Metallisation ARC150-2310D, Руководство по эксплуатации

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1.3.3 Fume & Dust
Powdered metals, particularly titanium, aluminium and magnesium give rise to a fire
and explosion risk, depending on the circumstances. Powdered materials can collect in
ducting, on filters, and around the spray booth. If these accumulations are heavy, and they are
disturbed, they can be ignited. An explosion may result from the ignition of a dust cloud,
inside, or outside the equipment. A fire may follow from an explosion and its fireball, or may
result from self-ignition of layers of accumulated dust on hot surfaces, including some
electrical equipment.
Many of the materials that are routinely sprayed have the potential to be hazardous to health
due to their intrinsic properties. Even the least toxic materials, if present in the air in sufficient
quantities, can be hazardous to health. Dust produced by the process produce airborne
particulate matter, in size ranges that can be inhaled. Both inhalable and respirable matter
may be produced. Respirable particles are more dangerous because they can be breathed
deeply into the lungs. The user must therefore identify the hazards, assess the risks, and
prevent or, where not reasonably practicable, adequately control them. The assessment must
take into account all occasions where exposure may occur
– which include spraying, cleaning,
disposal and maintenance.
Several commonly sprayed substances are subject to statutory exposure limits. The
assessment must take into account these exposure limits. When a substance or preparation
has an occupational exposure standard, control of exposure is adequate if levels are
maintained below that standard. Below are the most commonly sprayed materials. However,
other materials may also be toxic. It is essential that users consult the MSDS (Material Safety
Data Sheets) that arrive with their consumables (manufacturers must supply these), so that
they can take into account the health effects, any exposure limits, and any properties such as
explosion hazard, when conducting their risk assessments.
Key Hazards: Fire & explosion, toxic effects by inhalation, toxic effects by skin contact.
The information that follows highlights the most commonly sprayed materials and their
potential effects.
Commonly sprayed materials
Aluminium
Long term inhalation of aluminium powder or aluminium oxide may cause scarring of the
lungs. Aluminium powder can form explosive mixtures with air.
Chromium
Prolonged exposure to Chromium metal dust may give rise to lung fibrosis. It is highly toxic.
Chromium oxide and chrome carbide feedstock are both Chromium (III), the less toxic form of
Chromium. However spraying may convert Chromium (III) compounds to Chromium (IV)
compounds, which are suspected human carcinogens.
Exposure to Chromium (IV)
compounds must be kept as far below the maximum exposure limit (MEL) as is reasonably
practicable.
= May react with water to form hydrogen
= Fire / Explosion Hazard