This week we discuss flammable materials (liquids/solids). The hidden hazard is what some chemicals produce when in a fire. These byproducts from combustion can be quite deadly. Pick a synthetic material (like nylon or PVC or one of the hundreds of other ones) and discuss what the possible toxic chemicals it would produce in a fire.
Reading and Resources
This week’s reading is: http://ezproxy.apus.edu/login?url=http://dx.doi.org/10.1201/b15019
Chapter 5. pages 229-299
Chapter 6. pages 301-322
One student per synthetic material, do not duplicate
First we need to look what makes liquids flammable its the gas above the liquid that is actually flammable. So Chapter 5 starts off with what factors and physical properties that influence the vapor content.
Boiling point (and physical properties that make up a boiling point like molecular weight, polarity and longer molecules). The vapor pressure is a measure of how much vapor this at a given temperature. The flash point and ignition temperatures are temperature points in which there is enough vapor that it becomes flammable under specific conditions.
Where can one find these parameters? A good place to start is looking at a MSDS (now called a SDS). In one of the additional resources a explanation of how to interpret a MSDS.
We continue to look at organic chemistry, the structures of organic compounds, the nomenclature, and some of the hazards. The same powerpoint on hydrocarbons (as a refresher) is in the additional resources section. Let us limit ourselves next to only adding one element oxygen to the mix of organic compounds. This one element has dramatic effect on the physical and chemical properties of hydrocarbons. A powerpoint of organic compounds that contain oxygen (or sulfur) is included in the additional resource section.
Now I also added in organic compounds that contain sulfur. They mimic the compounds the contain oxygen surprising well in terms of there structure, nomenclature and even some of the hazards. It is a good place to introduce them here. Unfortunately there are no videos.
Flammable solids oddly enough contain some liquids. DOT hazard 4.2 spontaneous combustibles has both solid and liquids. Most of these solids and liquid are exceptionally reactive to air and water. Some solid compounds have a vapor pressure (like paradichlorobenzene) and thus could be flammable. In previous chapters, dust was considers explosive but dust (sawdust, grain dust) are also examples of flammable solids. Spontaneous combustion is compounds that react with air, such as animal/vegetables oils and pyrophoric solids and liquids. Lastly there is the chemicals that react with water that produce a flammable gas and enough heat to ignite the flammable gas. Once the chemical has been identified use trusted resources like the ERG, Cameo Chemical and CHEMTREC (see useful website found in the resource tab).
Please include a REFERENCE(S) (journal article, book, website, etc..) or specific example to support your discussion.