A huge legal responsibility lies on those responsible for
cleaning up industrial dusts and other materials within
manufacturing processes. Here Nilfisk-CFM looks at the
legal requirements and some of the solutions available

Failure to comply with current
standards can lead to loss of life,
serious injury and extensive damage to
property. Heavy fines can be levied against
companies who put their employees at risk by
failing to carry out adequate risk assessments.

Modern industry deals with a wide range of
materials in a variety of working conditions.

Some of these materials in dust form are
known to be hazardous to health; others may
not be thought of as a health hazard but
could, in certain circumstances, prove lethal
if cleaned up using the wrong equipment.

Some cleaning machines may have to work in
hazardous areas caused by the presence of
flammable vapours or gases.

Could my vacuum cleaner explode?
If the material being collected is combustible
it will be mixed with large amounts of air
within the vacuum cleaner. This will form a
cloud of dust and vapours inside the
machine. All that is then required to produce
an explosion is an ignition source. Vacuum
cleaners produce static electricity as the dust
passes through the machine. Conventional
vacuum cleaner motors also produce sparks
from carbon brushes. The elements needed to
produce an explosion are present, so an
incident could result.

These risks have long been recognised and
technical solutions found which remove the
risk of ignition. Machines for combustible
dusts are constructed so that static electricity
is safely routed to earth and the motors used
do not create sparks. Additional standards
apply to machines that are required to work
in atmospheres which are hazardous due to
the presence of flammable gases or vapours.

The employer has legal duties under the
ATEX 137 Directive to conduct a risk analysis
on their processes (which includes cleaning)
and to then select ATEX approved equipment
intended for use in high risk areas. The
employer also has duties under the
Dangerous Substances and Explosive
Atmospheres Regulations 2002 that
specifically include implementing control
measures and providing equipment which
will reduce the quantity of dangerous dusts
and prevent explosive atmospheres.

Nilfisk-CFM has developed Safety Vacuum
Cleaners that are designed for the collection
of combustible dusts. These vacuum cleaners
are submitted to specially Notified Bodies for
testing and ATEX certification for equipment
within potentially explosive atmospheres. The
ATEX approval will be specific to the
category of equipment and nature of the risk.

Hazardous places are classified in zones on
the basis of the frequency and duration of the
occurrence of an explosive atmosphere. For
gases, vapours and mists the zones are:
Zone 0 – A place in which an explosive
atmosphere consisting of a mixture with air
of dangerous substances in the form of gas,
vapour or mist is present continuously or for
long periods
Zone 1 – A place in which an explosive
atmosphere consisting of a mixture with air
of dangerous substances in the form of gas,
vapour or mist is likely to occur in normal
operation occasionally.

Zone 2 – A place in which an explosive
atmosphere consisting of a mixture with air
of dangerous substances in the form of gas,
vapour or mist is not likely to occur in
normal operation but, if it does occur, will
persist for a short period only.

For dusts the zone classifications are:
Zone 20 – A place in which an explosive
atmosphere in the form of a cloud of
combustible dust in air is present
continuously, or for frequent long periods.

Zone 21 – A place in which an explosive
atmosphere in the form of a cloud of
combustible dust in air is likely to occur in
normal operation occasionally.

Zone 22 – A place in which an explosive
atmosphere in the form of a cloud of
combustible dust in air is not likely to occur
in normal operation but, if it does occur, will
persist for a short period only.