Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!


Human physiology, air quality and comfort temperatures, activity and metabolic rates, health effects of carbon monoxide and more

Sponsored Links

Age and Physical Growth - Weight and Height

Age and physical growth of boys and girls - age 2 to 18 years

Air Contaminants - Limits

Permissible limits to exposure of various air contaminants

Ammonia - NH3 - Concentration in Air and Health Effects

Ammonia and health symptoms - smell and threat to life.

Blood Sugar Units

Convert between blood sugar units

Body Weight versus Body Height

Ideal body weight versus height

Carbon Dioxide Concentration - Comfort Levels

CO2 acceptance and comfort level

Carbon Dioxide Concentration in Rooms Occupied with People

The carbon dioxide concentration in a room indicates the air quality and the ventilation system efficiency.

Carbon Dioxide Emission from People

Carbon Dioxide emission from persons depends on activity

Carbon Monoxide and Health Effects

Exposure to Carbon Monoxide - CO and health effects.

Clo - Clothing and Thermal Insulation

Clo is used as a measure of clothes thermal insulation

Clothing, Activity and Human Metabolism

Human metabolism at low and high activity with different levels of clothing

Discomfort Index

Based on dry bulb, wet bulb and dew point temperature

Energy in Food

Energy in carbohydrates, fats and proteins

Food-borne Infections and Diseases

Common bacteria and viruses found in food

Force, Power and Human Operated Machines

Maximum force or power available for human operated machines

Gases Dangerous Concentration Levels

Dangerous and tolerable levels of industrial gases

Globe Temperature

Resultant or globe temperature

Heat Discomfort Zones

Heat discomfort and maximum work load

Sponsored Links

Heat Index

Equivalent heat index vs. air temperature and relative humidity - in degrees Fahrenheit and Celsius.

Human Effects when Exposed to Low-Frequency Noise or Vibration

Physiological effects from low-frequency noise or vibrations.

Human Effort Level - Energy and Heart Rates

Human work effort levels, energy expenditure and associated heart rates

Human Heat Gain

Heat gain from persons in air conditioned spaces - in btu/hr.

Human Need of Air

Fresh air is required for respiration and for transport of heat and vapor emitted from the human body

Illuminance - Recommended Light Level

Recommended light levels - illuminance - for some types of working activities


Legionella pneumophila - bacterium that thrives in water supply systems and air conditioning systems - causing the Legionnairs disease

Life Expectancy

Men and Women - age and life expectancy

Maximum Sound Pressure Level in Rooms

Maximum recommended sound pressure levels in rooms like kindergartens, auditoriums, libraries, cinemas and more.

Met - Metabolic Rate

Metabiolic Rate - Met - is often used as a measuring unit for human body heat or power production

Metabolic Heat Gain from Persons

Human metabolic heat gain in air conditioned rooms.

Physiology - Activity and Metabolic Rate

Heat production from the human body at some common activities

Predicted Mean Vote Index (PMV)

PMV index predicts the mean comfort response of a larger group of people

Recommended Relative Humidity

Recommended relative humidity levels

Relative Humidity and Health

Bacteria, viruses, fungi, mites, asthma and optimum range of relative humidity

Required Rest Time

Relaxation requirements to measures of fatigue

Required Space per Person

Recommended minimum room area per person - commonly used values for calculating indoor climate loads.

Sound - Hearing Threshold vs. Age

Shift in hearing threshold for men and women vs. age.

Sound Intensity, Power and Pressure Levels

Introduction to decibel, sound power, intensity and pressure.

Survival Time in Cold Water

Time to exhaustion and death in cold water

Wet Bulb Globe Temperature (WBGT)

The Wet Bulb Globe Temperature can be used to measure the general Heat-Stress index.

Wind Chill Index

Effective Temperature of air in movement.

Sponsored Links

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse!

About the Engineering ToolBox!


We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.


This page can be cited as

  • Engineering ToolBox, (2009). Physiology. [online] Available at: [Accessed Day Mo. Year].

Modify access date.

. .


3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Scientific Online Calculator

Scientific Calculator

11 26

Sponsored Links