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Refrigerant Detectors (Freons, Refrigerants)

Whether refrigerants used in cold storage or air conditioning systems, freon gases are imperceptible to humans (colourless, odorless) and therefore a freon detection The use of the system is essential. refrigerant gas detectors Its use faces several challenges in the refrigeration sector: safety of goods and people, costs associated with refrigerant leaks and environmental impact (subject to regulation).

Freon detection (refrigerant detectors)

Halogenated hydrocarbons belonging to the CFC and HCFC families have their own regulation: gas detection device Prohibiting or limiting its use with the obligation to install (refrigerant gas detectors). Refrigerants from other families are subject to regulations regarding chemical products, but common sense would also include monitoring for leaks.

Freons are generally heavier gases than air. They tend to stagnate in the ground and displace oxygen. Best detection of refrigerant leaks For , refrigerant gas detectors will be placed under the refrigeration unit and connected to a gas detection unit. In the event of a leak, the central gas detection unit will neutralize the cooling system by cutting off the power supply.

Freon classifications and categories

Freons are divided into several main categories based on their properties. Depending on the specificity of the needs, certain categories should be preferred:

  • Organic compounds: water, CO2 (carbon dioxide), NH3 (ammonia)
  • Hydrocarbons: butane, pentane, propane, propylene, etc.
  • CFCs (chlorofluorocarbons): R11, R12, R113, R115, R502
  • HCFCs (hydrochlorofluorocarbons): R21, R22, R123, R124, R401a, R402a, R408a, R409a
  • HFCs (hydrofluorocarbons): R32, R125, R134a, R15a, R143a, R152a, R404a, R407a, R410a, R507
  • Unclassifiable refrigerants: R630, R631, R12b1, R12b1, etc.

Refrigerants are rarely referred to by their international names because the pronunciation of their names is complicated. An abbreviation of the form R-ABCDe is preferred, R stands for refrigerant.

  • A: The number of double bonds is invisible if equal to 0
  • B: number of carbon atoms minus one (C-1), invisible if equal to 0
  • C : number of hydrogen atoms plus one (H+1)
  • D : number of fluorine atoms (F)
  • E: letter used to identify isomers (similar gross formula but not in semi-developed form)

For example, R134 is a freon consisting of 2 carbon atoms, 2 hydrogen atoms and 4 fluorine atoms.

Properties of refrigerants

With the exception of some organic compounds or hydrocarbons, refrigerants are generally not harmful to humans: they are non-flammable, non-corrosive and non-toxic. However, in case of abundant leakage, they replace breathable air, especially in poorly ventilated environments (hotel rooms, EHPAD, nurseries, schools, dormitories, etc.).

In addition to the risk of anoxia, some freons also have anesthetic properties, making them potentially dangerous; hence the need (and common sense) to install a leak detection system.

Practical guide to detecting refrigerants

The GTC Industrial team offers you a practical guide to detecting refrigerants. In this technical document you can find all the information and equipment available for the control of refrigerants in all your cooling applications:

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VOC Detection – Volatile Organic Compounds Detectors

Detecting VOCs (volatile organic compounds) is complicated because they tend to evaporate very easily at room temperature. They form a large family of gases and gaseous substances, many of which are considered pollutants, toxic or carcinogenic. Their volatile nature allows them to spread rapidly in the atmosphere, hence the need to detect and measure them to better protect ourselves. A variety of VOC detection techniques are available, from simple passive rosette to PID lamp and chromatography.

Detection of volatile organic compounds (VOC)

Their properties and health effects vary depending on their nature. They can range from simple olfactory disturbance to mutagenic disorders, various irritations and decreased respiratory capacity. VOCs Determination of toxicity (rather than explosiveness) in (fixed or portable) is much wiser to analyze the gas concentrations present.

In fact, the detection of VOCs There is a real illogicality about . Indeed, even if they are capable of forming explosive compositions, current concentrations must reach tens of thousands of parts per million (ppm). The main risk of volatile organic compounds is their toxicity at low concentrations on the order of a few tens of ppm.

5 VOC groups

Alkanes

Alkanes (or hydrocarbons) come mainly from petroleum products and contain only carbon and hydrogen atoms, such as: butane , ethane, heptane, hexane, octane, pentane or propane . In general, alkanes are not very reactive and play less of a role in ozone formation than other VOCs. 

Alkenes and alkynes

Alkenes and alkynes, acetylene, ethylene are unsaturated hydrocarbons characterized by at least one double bond (alkenes) or triple bond (alkynes) between two carbon atoms, such as isoprene or propylene. These are mainly used in the chemical industry and are produced during oil refining. Alkenes are more reactive than alkanes due to the presence of a double bond, alkynes are even more reactive (triple bond).

Aldehydes and ketones

Aldehydes and ketones are unsaturated organic compounds (also called carbonyl compounds) obtained as a result of incomplete combustion of fuels or wood, or chemical derivatives of an alcohol formed by the loss of two hydrogen atoms (ketones), e.g. acetone, acrolein, formaldehyde or MEK.

Monocyclic aromatic hydrocarbons

Monocyclic aromatic hydrocarbons, benzene, cymene, naphthalene, styrene , toluene or hydrocarbons containing a benzene nucleus, such as xylene.

Halogenated hydrocarbons

Halogenated hydrocarbons include chlorinated, brominated, or fluorinated hydrocarbons. These VOCs are present in the air due to their use as solvents, refrigerants, insecticides, or aerosol propellants such as chlorobenzene, chloroform, vinyl chloride, freons R11, R12, R22, R114, or trichloroethylene. These compounds are quite stable and can persist in the atmosphere for long periods of time.

Sectors of activity exposed to VOCs

Due to the impressive number of substances grouped under this name and their highly volatile nature, volatile organic compounds (non-exhaustive list) are present in a large number of industrial sectors such as: 

  • Cosmetics industry: deodorants, disinfectants, nail polish or nail hardeners 
  • Medical, paramedical and veterinary sector: alcohol, bactericides, insecticides
  • Food industry: disinfectants
  • Paper industry: Orange packaging, computer paper 
  • Industry and use of dyes and printing inks (preservatives) 
  • Industry and use of dyes and printing inks (preservatives) 
  • Textile industry: de-icing, bleaching of colored textiles
  • Leather and fur industry: preservation and tanning of leather, preservative 
  • Disinfection of premises: household detergents
  • Horticulture and agriculture: Bactericides, fungicides and herbicides 
  • Photography: stabilizers and stabilizers 
  • Exhaust gases from diesel engines
  • Fumes from burning wood, coal and polyethylene
  • Gasoline and oil refining