Ozone layer is a protective layer which covers earth as a ring or as a blanket which prevent falling of harmful rays from sun to earth. The ozone layer is in stratosphere and some part in troposphere of earth’s atmosphere. The ozone layer is thick at equator region where as thin at above and below equator and very thin at poles.

 

 

 

http://www.acer-acre.ca/stratospheric-ozone-depletion

ozone depleting substances:

                Canada is above the equator so the ozone is thinner. Ozone is depleting due to atmospheric pollution than are done by human beings i.e., mostly by chemical gas pollution which are released form chemical industries , chemicals released from household products like refrigerators ,cleaning sprays air conditioners ,the gases released from the vehicles and the pesticide used for agriculture.. This kind of chemicals which cause depletion of Ozone are called as the ‘ODS’(Ozone depleting substance) for example chloro fluoro carbons, hydro chloro fluoro carbons, carbon tetrachloride …etc. among these chlorofluro carbons are more dangerous and most abundantly released.

http://education.rec.org/bg/ozone_depletion/ozone_depleting_substances/index.shtml

 If you see the mechanism of Ozone depletion the chlorine or any halogen from the ozone depleting substance will react continuously with large amount of Ozone molecules and convert it in to oxygen. For better understand one atom of fluorine can convert 100,000 molecules of ozone to oxygen.

And the carbon monoxide released from the cars will react with the atmospheric nitrous oxide and convert in to the harmful intermediate compound and this compound will react with the Ozone and convert in to oxygen .

Preventive steps:

1.       limit private vehicle using ;

In developed countries like Canada  people are using  private vehicles beyond the necessity . the best thing to do avoid too much using  private vehicles and use public transport.

2.       Use ecofriendly house hold products:

In cold countries like Canada ,in winters there is no necessary to use refrigerators and its better to use fresh food items instead of using stored one.

3.       Avoid using artificial pesticides.

 

Reference:

1.       Retrieved March 25, 2014, from http://1. ec.gc.ca/ozone/default.asp?lang=En&n=2ED3F6DA-1

2.       Retrieved March 25, 2014, from http://1. www.greendiary.com/5-ways-prevent-ozone-depletion.html