ARCHIVE FEATURE
Boom time for farmers
An innovative bit of UK agricultural engineering helped address
growing concerns over the impact of pesticide crop spraying
Farmers want the maximum yields from their crops
and the tools to help them achieve this are numerous,
evolving and sometimes controversial.
Among them are pesticides, which were becoming
widespread in a post-war economy that continued
food rationing until 1953.
Since their introduction, however, pesticides have
been linked with a decline in biodiversity, notably bee
populations; for having negative impacts on air, soil and
water, and for being detrimental to human health.
Less than a decade after the war, it was becoming clear
that pesticides had to be applied in a more controlled
and targeted manner due to the damage caused by weed
killers and insecticides drifting away from their intended
target and causing damage to diff erent crops nearby.
The Ministry of Agriculture also raised concerns about
protections aff orded to agricultural workers who were
applying these chemicals.
Current regulations from the Health and Safety
Executive state: ‘Users of pesticides must ensure that
all reasonable precautions are taken to prevent spray
drift. Reasonable precautions include using the right
spraying techniques and equipment, taking account of
weather conditions and the need to protect neighbours’
interests and other members of the public, wildlife and the
environment.’
Pest Control Ltd, from Harston, Cambridgeshire, were
among the fi rst to pay close a ention to the problem
of drift in crop spraying and in April 1951 The Engineer
reported on fi eld trials of ‘Nodrif’, an engineered solution
to the problem.
Led by managing director Dr WE Ripper, the Nodrif
boom was employed on the company’s standard
‘Cambridge’ sprayers which had a spray bar 40ft wide and
an arrangement that enabled the height of the spray bar to
be accurately adjusted.
“The spray bar consists of three sections, each of which
has its individual cowl,” said The Engineer. “Both the side
April 2020 / www.theengineer.co.uk
526
booms are supported by castor wheels, which keep the
spray bar at a constant distance from the ground and also
to prevent the wind shields from digging into the ground.
The wind shields themselves are arranged to form a large
obtuse angle with the fi eld, so that the wind may be more
easily defl ected over them. To guard against side winds,
folding triangular defl ectors have been provided and there
is a serrated rubber curtain along the lower edges of the
defl ectors, which is an additional aid in preventing wind
from ge ing underneath the shield.”
According to the company’s test results 63 to 100 per
cent of the spray drift could be prevented by the Nodrif
boom. Furthermore, at a wind velocity above 12mph, 18 to
28 per cent of the spray was blown away when ordinary
spray booms were used.
Pest Control’s solution also paid a ention to protecting
the workers applying toxic sprays. In 1950, a working
party set up by the Ministry of Agriculture was invited
to make recommendations for the promotion of the
safety of workers using toxic substances in agriculture.
By 1951 the group had put forward suggestions that
included protective clothing and arrangements for
decontamination.
use of its Nodrif boom ‘as it helps to ensure that operators
are not smothered by the chemical when spraying
operations in wind are carried out.’
“But the fi rm has also made improvements in the
gasproof air-conditioned tractor cabs which it produces for
its contracting plant,” said The Engineer. “The improved
cab…is an almost air-tight cabin, into which air is passed
through a compressor driven from the power take-off of
the tractor. On the intake side of the compressor there is a
large charcoal fi lter which absorbs gases and in front of it
is a fi lter for collecting fi ne smoke and dusts.
“A pressure, rather higher than the atmospheric
pressure, is maintained, and the air escapes through
the gaps in the cab structure through which the tractor
april 1951
Pest Control said additional protection was given by the
written by JASON FORD
April 1951– Crop spraying
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