Quiz_ The Fernie Arena Loss incident - Graded_ Attempt review
.pdf
keyboard_arrow_up
School
University of Alberta *
*We aren’t endorsed by this school
Course
250
Subject
English
Date
Dec 6, 2023
Type
Pages
4
Uploaded by BrigadierJaguarMaster551
5/14/23, 11:31 AM
Quiz: The Fernie Arena Loss incident - Graded: Attempt review
https://eclass.srv.ualberta.ca/mod/quiz/review.php?attempt=12943138&cmid=7028686
1/4
Dashboard
/
My courses
/
ENGG 404A (LEC X01 Spring 2023)
/
Week 2 - Online Study:
/
Quiz: The Fernie Arena Loss incident - Graded
Started on
Sunday, 14 May 2023, 11:15 AM
State
Finished
Completed on
Sunday, 14 May 2023, 11:27 AM
Time taken
11 mins 55 secs
Marks
9.00/9.00
Grade
100.00
out of 100.00
Question
1
Correct
Mark 2.00 out of 2.00
The refrigeration system at the Fernie Memorial Arena uses two hazardous substances, ammonia and brine. Match two hazardous properties for
each of ammonia and brine.
Ammonia, physical property relating to flammability
Ammonia, physical property relating to a breathing hazard
Brine, physical property relating to skin contact
Brine, physical property relating to corrosion
flammable and explosive gas
toxic gas, noxious gas
skin irritant at neutral pH
corrosive to ferrous metals
Your answer is correct.
Ammonia, the refrigerant, in its pure form is a gas at standard temperature and pressure, and is both a flammable material and a toxic material
that attacks the respiratory tract of a person. Ammonia solution, what one would find in an ammonia household cleanser, is a solution of
ammonia gas in water.
Brine, the heat transfer fluid, is a saturated solution of a salt, typically NaCl, that is corrosive to most metals, especially ferrous metals, and is an
irritant to the skin of a person. Additives in the brine may significantly reduce or increase the pH, thus increasing the corrosivity of the brine.
Technically, the word "flammable" is really not a word. The correct word that indicates a gas can burn is "inflammable"; however, through
everyday usage, "flammable" has taken on the same meaning as "inflammable", much to the chagrin of grammar teachers.
The correct answer is: Ammonia, physical property relating to flammability → flammable and explosive gas, Ammonia, physical property relating
to a breathing hazard → toxic gas, noxious gas, Brine, physical property relating to skin contact → skin irritant at neutral pH, Brine, physical
property relating to corrosion → corrosive to ferrous metals
5/14/23, 11:31 AM
Quiz: The Fernie Arena Loss incident - Graded: Attempt review
https://eclass.srv.ualberta.ca/mod/quiz/review.php?attempt=12943138&cmid=7028686
2/4
Question
2
Correct
Mark 2.00 out of 2.00
According to
The Energy Wheel
, what source of energy was released at the Fernie Arena?
As a helpful hint, the loss of control was: The brine corroded the chiller tubes over the life of the heat exchanger, and caused a pin-hole leak. The
ammonia leaked from the higher-pressure side into the lower-pressure brine side of the heat exchanger (chiller) though the pinhole leak. The
ammonia increased the pressure in the brine-side of the refrigeration system. This over-pressure caused the mechanical component to fail on the
brine-side piping components. This failure caused a release of a mixture of ammonia gas and brine solution.
Note: There are three correct responses, you only need select one.
Select one:
a.
Chemical - Ammonia Toxicity
Ammonia gas was released and
impacted the workers.
b.
Electrical - Exposed electrical conductors on the motor
c.
Mechanical - The compressor disintegrated
d.
Gravitational - Worker tripped on grade-level piping
e.
Pressure - Ammonia Leak
f.
Chemical - Brine Reaction
g.
Chemical - Ammonia Reaction
Your answer is correct.
There are many sources of energy in an ammonia refrigeration system such as operated at the Fernie Arena.
Process description: Ammonia and brine are process fluids used in the refrigeration system at the Fernie arena. Ammonia is used as a refrigerant,
and brine is used as the heat transfer fluid between the refrigerant and the ice surfaces. The ammonia cools or chills the brine, and the brine
freezes the water on the arena surface. Some refrigerant systems use propylene, but not in this facility. Some heat transfer systems use ethylene
glycol solutions (an antifreeze fluid), but not in this facility.
Chemical energy: Ammonia is an inflammable (look it up) explosive gas and could be ignited and burn or explode, is corrosive to some metals
and substances, and reacts readily with some chlorinated substances. Although there are no chemical reactions, there is a phase-change of
ammonia from liquid (in the higher pressure ammonia piping system) to gas (in the lower pressure brine piping system). Brine is a water
solution with an high concentration of salt (NaCl) and trace quantities of corrosion inhibitors;.
Chemical reaction energy: In an ammonia refrigeration system, there are no intended chemical reactions by design. However, these could
happen: ammonia corrodes unprotected components or attacks soft tissues of humans; ammonia could react with other substances especially
any containing chlorine such as bleach, a common cleaning substance in arenas. (Never MIX ammonia and bleach.) Brine with reduced corrosion
inhibitors can corrode metal components in heat exchanger systems.
Pressure energy: The ammonia gas is compressed and liquefied in the refrigeration process, thus building pressure within the ammonia piping
system. The ammonia pressure typically runs higher than the pressure in the brine system.
Electrical and Mechanical: The electrical energy powering the power that drives the compressor, and the mechanical energy in the spinning
motor and compressor.
There are three correct choices: Depending on how it is defined and context, three sources of energy can be named: ammonia chemical energy
(but NOT chemical reaction energy), pressure (pressurised) energy, and brine reaction energy as explained in the feedback for each of the
choices.
Mechanical potential is the set or assembly of moving parts of the rotating equipment.
The correct answers are: Chemical - Ammonia Toxicity, Pressure - Ammonia Leak, Chemical - Brine Reaction
cross out
cross out
cross out
cross out
cross out
cross out
cross out
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help