core temperature over 480 minutes of work.

.../api/get.php?models=HSDA&... Interactive Example

Required Parameters:
Item
Value
Description
Value type
Weight (kg)
number
Height (meters)
number
Days of heat acclimation (Days)
number
Excess Load (kg)
number
Skin Temperature (°C)
number
% Dehydration (%)
percent
Intrinsic clothing insulation (clo)
number
Static clothing permeability index (0-1.0)
number
Ambient Temperature (°C)
number
Black Globe Temperature (°C)
number
Ambient Humidity (%)
percent
Air Velocity (m/s)
number
Movement Speed (m/s)
number
Grade (%)
number
Terrain (ND)
number
Register (FREE)
CURL 
            
              $
Request URL 
            
              $
Response: 
$