Lesson 3.4 - Dressing for Heat and Cold

Keeping warm in the winter is very important.  Insulation and reducing heat transfer are the key concepts.  What about the materials used to protect the body from extreme heat or rapid heat loss? 

Read Dressing for Intense Heat - or Cold on pages 124 and 125 in your textbook. As usual, answer the following questions.

Question 1. What are three important features of firefighters' clothing?

Question 2. How do scientists test firefighters' clothing?

Question 3. Where is Harry the mannequin located?  How many sensors does Harry have?

Question 4. Of what are dive suits made?

 

Check your answers with those that follow.

 

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 1. What are three important features of firefighters' clothing?

First, firefighters' clothing must be fireproof.  The clothing must not be able to catch on fire. 

Second, the clothing must be a good insulator and prevent the heat from the fire from transferring to the body of the firefighter. 

Third, the inside material has to absorb moisture.    

Question 2. How do scientists test firefighters' clothing?   

Scientists test firefighters' clothing by putting it on a special mannequin called Harry.  They then expose the mannequin to extreme fire conditions.

Question 3. Where is Harry the mannequin located?  How many sensors does Harry have?

Harry the mannequin is located at the University of Alberta.  Harry has 110 sensors that measure the rate and amount of heat transfer through the firefighters' clothing.

Question 4. Of what are dive suits made?

According to the text, dive suits are made of neoprene that has tiny bubbles of air in it.  There are two types of neoprene dive suits, wet and dry. 

Wet suits allow water to soak through to the skin of the diver, something like a sponge.  The body heat of the diver warms the layer of water next to the skin and the neoprene prevents this warm water from escaping.  Wet suits are used in shallower depths and relatively warmer water. 

Dry suits are also made of neoprene but they are made so that water cannot penetrate at all.  The diver wears an insulated suit underneath the dry suit to keep warm.  Dry suits are used in deeper depths and colder water. 

 


Now, do Assignment 6C.  Page forward to access the computer-scored assignment.