Unit D Lesson D15 Designing With Safety in Mind
Completion requirements
Lesson D15: Design for Safety
Video Lesson
People can be injured if structures are designed without consideration for safety. Watch this video to learn more about designing safe structures.
Lesson D15: Design for Safety
Figure D.4.15.1 – A person likely will hit his or her head during a bike accident.
Figure D.4.15.2 – Bike helmets protect the head from injury.
Safety Laws
In Alberta, the law requires that all bicycle riders under the age of 18 wear helmets. Adults should wear bike helmets, too. A bike helmet protects from brain injuries if riders fall from their bikes. Bike helmets are built of hard plastic and lightweight foam. Instead of the skull, these materials take the force in a crash.
In Alberta, the law requires that all bicycle riders under the age of 18 wear helmets. Adults should wear bike helmets, too. A bike helmet protects from brain injuries if riders fall from their bikes. Bike helmets are built of hard plastic and lightweight foam. Instead of the skull, these materials take the force in a crash.
Obviously, considering the benefits of bike helmet safety engineering, adults should wear bike helmets, too. In fact, some provinces require all ages to wear bike helmets.
However, some adults refuse to wear bike helmets for various reasons. Some complain the helmets are uncomfortable while others do not like the effect of helmets on their hair. Where do you stand on this issue? Do you think it should be the law that adults must wear bike helmets?
However, some adults refuse to wear bike helmets for various reasons. Some complain the helmets are uncomfortable while others do not like the effect of helmets on their hair. Where do you stand on this issue? Do you think it should be the law that adults must wear bike helmets?
Reading and Materials for This Lesson
Science in Action 7
Materials:
Science in Action 7
Reading: Pages 324–328
Materials:
dry spaghetti, miniature marshmallows, measuring tape or metre stick, hard-boiled egg, raw egg
Watch More
Bike Helmet Testing
Before being sold in stores, bike helmets must be tested for safety. This video shows how bike helmets are tested as well as some instructions on how to fit a bike helmet correctly.
Before being sold in stores, bike helmets must be tested for safety. This video shows how bike helmets are tested as well as some instructions on how to fit a bike helmet correctly.
Many people do not like to wear bike helmets because they dislike the look of helmets or because they consider helmets uncomfortable. This video explains a new design from Sweden for an invisible bike helmet!
Figure D.4.15.4 – A day at the fair is more fun on a ride!
Figure D.4.15.5 – Amusement park rides are fun activities.
Amusement Park Safety
Many people like exciting amusement park rides. Rides are thrilling because they feel dangerous while they actually are very safe.
Roller coasters are a strong frame structure with lots of load-supporting triangles. Roller coasters from 100 years ago were made of wood.
Most roller coasters today are constructed from stiff hollow steel tubes. Careful speed calculations and safety features are incorporated into roller coasters so that people do not fall off during the ride.
Figure D.4.15.8 – Locking harnesses and lap bars are safety features designed to make roller coasters safe.
Figure D.4.15.6 – In the past, the frame of roller coasters were built of wood.
Figure D.4.15.7 – Modern roller coasters are made of steel.
Watch More
Roller Coaster Safety
This video explains how engineers inspect and test roller coasters for safety.
This video explains how engineers inspect and test roller coasters for safety.
Figure D.4.15.9 – A luge track is built for both speed and safety.
Figure D.4.15.10 – Luge racers require control the movement of their sleds with their body weight.
Designing Safer Luge Tracks
Luge is a Winter Olympic sport in which racers lie on their backs on a sled and zip down an ice track feet-first at speeds of nearly 150 km/h. The racer steers the sled by shifting body weight. Luge sleds have no brakes. This means that the luge track must be designed to keep the sleds and the racers on the track.
During a practice run for the 2010 Winter Olympics in Vancouver, a luge athlete lost control, flew off the luge track, and died. This news report explains concerns with the luge track safety.
After this sad event, luge track designers for the 2014 Winter Olympics in Sochi, Russia, deliberately included some uphill sections in the track to slow the racers.
Luge is a Winter Olympic sport in which racers lie on their backs on a sled and zip down an ice track feet-first at speeds of nearly 150 km/h. The racer steers the sled by shifting body weight. Luge sleds have no brakes. This means that the luge track must be designed to keep the sleds and the racers on the track.
During a practice run for the 2010 Winter Olympics in Vancouver, a luge athlete lost control, flew off the luge track, and died. This news report explains concerns with the luge track safety.
After this sad event, luge track designers for the 2014 Winter Olympics in Sochi, Russia, deliberately included some uphill sections in the track to slow the racers.
Watch More
This video shows how the luge track in Sochi was designed to be safer than the luge track in Vancouver was.
An Olympic luge racer strapped a video camera to his helmet to show what it was like to go down the luge track in Sochi. You can watch his video here.
Figure D.4.15.11 – Fires such as the Toronto fire can cause structures to be destroyed completely.
Figure D.4.15.12 – The 1904 Toronto fire destroyed several city blocks.
Buildings and Fire Safety
At various times in history huge fires occurred in cities. You may have heard of the Great Fire of London in 1666 or the Chicago Fire of 1871. In Toronto, Ontario, in 1904, a huge fire destroyed 104 buildings.
These horrible fires caused governments to develop and improve building codes, which are rules for constructing safe buildings. Engineers, architects, and construction workers must follow building codes when they design and construct buildings.
No building is completely fireproof. Even steel loses its strength and buckles at very high temperatures. Modern building codes include many fire safety features designed to contain a fire long enough for people to leave the building safely. Fire safety design in buildings includes sprinkler systems, fire alarms, wide hallways and stairs, and heavy doors.
At various times in history huge fires occurred in cities. You may have heard of the Great Fire of London in 1666 or the Chicago Fire of 1871. In Toronto, Ontario, in 1904, a huge fire destroyed 104 buildings.
These horrible fires caused governments to develop and improve building codes, which are rules for constructing safe buildings. Engineers, architects, and construction workers must follow building codes when they design and construct buildings.
No building is completely fireproof. Even steel loses its strength and buckles at very high temperatures. Modern building codes include many fire safety features designed to contain a fire long enough for people to leave the building safely. Fire safety design in buildings includes sprinkler systems, fire alarms, wide hallways and stairs, and heavy doors.
Figure D.4.15.13 – Fires in buildings are destructive and dangerous.
Figure D.4.15.14 – Heavy doors block stairwells from spreading fire, but allow people to exit safely.
Figure D.4.15.15 – When heated by a fire, sprinkler systems open and spray water.
Lesson Activity
Safe Structure for an Egg
Use all the knowledge you have about structures and forces to design and build a tall structure that can support an egg safely.
Materials:
- dry spaghetti
- miniature marshmallows
- measuring tape or meter stick
- hard-boiled egg
- raw egg
Instructions:
-
Design a structure at least 1 metre tall that will support an egg safely at the top. You can use only spaghetti and marshmallows to build the structure. You can design your structure to be taller than 1 metre if you like. You might want to ask yourself
the following questions as you make your design:
- What is the length of one piece of spaghetti?
- Can I break spaghetti easily into exact lengths?
- What do I know about centre of gravity, symmetry, balance, static load, dynamic load, and stable shapes that I could use in my design?
- How will the egg stay in place at the top?
- Follow your design to build your spaghetti and marshmallow structure.
- Test your structure by placing a hard-boiled egg at the very top.
- If your structure fails, what could you do to improve it? Rebuild the structure with your improvements.
- If you dare, test your final structure with a raw egg!
Make sure you have understood everything in this lesson. Use the Self-Check below, and the Self-Check & Lesson Review Tips to
guide your learning.
Unit D Lesson 15 Self-Check
Instructions
Complete the following 6 steps.
Don't skip steps – if you do them in order, you will confirm your
understanding of this lesson and create a study bank for the future.
- DOWNLOAD the self-check quiz by clicking here.
- ANSWER all the questions on the downloaded quiz in the spaces provided. Think carefully before typing your answers. Review this lesson if you need to. Save your quiz when you are done.
- COMPARE your answers with the suggested "Self-Check Quiz Answers" below. WAIT! You didn't skip step 2, did you? It's very important to carefully write out your own answers before checking the suggested answers.
-
REVISE your quiz answers if you need to. If you answered all the questions correctly, you can skip this step. Revise means to change, fix, and add extra notes if you need to. This quiz is NOT FOR MARKS, so it is perfectly OK to correct
any mistakes you made. This will make your self-check quiz an excellent study tool you can use later.
- SAVE your quiz to a folder on your computer, or to your Private Files. That way you will know where it is for later studying.
- CHECK with your teacher if you need to. If after completing all these steps you are still not sure about the questions or your answers, you should ask for more feedback from your teacher. To do this, post in the Course Questions Forum, or send your teacher an email. In either case, attach your completed quiz and ask; "Can you look at this quiz and give me some feedback please?" They will be happy to help you!
Self-Check Time!
|
Self-Check Quiz Answers
Click each of the suggested answers below, and carefully compare your answers to the suggested answers.
If you have not done the quiz yet – STOP – and go back to step 1 above. Do not look at the answers without first trying the questions.
Seat belts are used to stop people from flying forward and hitting their heads or other passengers during a car collision. Air bags inflate when a car stops suddenly or crashes to prevent people’s heads from hitting the the interior
of the car. The front and back of a car have crumple zones that are designed to absorb the force of a crash.
According to Alberta’s building code, stair treads must be at least 235 mm and no more than 355 mm deep so a person has enough room to place his or her entire foot on each step. Otherwise, a person’ foot could slip off the stair, causing a fall.
Handrails are a safety feature that people can hold for extra balance and stability.
Spacings in railings on a back deck are not more than 10 cm to prevent people, and especially small children, from squeezing through the railings, falling, and hurting themselves.
Schools must have wide hallways and stairwells to provide enough room for large numbers of people to exit the school quickly in case of fire or other emergency.
Wearing a helmet while skiing or snowboarding is a good idea because a person could fall and hit his or her head on hard ground, ice, or a tree. A helmet protects the brain from injury.