Disposal of Chemical Waste

Disposal of chemical waste is something almost every major industry deals with.  Whether it be a service industry like an automobile repair shop or a production industry like a factory, most industries produce chemical waste.  This waste can be very dangerous and hard to deal with depending on the nature of its origin.  Chemical waste is any spent or left over chemical produced by a wide range of industry or processes.  

Chemical waste can be harmless to the environment and may be disposed of in the normal trash.  However, often times the chemical waste is some sort of danger to either human health, the environment, or is a hazard to storage.  Personally, I deal with the chemical waste from labs at Ohio University at my job for the Environmental Health and Safety Center.  A large portion of this waste is hazardous.  We look up the SDS’s for these chemicals and try to figure out were they came from.  The next step is to search for the reactive, corrosive, flammability, flash point and human/environmental risks and properties. 

It is also crucial to determine the acidity of these chemicals.  Strong acids/bases are to be picked up by an outside service while weak acids/bases can be diluted and than disposed of normally.  These properties are also crucial to be aware of because it can effect how long they can sit in that particular container.  An acid for example, can eventually eat through its container.  Also chemicals that are corrosive must be researched before stored in a container.  Many containers may only hold the chemical for a matter of seconds.  Other containers may be approved to hold the chemical but only for a few years.  This is a problem I have run into cleaning out labs at OU.  I have seen some chemicals eat threw their container, the shelf they were on, and part of the floor.  This happened due to neglect.  Often times I come across chemicals that are unlabeled.  This is very tricky because you have to assume the chemical is hazardous, and often times do pH tests on the mystery chemical.  Some industries pose threats of chemicals like solvents and petroleum hydrocarbons entering the storm water system.  In this case, like in an automobile service garage, an oil/water separator is often installed.  Another way of protecting the storm water system is to install fuel catch basins.  This is a raised curb often around fueling stations, the idea being if fuel is spilled it will be trapped in the curb, and than cleaned up.  These curbs are often equipped with ball valves to release water build up during rain etc.  Sometimes chemicals being disposed in research labs are considered narcotics; in this case they are brought to the police.  If the chemical is a very dangerous threat to the environment it must be handled by an outside source.  Often times industries produce a small amount enough of chemical waste it would be impractical to contently keep having a service come to dispose of it.  In this case the chemical may be stored by the company.  Chemical properties are to be known and considered for safety reasons listed above.

Requirements for Chemical Hygiene Plan

The purpose of a Chemical Hygiene Plan is to have a set of guidelines that employees can access and consult for procedures.  The Chemical Hygiene plan is to list standard operating procedures concerning the processes and tactics for carrying out tasks when dealing with hazardous chemicals.  A hazardous chemical is any chemical being used in the workplace that can cause any sort of harm to a person or cause any other damage.  Almost every production industry or lab uses some form of hazardous chemicals.  Many industries may use hundreds, even thousands of chemicals, each with there own unique set of dangers.  The goal of the CHP is to reduce exposure to employees of these potentially hazardous chemicals. 

This includes administering controls like personal protective equipment etc.   It is required that employees are aware of the location of the CHP.  The chemical hygiene plan should list permissible exposure limits (PELs) if applicable.  As well as the signs and symptoms associated with exposure to that particular chemical. The Chemical Hygiene Plan should list how to safety handle, store, and use the chemicals being used in the facility, as well as the proper way of disposing that particular chemical.  The Chemical Hygiene Plan should also list were the SDS’s on those chemicals that are being used can be found; in the instance someone needs to find further information.  In some cases Chemical Hygiene Plans will list what actions need prior approval by either an employer or by a separate entities before they are carried out.  This can be for many reasons, like to prevent an environmental release.  The chemical hygiene plan also designates the proper places to either deal with certain chemicals or to conduct certain processes.  An example of this would be mixing two chemicals udder a designated fume hood.  Or having a designated painting room with a separate ventilation system.  Many actions in a laboratory or occupational setting can be harmful if not carried out in the correct place, so it is crucial employees are aware of this section of the Chemical Hygiene Plan. 

In the blood borne pathogen lab at OU, all of these factors in the Chemical Hygiene Plan are relevant.  Of course we are dealing with students oppose to “employees” but the concept is the same.  If any thing the fact that we are dealing with students in this case is a greater reason for concern.  Because students are going to have a lot less experience than someone who is actually working full time in a lab.  Working with diseases in human blood is especially dangerous, because you could infect yourself.  So in that scenario, it is important that the Chemical Hygiene Plan is very stressed, and is well known amongst the students, it is also very important that the person who heads the lab enforces what is written down in the Chemical Hygiene Plan.  There is no point in having a Chemical Hygiene Plan if it is not enforced; having a safety culture in the lab is very crucial to ensuring the safety of those who are working in the lab.

Cryogenic Liquefied Gases

Handling cryogenic gases/liquids pose a very serious safety risk.  When referring to cryogenics we are usually talking about gases that are so compressed they become liquids and are extremely cold.  Cryogenic gases/liquids have boiling points below -150 degrees Celsius.  All cryogenic liquids are gases at room temperature and normal pressure. 

The cylinders the gases are stored in are under very high pressure, which poses a large risk.  Due to pressure contained in the cylinders, there is an explosion risk and risk of oxygen displacement/asphyxiation if the gas is suddenly released.  These gases are at such a low temperature they will flash freeze whatever they come in contact with when released.  Cryogenic liquefied gases are handled in extremely insulated and strong containers.  Having such a highly insulated container reduces the risk of evaporation.  Full body protection is recommended when handling these super cooled materials as well as pre-planned medical action and services.  It is important to use only hardware meant for cryogenic materials when dealing with them.  Some equipment may seem suitable at first but does not have the qualifications and can cause an accident.  When an individual is exposed to cryogenic gas the pain is not immediate.  Blood circulation is arrested fairly quickly.  The skin will be severely “burnt” if not completely frozen and infection may result down the line.  Cell deterioration is a large threat because many cells exposed to the extreme temperature will die after thawing.  The reason these gases pose such a high risk of oxygen/air displacement is because of their rate of expansion.  A typical cryogenic liquefied gas will expand from 1 cubic foot to 875 cubic feet when it is released from its container.  Considering an oxygen deficient environment only has to be at or below 19% oxygen to be considered dangerous.  Gas expansion can be a huge risk to human asphyxiation.  If a container is noticed to be leaking, the facility should be evacuated until the threat is no longer existent. 

When these cylinders blow up rapidly (oppose to slowly leaking out) they can cause major damage and danger.  There are scenarios were these containers have gone through cinder block walls and roofs.  This can also trigger a chain reaction. One cylinder can puncture another causing more and more cylinders to explode.  Human lives have been lost this way.  If the compressed gas is flammable it can cause a whole new threat.  If a fire is started the heat surrounding a cylinder can cause the gas/liquid in surrounding cylinders to heat up and expand.  This can cause another chain effect, which has obliterated buildings and facilities in the past.  This is why it is important to take great care in dealing with highly compressed gases.  If tanks are store outside, oxidation of cylinder walls can weaken the tank.  Also, employees must handle them will care being sure not to drop or hit tanks.  If the gas is flammable, a spark resistant wrench should be used when handling the tank.  It is crucial these tanks are equipped with some sort of safety chain when being stored to prevent being tipped over and damaged.