The paper "Fatal Explosion at the School of Applied Sciences during Laboratory Study of Basic Aspects of Acids" is a worthy example of a case study on chemistry. On January 20, 2009, at 3.20 PM, a group of fifteen students at the Arizona State University was involved in a fatal explosion at the school of applied sciences, in the chemistry laboratory where they were doing an experiment using reagents at the laboratory.
The fifteen students who were involved in the accident were second-year students at the school of Applied sciences and the laboratory experiment was being carried out by the professor to demonstrate to them some basic aspects of acids. As it is in their curriculum, they are supposed to test the properties of acids and bases by mixing them in order to identify those properties. A variety of acids are tested and students are supposed to view those results by themselves and record first-hand results as viewed by them. There are many acids which are mixed with bases using beakers, the measurements are controlled by the professor and the students are expected to be closely watching the experiments.
It was during one of those laboratory experiments when the professor was supposed to mix Sulphuric acid and calcium hydroxide when an explosion occurred. It was reported that the container assumed to be containing calcium hydroxide was not actually containing the base. It was hydrogen peroxide. The bottle was wrongly labeled by the laboratory technician on duty. When the two were mixed, apparently in excess, the mixture exploded splashing the contents on the professor and the students. The professor who was standing less than a meter from the reagents suffered first degree burns while ten students suffered second-degree burns as they were three meters away. The remaining five students had minor burns as they were standing ten meters away. Due to the nature of the explosion that involved acid splashes no first aid was done, all the victims had to be rushed to hospital where they were attended to. It is reported that this is not the first incident of this kind and this led to an investigation.
Under the University’s guidelines, it is strictly prohibited to mix any reagents in a laboratory without confirming the contents of the reagent bottle. All reagents should be given by the laboratory technician. In this case, it was realized that a group of malicious students had visited the laboratory and changed the contents of the bottle. This was because of the pending issues that had not been resolved by the administration. The laboratory technician also failed to test the reagents before giving them to the professor and this compounded the problem. From the findings, it was agreed that better methods of control were needed in order to avoid a repeat of such incidences. The laboratory technician was replaced because of negligence and strict rules have been put in places such as ensuring each reagent bottle is well labeled and that the laboratory technician conducts a test before releasing any reagents to students or professors.
An explosion occurred at the Arizona State University School of Applied Sciences laboratory on January 20, 2009, in which fifteen students and a professor were splashed with an acid mixture. The explosion occurred due to a mixture of sulphuric acid and hydrogen peroxide. The professor suffered third-degree burns, 10 students had second-degree burns while 5 had minor injuries. Investigations revealed malicious intentions by students and negligence on the part of the laboratory technician. It was agreed to enforce strict rules to govern experiments in the laboratory so as to avoid future incidences.
Hazard controls are steps that are initiated to protect people from exposure to a substance or system and the procedures required to monitor individuals’ exposure and their health to hazards such as chemicals, materials, noise, vibrations, etc. there are three main types of hazard controls and these include elimination or substitution, administrative controls, and engineering controls. An example of elimination control is when a hazard is something that can be removed such as a faulty machine. Examples of administrative controls include work policies such as wearing of protective equipment for example helmets, the timing of work and machinery among others. Examples of engineering controls include modification of plants, ventilation systems and design of systems to reduce exposure (Goetsch 120-250)
Fuel, heat, oxygen, and a chemical chain reaction are the four sides of the IH tetrahedron without any of them it will not work.
Modes of contaminants entry
There are basically four modes of contaminants entry into the body: ingestion where someone eats or drinks a chemically accidentally especially if they failed to wash hands before eating, inhalation where airborne contaminants such as gases, vapors can be inhaled into lungs, absorption where a contaminant such as a chemical may enter the body through the skin openings especially salts and powdery chemicals and lastly injection where a person may accidentally prick themselves with a contaminated object such as a knife (Goetsch, 120-250).
Definitions and descriptions of TLV-TWA, TLV-STEL, TLV-C, PEL
Threshold Limit value-Time-Weighted Average (TLV-TWA) is the average concentration of a chemical to which it is allowed to expose a worker over a certain period usually 8 hours. Threshold Limit Value-Short Term Exposure Limit (TLV-STEL) refers to the maximum concentration allowed for a continuous 15-minute exposure period. Threshold Limit Value-Ceiling exposure value (TLV-C) is an exposure limit that should not be exceeded under any circumstances. Permissible Exposure Limit (PEL) is an absolute value prescribed in regulations that sets out the maximum allowed exposure to a hazardous chemical (Oxford University).
Categories of industrial stressors
The four categories of environmental stressors include physical hazards caused by loud noise and vibrations, chemical hazards caused by chemical burns and explosions, biological hazards caused by viruses, bacteria vermin, etc. and ergonomic hazards caused by tools and work stations, lighting, etc. (Reese, 150-175).
Employers are required to train and provide information concerning classes of chemicals that employees may encounter at work. Secondly, Importers, distributors, and manufacturers are required to label containers of hazardous chemicals. Thirdly, Pharmaceutical manufacturers and importers are required to evaluate chemical hazards and document potential effects and lastly Hazard information must at all times be transmitted on Material Safety Data Sheets and must be distributed to the customer at the first time of the shipment of the product (OSHA).
Definitions and descriptions of aerosols, vapor, dust, mists, fumes, gases
Aerosols are liquid droplets or solid particles that are dispersed in the air e.g. aerosol from spray paints. Dust is airborne solid particles from 0.1- 25 microns generated from crushing, grinding or blasting materials. Fumes are airborne solid particles less than 1 micron produced when volatilized materials from welding condense in the air. Examples include fumes from lead soldering. Mists refer to suspended liquid droplets generated by agitating liquid into a dispersed state for example mist from pesticide spray. Gases are fluids that do not have a form and occupy space, for example, oxygen in oxygen cylinders. Vapors refer to the volatile forms of liquids or solids present in air through evaporation, for example, acetone (Reese 150-175 ).