Architect and Builder Magazine South Africa March/April 2014 | Page 64

Air extraction from a
variety of different types
of fume cupboards is done
with a dedicated duct
system to the roof of the
building for ventilation to
the atmosphere via filtering
systems and scrubbers

ROOF SERVICE LEVEL - CABLE RACKS

FUME HOOD EXTRACTION

with hazardous materials from one laboratory
to another.
The supply cables were installed from the
substation on vertical cable ladders to main
distribution boards on each of the six floors.
Cables to sub distribution boards on the
benches were installed on horizontal cable
ladders in ceiling voids and co-ordination of the
routes and other services was critical.
A sub-distribution board is provided for each
laboratory bench module. This allows control of
the bench with direct line of sight. In event of a
circuit tripping this will be isolated to a single
laboratory bench.
Normal, dedicated, UPS socket outlets and
outlet points were installed in a horizontal
service shelf in the middle of each bench on
a comfortable height to make it easy to plug
in equipment.

the respective laboratories. Fresh air systems
had to be carefully balanced with the laboratory
fume hood extraction systems to ensure that
extraction from the unit remained effective.

MECHANICAL SERVICES
Air Conditioning and Ventilation
The entire building is served by a chilled water
and steam heating air conditioning system.
Steam heating was used, due to the availability
of steam at the Sasol site to provide pre-heating
of fresh air.
Five chillers are located on the roof of the
building, with total capacity of 3 megawatt, and
are used to generate chilled water. Conditioned
air is distributed throughout the building by
means of a total of 188 off air handling fan
coil units.
Fresh air is circulated throughout the
building by means of a ducted system with an
average total air change rate of six per hour.
Certain areas have significantly higher air
change rates due to the particular activities in
64

Laboratory Fume Cupboard Systems
Air extraction from a variety of different types of
fume cupboards is done with a dedicated duct
system to the roof of the building for ventilation
to the atmosphere via filtering systems
and scrubbers.
A total of thirty nine normal fume cupboards,
five “walk-in” fume cupboards, fifteen normal
extraction hoods and twenty flexible Nederman
extraction hoods are used.
Eight specialist fume cupboards are used
i.e. Radio Active, Peroxide, Sulphur, Perchloric
and Cyanide.
Finishes
Criteria for the finishes in the laboratory required
hard-wearing and chemical resistant finishes
and fittings. Laboratory benches are provided
with TRESPA counter tops, grooved to allow
spillages to drip to the floor.
The floors are 100% rubber floors and
chemical resistant and are non-slip. The softer
finish provides greater comfort to the laboratory
technicians who are required to spend a large
part of their shift on their feet.
Cabinets are manufactured from timber as
the chemicals and chemical fumes are found to
corrode steel fittings over time.
The Microscopy Laboratory
High Resolution Transmission Electron Microscopes (HRTEM) are extremely sensitive to
electromagnetic interference, temperature
Sasol Infrachem