Read the following passage.
A. On June 7, 2023, the Air Quality Health Index in Ottawa reached 10+, the top of its scale. The amount of fine particulate matter in the air there hit 511, when it normally ranges from 4 to 11. The smoke came largely from fires burning across Nova Scotia, Quebec and northeastern Ontario. On several days that month a yellow-tinted haze also settled over Toronto, and the smoke was thick enough that airports had to pause or slow air traffic because of poor visibility.
B. Wildfire smoke is a mix of gases, particles and water vapour. Its fine particles, known as PM2.5, are too small to see and carry the main health risk, and for some of the pollutants in smoke there is no known safe level of exposure. Smoke can be carried thousands of kilometres from the fire zone, so the air may be poor even where people cannot see or smell it. Those most at risk include people with lung or heart conditions and people who work outdoors, such as wildland firefighters. Wildfire season usually runs from early April to October.
C. Communities respond in practical ways. In May 2023, smoke pushed the index to 10+ across much of Alberta, and Edmonton launched its first extreme weather response to poor air quality: schools held recess indoors and cancelled outdoor excursions. When another wave of smoke reached Ottawa on June 25, the city closed outdoor pools and called off its outdoor recreation programs. At home, Health Canada advises keeping windows and doors closed and using the best filter a ventilation system can handle or a certified portable air cleaner. Clogged filters do not remove smoke well, so they should be changed regularly.
D. Environment and Climate Change Canada reports the Air Quality Health Index (AQHI), a scale from 1 to 10+, in many locations, and it issues air quality alerts in communities affected by wildfire smoke. The alerts are colour-coded yellow, orange or red, and the index helps the agency choose the colour. During a smoke event, the formula is adjusted to use only fine particles, calculated every hour, so that health risks can be judged more accurately. The advice that comes with the index and alerts may include changing outdoor activities or travel plans. Most of Canada has used the AQHI since June 24, 2007, when it replaced the older Air Quality Index.
E. Not given in any of the above paragraphs.
Decide which paragraph, A to D, has the information given in each statement below. Select E if the information is not given in any of the paragraphs.
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Correct Answer: B
Why this is correct: The second paragraph says that for some of the pollutants in smoke there is no known safe level of exposure. Pollutants are harmful substances, and no known safe level means no amount is known to be harmless.
Passage Reference: Its fine particles, known as PM2.5, are too small to see and carry the main health risk, and for some of the pollutants in smoke there is no known safe level of exposure.
Tips: The statement says no amount is 'harmless'. Look for a sentence saying experts cannot name any amount that is okay to breathe.
Why the other options are wrong:
- A: The first paragraph gives very high readings in Ottawa on one day, but it says nothing about a safe level of exposure.
- C: Paragraph C is about what schools, the city and households did. It does not discuss safe levels.
- D: Notice that paragraph D explains how the index and alerts work, not whether any amount of a pollutant is safe.
- E: The lack of a known safe level for some smoke pollutants is stated in Paragraph B.
Correct Answer: D
Passage Reference: During a smoke event, the formula is adjusted to use only fine particles, calculated every hour, so that health risks can be judged more accurately.
Why this is correct: The fourth paragraph says that during a smoke event the formula is adjusted to use only fine particles. Using only fine particles means one kind of pollution is used to work out the index.
Tips: Several places talk about the index. Ask which one says how it is worked out during smoke events.
Why the other options are wrong:
- A: Paragraph A reports a fine particle reading in Ottawa, but it does not say how the index is calculated.
- B: Fine particles are described in Paragraph B as the main health risk, but the paragraph says nothing about a formula.
- C: The index reaching 10+ in Alberta comes up in paragraph C, but not how the number is worked out.
- E: The change to the formula during a smoke event, using only fine particles, is in Paragraph D.
Correct Answer: A
Passage Reference: On several days that month a yellow-tinted haze also settled over Toronto, and the smoke was thick enough that airports had to pause or slow air traffic because of poor visibility.
Why this is correct: The first paragraph says the smoke over Toronto was thick. Airports had to pause or slow air traffic because of poor visibility. Held up flights are paused or slowed air traffic, and poor visibility means it was hard to see.
Tips: The fourth paragraph mentions travel plans. Ask which paragraph reports flights actually being held up.
Why the other options are wrong:
- B: Notice that paragraph B says smoke may be hard to see or smell, which is about health, not about flights.
- C: The third paragraph lists cancelled school trips and closed pools, but no delays to air travel.
- D: Travel plans come up in paragraph D as part of the advice with the index. But no flights are said to have been delayed.
- E: Airports pausing or slowing air traffic because of poor visibility are described in Paragraph A.
Correct Answer: B
Passage Reference: Smoke can be carried thousands of kilometres from the fire zone, so the air may be poor even where people cannot see or smell it.
Why this is correct: Look at paragraph B: it says smoke can be carried thousands of kilometres from the fire zone. Thousands of kilometres is more than a thousand, so smoke can drift that far from its fire.
Tips: One paragraph gives a single example of smoke far from home. Another gives the general rule with a distance. Choose the rule.
Why the other options are wrong:
- A: The first paragraph names the regions where the fires burned and where smoke settled, but it gives no distance the smoke travelled.
- C: Notice that paragraph C describes responses in Edmonton and Ottawa. It does not say how far smoke goes.
- D: The fourth paragraph covers the index and alerts. Distance from the fire is not discussed.
- E: The fact that smoke can travel thousands of kilometres is given in Paragraph B.
Correct Answer: C
Passage Reference: In May 2023, smoke pushed the index to 10+ across much of Alberta, and Edmonton launched its first extreme weather response to poor air quality: schools held recess indoors and cancelled outdoor excursions.
Why this is correct: Notice that paragraph C says that during the smoke in May 2023, schools in Edmonton held recess indoors. Holding recess indoors means children spent their school break inside.
Tips: Start with the 'one place in Alberta'. Ask what it changed for children at school, and whether the change was about their breaks.
Why the other options are wrong:
- A: Look at paragraph A: it reports readings in Ottawa and flights in Toronto. Schools are not mentioned.
- B: People who work outdoors are named in Paragraph B as a group at risk, but children at school are not discussed.
- D: Notice that paragraph D says advice may include changing outdoor activities, but it does not mention any school.
- E: Edmonton schools holding recess indoors are reported in Paragraph C.
Correct Answer: E
Passage Reference: The amount of fine particulate matter in the air there hit 511, when it normally ranges from 4 to 11.
Why this is correct: Look at paragraph A: it gives Ottawa's index of 10+ and its fine particle reading on June 7, 2023. It does not compare Ottawa with any other place, so a world ranking is not in the passage.
Tips: A very high number is not the same as the highest in the world.
Why the other options are wrong:
- A: The first paragraph compares Ottawa's reading with its own normal range, not with other places in the world.
- B: Look at paragraph B: it describes smoke in general and who is at risk. It ranks no place.
- C: A second wave of smoke in Ottawa appears in Paragraph C, but again with no comparison to the rest of the world.
- D: The fourth paragraph explains the national index and alerts. It gives no ranking of cities.
Correct Answer: D
Passage Reference: Most of Canada has used the AQHI since June 24, 2007, when it replaced the older Air Quality Index.
Why this is correct: The fourth paragraph says most of Canada has used the AQHI since June 24, 2007. That is when it replaced the older Air Quality Index.
Tips: The index is named in several paragraphs. Look for the year it started.
Why the other options are wrong:
- A: The Air Quality Health Index is named in Paragraph A, but only for a reading in 2023, not its history.
- B: Notice that paragraph B explains what smoke is made of and when fire season runs. No index is introduced there.
- C: The third paragraph mentions the index during the 2023 smoke, but not when it began or what it replaced.
- E: The start of the AQHI in 2007, replacing the older index, is reported in Paragraph D.
Correct Answer: E
Passage Reference: The alerts are colour-coded yellow, orange or red, and the index helps the agency choose the colour.
Why this is correct: Look at paragraph D: it says alerts are colour-coded yellow, orange or red and that the index helps choose the colour. It never says which index number leads to which colour.
Tips: Look at paragraph D: it names the colours. Check whether it gives a number for orange.
Why the other options are wrong:
- A: Look at paragraph A: it gives an index of 10+ for Ottawa, but it does not mention alert colours.
- B: What smoke is made of and who is at risk are the topics of paragraph B. Alerts are not discussed.
- C: The third paragraph reports how Edmonton and Ottawa responded, with no link between colours and numbers.
- D: The fourth paragraph names the three alert colours, but it does not give the index level for any of them.
Correct Answer: A
Passage Reference: The amount of fine particulate matter in the air there hit 511, when it normally ranges from 4 to 11.
Why this is correct: The first paragraph gives the reading for June 7. The amount of fine particulate matter in Ottawa's air hit 511, when it normally ranges from 4 to 11. That is far above the usual level.
Tips: Find the paragraph with real numbers for Ottawa's air.
Why the other options are wrong:
- B: Notice that paragraph B explains that fine particles are the main health risk, but it gives no reading for any place.
- C: Ottawa appears in Paragraph C for a later wave of smoke, but no particle numbers are given there.
- D: Notice that paragraph D says the index uses only fine particles during smoke, not how high they rose in Ottawa.
- E: Ottawa's reading of 511 against a normal range of 4 to 11 is in Paragraph A.
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