Xref: utzoo tor.general:1257 ont.general:1097 can.general:2098
Newsgroups: tor.general,ont.general,can.general
Path: utzoo!lsuc!tmsoft!ead
From: ead@tmsoft.uucp (Elizabeth Doucette)
Subject: Re: Air Pollution Index - Air Quality
Message-ID: <1989Nov11.073016.27360@tmsoft.uucp>
Organization: EAD MoneyHealth Inc, Toronto, Canada
References: <1989Nov6.034902.11119@tmsoft.uucp> <31081@watmath.waterloo.edu>
Date: Sat, 11 Nov 89 07:30:16 GMT
<1989Nov9.110604.6154@contact.uucp>
Reply-To: ead@tmsoft.UUCP (Elizabeth Doucette)
Followup-To: tor.general
Distribution: can
Organization: EAD MoneyHealth Inc, Toronto, Canada

In article <1989Nov9.110604.6154@contact.uucp> eisen@contact.UUCP
(Martin Loeffler) writes:
> Just what do the index levels represent?

This information is from Dr. Rob Blozum at the Ministry of the
Environment. 

There are six chemicals, or group of chemicals, that are monitored for
the Air Quality Index (AQI).  Each chemical has it's own AQI
calculated.  The AQI is related to appropriate concentrations of the
chemical and the different risks to people. 

** The AQI is calculated for each of the six chemicals or group of
chemicals listed below.  The AQI that is published by the Ministry of
the Environment for the public, is the highest of these six AQI
numbers. 
 
SO2
---
* smelters (i.e. INCO, Falconbridge, Thompson)
* power plants burning coal
* steel industry burning coal (coke) (Algoma Steel)
* refining oil
* gasoline in cars, diesels

AQI      ppb#         # part per billion
---      ----
 15       170
 32       250
 50       340
100      2000

AQI  0-14 very good
    15-31 good
    32-49 moderate
    50-99 poor  
 
O3
--
                       photochemical
* NOx + hydrocarbons  ---------------> O3
                         reaction
* O3 is highest in the summer months

AQI      ppb
---      ----
 15       50
 32       80
 50      120
100      200

 
CO
--
* almost 100% from cars
* methane ---> CO

one hour average
----------------
AQI      ppm#         # part per million
---      ----
 15       12
 32       23
 50       30
100       50

eight hour average
------------------
AQI      ppm
---      ----
 15        5
 32       10
 50       14
100       18
 
NO2 (NOx)
---------
* cars, diesels, 60%
* coal fired power plants
 
AQI      ppb
---      ---
 15      120
 32      200
 50      260
100      530

particulates
------------
* SO2  ---> SO4 forms particulates
* nitrate particulates
* road dust
* car emissions
* industrial sources  ---> stacks
                           piled up tailings
* construction industry
* stagnant fog makes particulate readings high because of
  poor mixing (convective) environmental conditions
* particulates tend to be higher in the morning
 
AQI      CHU#         # Coefficient of Haze Units
---      ----
 15       1
 32       2
 50       4
 70       5
100       7

Coefficient of haze units is used instead of grams per cubic metre.
The latter is used when the sample has been collected on filter paper
over 24 hours and then analysed.  For CHU, the light attenuation of
the particles on filter paper is measured.  There is a direct
correlation between the two methods.  Each monitoring site has its
own CHUs because of the type of particulate matter. 
 
total reduced sulphur (TRS)
---------------------------
* H2S and other odour causing compounds, i.e. mercaptans
* Cornwall and Windsor tend to be high in TRS
* steel mills, pulp & paper mills
 
AQI      ppb
---      ----
 15         5
 32        10
 50        27
100      1000#        # nose is saturated
 

Elizabeth