Working Area Requirements
Spectrometer Fume Extraction
Thermo Scientific
iCE 3000 Series Pre-Installation Requirements Guide (P/N 9499 500 30031, Version 1.6)
5-13
•
The hood and the first meters of the duct become hot, especially
when working with a nitrous oxide flame. Thermo Fisher Scientific
recommends marking the hood over the spectrometer with a hot
surface marking.
•
No cables, plastics or other materials that can melt at temperatures
below 100 °C must be in contact with the outer surface of the duct
(even within suspended ceilings or behind other covers).
•
A centrifugal fan, preferably with plastic coated metal blades, must
be fitted into ducting connected to the hood over the flame.
•
The fan must be at least 6 m away from the hood (measured
through the duct).
•
A flow rate of at least 2800 L/min (100 ft
3
/min) through the duct
over the flame must be ensured.
•
Thermo Fisher Scientific strongly recommends installing an
automatic supervision of the air flow.
•
If it can be ensured that the flow rate is at least 10000 L/min
(355 ft
3
/min) and/or that only acetylene flames are used, the
distance between hood and fan can be reduced to 3.5 m.
•
The temperatures that effectively appear within the duct depend on
several factors. Therefore, Thermo Fisher Scientific strongly
recommends measuring the resulting temperatures within the duct
and at the fan under worst case conditions in the final installation,
to ensure proper dimensioning of the exhaust system.
Additional Considerations
Additional considerations for multiple installations where the tubes end
up into a single fan or duct are:
•
The overall sum of temperatures must be taken into account.
•
The minimum flow rate through the ducting over the flame must be
ensured. This is important especially for installations, where
multiple tubes end up into a single fan.
For Dual Atomizer
•
For instruments with two sample compartments, two separate
extractions are required. See
.
•
The hood over the furnace must extract at least 200 L/min.
