Very little known to the public and professionals, the dangers of carbon dioxide used in beer dispensers and carbonating machines are often underestimated. In fact, restaurants, bars and breweries constantly stock CO2 tanks for serving draft beers and soft drinks. Inhalation of high CO2 concentrations accumulated in confined spaces containing the gas cylinders causes many cases of sudden accidental deaths each year.
Carbon dioxide in bars and restaurants
CO2 & beer
Very widely consumed in bars and restaurants, beer is a carbonated drink, that is to say it contains carbon dioxide. In the case of alcoholic beverages like champagne, cider or beer, it is natural fermentation that produces the CO2 in the drink. Once in the drink, the goal is to not let it escape from the drink until customer consumption. This is where the beer tap and CO2 refill comes in.
While beer is the oldest man-made drink in the world, the beer tap was only invented at the end of the 18th century. The first beer taps were manual. You had to pump to see beer come out. Today they are refrigerated and under pressure.
The system’s operating principle is simple: carbon dioxide (or more rarely nitrogen) is stored in a cylinder and passes through a pump to go into a pressurized keg. So when you open the tap the beer spurts out, driven by CO2. The liquid leaving the keg is immediately replaced by CO2 and the beer does not lose any gas.
CO2 & soft drinks
In catering, in bars and other drinking establishments, places are very often equipped with a professional carbonating machine. This equipment is also known as a carbonated water machine or a carbonated drink dispenser. They enable mixing (syrup / water) and incorporate carbon dioxide to make sparkling sodas or sparkling water.
A professional sparkling water machine works with a water inlet, a syrup dispenser (if applicable) and a food-grade CO2 cylinder. Practical, economical and easy to use, this equipment can be found in a large number of all sizes fast food establishments, bars and restaurants.
The CO2 cylinder: gas risk in restaurants and bars
The food-grade CO2 cylinder: storage and use
In bars and restaurants, the use of a professional beer tap or carbonating machine requires addition of carbon dioxide. This contribution is made by a food-grade CO2 tank, rechargeable or not, from 2 to 10 kg. A 10kg CO2 tank can serve up to 70 beer barrels or 2,100 soft drinks liters.
While the use of CO2 cylinders in bars, breweries and restaurants is common, the danger they represent is not obvious to most managers and stakeholders in drinking establishments. Indeed, equipment malfunction, poor maintenance or incorrect handling of these cylinders can lead to a serious risk for all persons present in the establishment.
For all restaurants and bars, the CO2 cylinders’ storage question arises. We very often observe inappropriate storage in cellars, sheds, reserves or poorly ventilated rooms (likely to be confined spaces particularly prone to gas accidents).
The CO2 accident in bars and restaurants
Around the world CO2 accidents in breweries, bars and restaurants linked to carbon dioxide are very common. Unfortunately, there are many fatal accidents each year.
For example, if a 10 kg carbon dioxide cylinder empties completely in a 4 × 3 meter cellar, this results in an over 16% vol. CO2 concentration in the room. Like refrigerant gases, carbon dioxide is a gas that fills a volume by replacing oxygen. The suffocation risk is therefore the main danger associated with food-grade CO2 cylinders use. Stocks in bars and restaurants are particularly prone to this risk, but accidents can also occur when carbonating machines and beer taps malfunction or if tanks are mishandled causing a CO2 leak.
The CO2 danger in restaurants and bars
A CO2 leak can lead to a particularly dangerous concentration of gas for anyone on the premises. Indeed, carbon dioxide is an odorless, colorless and mostly harmless gas when it is in the air at usual concentrations (0.03%) but it very quickly becomes dangerous at higher concentrations.
|Carbon dioxide content (in %/vol.)||Effects on humans|
|20%||Respiratory depression, convulsion, coma and death.|
|10%||Visual disturbances, tremors, excessive sweating and arterial hypertension with loss of consciousness, in some subjects, if the exposure lasts about ten minutes.|
|5%||Headache, dizziness and first cardiovascular and vasomotor effects (heart rate and blood pressure increase, peripheral vasodilation).|
|4%||Increased respiratory rate, painful breathing for some.|
|2%||Increased respiratory amplitude.|
|0.03%||Normal concentration, no effect on humans.|
CO2 detection in bars and restaurants
The use of CO2 cylinders involves taking its risk into account. In order to guarantee maximum protection against CO2 dangers in bars, brasseries or restaurants, various measures must be implemented.
First, these CO2 cylinders should be stored in a well-ventilated room to avoid any accidental carbon dioxide accumulation. Second, monitoring the CO2 level in ambient air.
Fixed CO2 detector in bars and restaurants
In a bar or restaurant, installation of a fixed CO2 detector is the most relevant solution to protect people who could be exposed to too high concentrations of this gas. A fixed gas detector like the MGS450-CO2 would be ideally placed in the cylinder storage area (cellars, reserves, etc.).
It is a safety solution that will protect the place 24/7. The sound and light signaling integrated into the controller unit will warn the user before he is in danger.
Portable CO2 detector in restaurants and bars
Besides the installation of a fixed gas detector, the use of a portable CO2 detector is an interesting alternative to monitor carbon dioxide concentrations in drinking establishments.
This personal protective equipment will secure its wearer during the replacement of CO2 cylinders or while operating any work on the beer dispenser or soft drink machine. Using a portable gas detector will allow real-time measurement of CO2 exposure and provide accurate indication of the carbon dioxide concentration in the room.
Many portable CO2 detectors may be suitable with different advantages such as the small, unobtrusive and very popular iGas CO2 single gas detector or the X-am 5600 multi gas detector that can monitor up to 6 gases simultaneously.