16
8. Security
8.1 Liquid CO
2
backup
Precautions for CO
2
use:
Properties of CO
2
:
•
Does not sustain life or combustion.
•
Présent en faible quantité dans l’air (0,03 %).
•
Makes the atmosphere unbreathable at concentrations exceeding 3%.
•
Accelerates respiratory rate, induces faintness, vomiting, coma or
even death.
•
Heavier than air (d=1.53).
•
Non-flammable, colourless gas with a slightly acidic odour at high concentrations.
•
When liquid CO
2
is released at atmospheric pressure, carbon dioxide snow is generated at a temperature of –
80°C.
Ensuing risks:
•
Risk of asphyxia. Loss of consciousness occurs when concentration exceeds 8 to 10%.
•
CO
2
builds up in low areas.
•
Risk of frostbite.
•
Risk of corrosion of steels in the presence of humidity.
Critical precautions to be taken:
•
Areas where CO
2
is stored or used must be well ventilated (extraction or ventilation at both high and low levels
in the room).
•
Areas liable to contain an unbreathable atmosphere must be indicated with a CO
2
– risk of asphyxiation hazard
pictogram.
•
Never enter a room that has contained CO
2
without taking predefined precautionary measures.
•
Eliminate links between areas where CO
2
is stored or used and low points (pits, drainage channels, basements)
where it could accumulate and render the atmosphere unbreathable.
•
Use a CO
2
concentration detector (or O
2
concentration detector) to check that the CO
2
concentration is less
than 0.5% (as recommended by INRS, French National Research and Safety Institute).
In case of asphyxiation:
•
Check the oxygen concentration in the room and then take the victim to the open air (taking an insufflator with
you).
•
Begin artificial respiration and call the emergency services.
In the event of a leak:
•
Do not enter the room without breathing apparatus if the carbon dioxide concentration is higher than 3%.
•
Close the valve on the cylinder.
•
Aerate the room at length, ensuring that low points are ventilated.
Precautions with regards to equipment:
Warning, cylinders are pressurised !
•
Handle cylinders with care.
•
Secure cylinders in place.
•
Do not expose cylinders to excessive temperatures.
•
Treat valves with care (operate gently, do not dismantle or lubricate valves).
•
Ensure that hoses and pressure regulators are fit for use. Check the condition of gaskets and use original parts
only.
•
Before installing the pressure regulating valve, open the valve briefly to expel dust (do not stand in front of the
valve outlet at this time).
•
Never transfer gas from one cylinder to another.
•
Never lay a cylinder on its side during use.
After use:
