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HHA Press release -June
1995
Wood Heaters Hold Key To Improved Air Quality
Like other areas throughout the world, Christchurch suffers from
temperature inversions in winter which cause a smog-like atmosphere,
resulting in poor air quality throughout the district.
Car exhausts, industry, commercial use and heating all contribute
to this effect to a greater or lesser degree, but some industry
experts say domestic wood heating has received more than its
fair share of the blame.
Dave Pullen, President of the New Zealand Home Heating Association,
says this is because all solid fuels, and appliances, are lumped
together with open fires when addressing the issue of air quality.
"We readily accept the need to improve the situation
in Christchurch and other areas. It has been one of the Association's
key mandates for many years now. As a trade body we have been
instrumental in developing international emissions codes for
wood burning appliances."
Recent developments in wood heater design have resulted
in emissions levels not thought achievable 10 years ago, and
most appliances now produce a clean and environmentally acceptable
burn, even when not operated correctly.
In addition to the familiar enclosed wood heater, specially
designed high efficiency fireplace inserts burn almost as cleanly,
yet provide the ambience and accessibility of an open fire.
The reality, it is claimed, is that in the air quality
equation, wood heating is not the demon it seems.
Open fires in masonry chimneys appear to be the X factor
- the unknown quantity.
While emission levels from wood burning appliances are
measurable, little has been done to effectively assess pollution
from the ordinary open fire.
"An estimated 45 000 open fires are still in regular use
in the Christchurch area during the winter period," said
Mr Pullen." And it is quite probable that more than 50%
use coal as their main fuel."
The real problem appears to be that no meaningful qualitative
or quantitative research on the affect of open fires, and user
habits, has yet been undertaken.
Because of design and low operating temperatures, there
can be no control on the level of particulate matter emitted
from the traditional open fire, even if only wood is burnt. But
the situation becomes worse with coal.
"We know that open fires in masonry chimneys are extremely
"dirty" by comparison to wood heaters, and we are not
convinced that sufficient research has been done to ascertain
their true impact on air quality" he continued.
Yet imposing controls on the open fire is difficult because so
much relies on the integrity of the operator.
He says that properly conducted tests may well confirm
the Association's assertion that by simply replacing 25% of existing
open fires with inbuilt wood burners, or high efficiency wood
burning fireplace inserts, could reduce Christchurch' s emissions
levels by as much as 1.5 tonnes in just a 4 hour period on a
cold night.
"While this figure has been derived from a number of different
tests done by various laboratories, we believe a reduction of
this magnitude could be realistic. Controlled research into this
area is absolutely vital if Christchurch is to make significant
advancements in reducing pollution attributed to solid fuel home
heating" he said.
In calling for this research, Mr. Pullen said that there was
good reason to believe that by introducing an incentive to convert
fireplaces to wood heaters, combined with a public education
programme, a substantial improvement in air quality would result.
"In Launceston, which suffers similar atmospheric conditions,
a targeted education programme produced a substantial positive
outcome in a very short space of time " he said.
"If such a programme was introduced here, we would see similar
results. Combine this with a heater or insert replacement programme,
and we believe that the outcome would be quite startling."
he concluded.
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