Glossary of Terms
- Michael Biarnes
Some of the more harmful indoor air pollutants can be accurately monitored using the AQ Expert VOC Monitor.
In general, almost all compounds that contain a carbon atom are considered organic.
Volatile Organic Compounds (VOCs)
Organic compounds that release many gaseous molecules from their liquid or solid forms due to their high vapor pressure and low boiling point. While there are many VOCs that are naturally occurring and important to environmental interactions, such as plant to plant exchanges, many VOCs are emitted in manmade processes.
The EPA defines VOCs as “…a large group of organic chemicals that include any compound of carbon (excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or carbonates, and ammonium carbonate) and that participate in atmospheric photochemical reactions.” It is important for VOCs to be carefully monitored, particularly indoors where concentrations tend to be higher, as they may have harmful effects to not only humans but also the environment. VOC monitors will help avoid serious issues caused by the dangers of VOCs.
- Common VOCs
- Formaldehyde, toluene, benzene, xylene, perchloroethylene, etc.
- A common VOC found in many man-made and naturally occurring products and processes including adhesives, ceiling tiles, automobile production, sanitary paper production, and paints to name a few. With the formula CH2O, Formaldehyde is useful in a plethora of fields and products, but must be monitored carefully as in higher quantities it can be an irritant that causes headaches, dizziness, and memory loss. Formaldehyde, as well as a number of other common VOCs, has been deemed as a carcinogen.
- A few sources of VOCs in need of monitoring:
- Vent Gas, Water Separation Techniques, Industrial Waste Water, Batch Processes, Petroleum Refining, Natural Gas Processing, Petrochemical Processes, Paints, etc.
an organic compound which only contains the elements Carbon and Hydrogen. Hydrocarbons can be further broken down into saturated and unsaturated forms.
Saturated Hydrocarbons consist of only single bonds and are also known as alkanes.
Unsaturated Hydrocarbons include at least one double or triple bond in its chain of carbon atoms and include alkenes and alkynes.
- Hydrocarbons including at least one double bond.
- Hydrocarbons including at least one triple bond.
Combustible Vs. Flammable Liquids
Combustible and flammable liquids differ in the temperature required to emit enough vapor to produce a flash when a spark or flame is provided.
- Combustible Liquids
- A liquid having a flash point ≥ 100°F.
- Flammable Liquids
- A liquid having a flash point ≤ 100°F.
Lower Explosive Limit (LEL)
The LEL refers to the minimum concentration of a particular vapor needed to produce a flame in the presence of an ignition source. The lower explosive limit is also referred to as the lower flammable limit at times.