Physical Hazards, Reaction Hazards, and Environmental Hazards

When dealing with any number of materials particularly in an industrial or occupational setting, knowing the properties of these materials is very important to ensure the safety of people and to prevent potential disaster.  The physical hazards of materials include things like engulfment, over-pressurization, thermal hazards, and more.  Engulfment is when an individual becomes completely “engulfed” by a material.  This means the material at hand can be a solid, liquid, or gas.  In the case of a solid, and individual could fall into a grain silo or be cover by dirt at a contraction site.  In the case of a liquid, an individual could fall into a brew tank, or an oil holding tank.  In the case of a gas a toxic gas could surround an individual.  Also pertaining to gas engulfment, this gas could than cause oxygen depletion by pushing away all the oxygen and suffocating the individual.  Over-pressurization is another physical hazard.  This is when the pressure of a material is too high for the container holding it.  This can happen when a material is confined and the ambient temperature rises.  With materials in the gas form, they generally follow the ideal gas law.  Meaning if their temperature doubles, so does their volume.  In the case of liquefied gases this is not so.  When a gas in liquid form is heated, the gas expands exponentially to around 400-600 percent its original volume.  This can pose a very serious danger.

  Thermal hazards are also very important.  Cryogenic materials and other super cooled materials like liquid nitrogen are cold enough to freeze flesh instantly.  This can be very dangerous because it can kill tissue very quickly.  On the opposite side of the coin, materials can also be extremely hot.  Many chemical reactions produce a substantial amount of heat that can burn and kill flesh very quickly as well.  Some materials reduce friction intentionally but when spilled, can pose a danger.  Slips, trips, and falls are very common workplace injuries.  Very fine powders like graphite or slick oils can make a walking surface very slippery and dangerous to workers.   Material reactions can be very dangerous as well.  Materials can react to form dangerous gases, fires, explosions, and more.  It is very important to know if a chemical is compatible with the container you are putting it in, or other chemicals that may be stored with it.   Environmental hazards are something to be considered, especially when discharging materials.  A chemical that may appear harmless, or is harmless to a human may in fact be very dangerous to the ecosystem, or a specific organism in that eco system.  These materials can also accumulate in an organism’s body over time, this is called bioaccumulation.  Many materials have warning properties that will let you know if they are present.  One example of this is natural gas.  When natural gas is leaked, an individual can usually smell it and knows it is present.  Warning properties include a materials visibility, odor, irritation of senses, dizziness, and taste.  However some chemicals may be very hazardous and have no warning properties.  A good example of this is carbon monoxide. 

A materials genealogy is also crucial to be knowledgeable of.  This means, were the material was processed/purified, and how its properties change over time.  A material can “go bad” just like food can.  It is crucial to know the hazardous properties of any material when dealing with them.  Failure to do so can result in injury or even death for an individual.