Binder CB-S 170 - Page 27

CB-S / CB-S-UL (E7) 06/2020 page 27/119
Notes on handling carbon dioxide (CO
2
)
Carbon dioxide (CO
2
) in high concentrations is hazardous to health. It is colorless and almost odorless
and therefore practically imperceptible. Vent out any CO
2
gas that may escape via good room ventilation
or a suitable connection to an exhaust system. We recommend installing a CO
2
warning system.
DANGER
Danger of suffocation and poisoning by high concentration of CO
2
(> 4 Vol.-%).
Death by suffocation.
∅ Do NOT set up chambers in non-ventilated recesses.
 Ensure technical ventilation measures.
 Observe the relevant regulations for handling CO
2
.
Observe the occupational exposure limit OEL for CO
2
set by the national authorities (formerly maxi-
mum permitted workplace concentration). Check compliance when operating all chambers located in the
room.
• OEL for Germany: 5000 ml/m3 (ppm) = 0,5 Vol.-%
• CO
2
lost with each door opening: about 16.4 g, i.e. 0.0084 cubic meters / 0.296 cubic feet (under nor-
mal pressure)
• CO
2
lost during 12h at 5 vol.-% without door opening: approx. < 2 g, i.e. 0.001 cubic meters / 0.035
cubic feet (under normal pressure 1013 mbar / 14.7 psi)
An example of how to evaluate laboratory volume and air change rate:
Question: Is an air change rate of 1/h sufficient for a lab with a volume of 100 cubic meters / 3,531.5
cubic feet with 10 CO
2
incubators, opened 4 times per hour?
Calculation: CO
2
concentration = CO
2
lost by door opening, multiplied by 10 chambers, multiplied by 4
door openings per hour, divided by lab volume
0.0084 cubic meters x 10 x 4 div. 100 cubic meters = 0.00336, i.e. 0.336% or 3360 ppm.
0.296 cubic feet x 10 x 4 div. 3,531.5 cubic feet = 0.00336, i.e. 0.336% or 3360 ppm.
Result: The maximum permissible value of 5000 ppm is not exceeded under these operation conditions.
Even when CO
2
or systems operated with CO
2
are handled carefully and appropriately, a residual risk
remains, which can lead to life-threatening situations under certain circumstances. Therefore we strongly
recommend continuous monitoring of CO
2
concentration in the ambient air of the CO
2
incubator. It must
be ensured permanently that the maximum permissible occupational exposure limit OEL for CO
2
(0.5 vol -
% CO
2
for Germany) is not exceeded.