Light density

Light density decoupling material provides an air space separation between the
pipe or duct and the exterior barrier cladding. This decoupler material is
commonly specified to be light density fiber glass with a minimum of 1” (25 mm)
thickness. Thicknesses greater than 1” offer improved capabilities up to a
practical upper limit of approximately 2” to 3” (50 to 75 mm). The decoupler
material needs to be light and porous as it is the air trapped within the material
which serves the purpose of acoustically separating the wall of the pipe or duct
from the exterior barrier cladding. As an analogy, it is the air space between two
(2) panes of glass which provides the insulation properties of a window. Care
should be taken in the event that a pipe carrying steam or hot water is to be
wrapped to ensure that the temperature insulation capabilities of the decoupler
satisfy the project requirements.

Canopies

Canopies
Design
The canopy hood needs to be designed and operated
to ensure effective removal of cooking fumes. It needs
to be a suitable size and have enough extraction to
minimise fume spillage into the kitchen. There should be
a canopy hood for every appliance and other sources
generating fumes and heat. The canopy hood should
be as close as possible to the source, taking into
account the work requirements.
The airflow into the canopy should be uniform and
constant, and meet the appropriate design flow for the
appliances and room ventilation rate. Canopies and
ductwork need to be constructed from non-combustible
material and made so they discourage accumulations
of dirt or grease, and condensation. There should be
suitable access to the ductwork, to allow regular cleaning
to prevent accumulation of fat etc. Grease filters need to
be readily removable for cleaning/replacement.

Replacement air

Replacement air
The ventilation system design should take into account
the need to replace extracted air. Mechanical and/or
natural means can provide make-up air, but it should
be fresh and unadulterated from the outside.
In smaller kitchens, there may be sufficient
replacement air drawn in naturally via ventilation grilles
in walls, doors or windows.
Where air is drawn in naturally, some means of control
over pest entry is usually needed. A fine mesh grille
will restrict the ventilation, and a larger grille area
can compensate. However, for larger installations, a
mechanical system using a fan and filter is more suitable.
The ‘clean air’ should not be taken from ‘dirty’ areas,
eg waste storage, smoking areas etc. The make-up air
should not impair the performance of flues serving gas
appliances.

Performance

Performance
The extraction rate is best calculated from the
information supplied with the appliances. It should also
take account of air change rates required for kitchens.
Where canopies are not used, eg where extraction is
through ventilated ceilings, consult a competent heating
and ventilation engineer to calculate the appropriate
ventilation rates.
The design should avoid draughts where the kitchen is
subdivided (eg wash-ups, vegetable preparations).
Maintenance
Mechanical ventilation systems should be maintained
in efficient working order in accordance with the
manufacturer’s/installer’s instructions.

what type of specific

what type of specific
equipment you will
need.
In generic terms a
typical equipment
package to inspect,
clean and
decontaminate HVAC
systems will include:
• Vacuum collection
system – puts
ductwork under
negative pressure
(suction).
• Agitation tools –
used to dislodge
accumulated dirt,
debris and
contaminates. This
includes power
brushing systems,

Portable electric

Portable electric
vacuum collection
systems offer the most
flexibility in that you
can clean virtually any
type (residential,
apartments, condos,
light commercial and
commercial) of
building with them.
You bring these
collectors into the
building and position
them where you can
be the most
productive. You zone
off (divide up) the
HVAC system to
achieve the suction
you need to clean.
These units operate
on 110 or 220 volt, 50
or 60 Hz., and have
HEPA filtration.

portable gas vacuum

portable gas vacuum
collection systems are
less expensive than
truck mounted units,
but like them, they sit
outside and you bring
in the large 50’ to 100’
long suction hose to
connect to the
ductwork. Depending
on the system you
may or may not have
to zone off the HVAC
system to achieve the
suction you need to
effectiviely clean.
You are limited to
cleaning residential
and one or two story
commercial buildings.