will take you back to the top of this page.
will take you back to the top of this page.
| Quick Links: |
Portions of this page have been adapted, with permission, from U of O's Chemistry Teaching Labs website.
As a student in an O-Chem lab, you might find yourself overwhelmed by all of the rules, regulations, and policies you are expected to follow, especially when you are handling chemicals. You might even wonder what all the fuss is about.
The "fuss" is that the chemicals in your lab are dangerous substances, considered to be hazardous to your health and safety. They are therefore subject to federal, state, and local legislation which is designed to inform you specifically of hazards of chemicals, and to specify safe and appropriate methods of handling and disposing of chemicals. The purpose of this section is to acquaint you with the relevant federal and local standards under which the Department of Chemistry (and therefore both the O-Chem stockroom and the O-Chem labs) operates.
In 1970, the Occupational Safety and Health Act established the Occupational Safety and Health Administration (OSHA) within the US Department of Labor. The original Act decreed that employees should be informed of all hazards to which they are exposed on the job. In the early 80's, OSHA implemented this instruction by enacting the Hazard Communication Standard (HCS) as 29 CFR 1910.1200, and the HCS became effective in 1986. A fundamental premise of the HCS is that employees who may be exposed to hazardous chemicals in the workplace have a right to know about the hazards and how to protect themselves. The HCS is therefore sometimes referred to as the "Worker Right-to-Know Legislation", or more often just as the "Right-to-Know" law. Although the original HCS applied only to the manufacturing industry, subsequent court challenges have expanded the scope of the law so that today the HCS applies to nearly all sectors of the work force.
Students are not, technically, employees of the University (unless, of course, you also have a job working for UNR). Strictly speaking, the HCS applies only to communication between employer and employees; however, students in teaching labs are subject to a related standard called the "Lab Standard", discussed below. Regardless of which standard is applicable, your safety is important and you should have access to the same information provided officially to employees under the HCS. For this reason, all chemical containers you encounter in lab are labeled in accordance with the HCS, and MSDSs are available for chemicals used in the lab.
As mentioned above, the Hazard Communication Standard (1910.1200), does not apply to certain kinds of laboratories. Laboratories, such as the teaching labs and research labs in the UNR Chemistry Department are actually covered by the Occupational Exposure to Hazardous Chemicals in Laboratories standard (29 CFR 1910.1450). This standard is also known as the "Lab Standard". Analogously, the University's Hazard Communication Plan (based on the OSHA HCS) specifies that laboratories are subject to UNR's Chemical Hygiene Plan (developed by the UNR Department of Enviromental Health & Safety and based on 29 CFR 1910.1450).
The Lab Standard is a more technical standard than the HCS, and includes additional material, such as requirements having to do with the proper maintenance of fume hoods and other safety equipment. As students in a chemistry laboratory course at the University, you shouldn't need to worry about the distinction between the HCS and the Lab Standard. The MSDSs, chemical labels, and other compliance measures that you will encounter will be exactly the same regardless of which standard technically covers your situation.
The UNR Chemical Hygiene Plan is available online from the EH&S Department. Copies are also available at the O-Chem stockroom.
It should be mentioned that this discussion so far has dealt with the federal OSHA HCS. The State of Nevada OSHA complies fully with all federal OSHA standards, having adopted them verbatim -- this is detailed in the Nevada Revised Statutes (NRS 618.295 and 618.305).
The Material Safety Data Sheet, or MSDS, is a document that gives detailed information about a material and about any hazards associated with the material. The HCS sets forth certain responsibilities having to do with MSDSs:
OSHA specifies that each MSDS must include, at a minimum, the information listed in the twelve sections below. Beyond that, OSHA does not specify the exact format of the MSDS, nor even how the information should be broken into sections, and so MSDSs prepared by different manufacturers tend to look different and contain different information. Even MSDSs for the same chemical can be quite different, if they were prepared by different manufacturers.
The OSHA-mandated MSDS information is as follows:
Note that the information above must be included in a MSDS. Often, additional information will be included, depending on which manufacturer produced the MSDS in question. There is no standard format for a MSDS.
The amount of information presented in a MSDS can be quite daunting to someone unfamiliar with the format. The challenge is in interpreting all the information supplied, and making sense of the sometimes confusing language. This is made more difficult because, besides the information which must appear on the MSDS (detailed above), there is no standardized format.
A good way to get an idea of the nature of a particular chemical from its MSDS is to read the hazards information (refer to the NFPA and HMIS sections in this document) and the toxicity information. The University of Oregon Chemistry Teaching Labs website has an excellent discussion of the interpretation of toxicity data contained in a MSDS, which is information usually contained in the "Exposure Limits" section.
If you are a UNR student, the EH&S Department offers a class in the interpretation of MSDSs. Contact John Davis for further details.
Of course, to thoroughly familiarize yourself with the hazards of a chemical, you will want to read the entire MSDS. If you have difficulty interpreting some of the language used in a MSDS (for instance, what do you do if a chemical causes alopecia or cheilitis? what precautions are necessary to prevent paresthesias?), here is an online MSDS Dictionary which defines hundreds of medical and technical terms used in a MSDS.
There are probably about as many places online to find MSDSs as there are MSDSs. Manufacturers provide online lists, and so do many universities and government agencies. What follows is a short list to get you started.
On the UNR campus:
Searchable Databases:
Manufacturer MSDS Databases:
Information about MSDSs:
The National Fire Protection Agency (NFPA), in section 704 of the National Fire Code, outlines a system for identifying the hazards associated with materials. The information contained in this section and the linked sections below comes directly from the 1990 edition of NFPA 704. Although the system was developed primarily with the needs of fire protection agencies in mind, it is of value to anyone -- including students enrolled in chemistry laboratory courses -- who need to handle potentially hazardous material.
The hazard identification signal is a color-coded arrangement of numbers and/or letters arranged in a diamond shape. An example is shown below. You have probably seen see hazard diamonds like this on trucks, storage tanks, bottles of chemicals, and in various other places. The blue, red, and yellow fields (health, flammability, and reactivity, respectively) all use a numbering scale ranging from 0 to 4. A value of zero means that the material poses essentially no hazard, and a rating of four indicates extreme danger. The white field is reserved for "special precautions". Two "official" values are specified in NFPA 704: "OX", indicating that the chemical possesses oxidizing properties, and "W", indicating that the chemical is unusually reactive to water. Other values sometimes appear here as well, including indicators for substances which are acidic, alkaline, corrosive, or those which present a radiation hazard.
Click on one of the four colored diamonds below for an explanation of the degrees of hazard associated with that color.
The Hazardous Material Information System (HMIS) is a labeling system developed by the National Paint and Coatings Association (NPCA) and sold through Labelmaster, Inc. An example of a HMIS label appears to the right. This system uses a label with four color bars and a blank bar at the top where the name of the chemical should appear. The HMIS system uses blue, red, and yellow colored bars. These bars indicate, respectively, the health, flammability, and reactivity hazards associated with the material. A numbering scale ranging from 0 to 4 is used in each of these bars, with a value of zero indicating that the material poses essentially no hazard, and a rating of four indicating extreme danger. The fourth, white bar is marked "personal protection". A letter (the letters used are A through K, and X) is placed in this bar to indicate the kind of personal protective equipment which should be used to safely handle the chemical.
Another very similar labeling system, the Hazardous Material Identification Guide (HMIG), was developed and is sold through Lab Safety Supply. This system is identical to HMIS with the exception that the fourth, white bar is marked "protective equipment" in the HMIG system.
Although the details of how numbers are assigned may vary somewhat between systems, the HMIS/HMIG system is essentially the same overall scheme as is used in the NFPA system, but there are differences.
As explained above, both the NFPA and HMIS/HMIG systems are similar to the extent that both use the same colors to indicate the hazards associated with a chemical (blue for health, red for flammability, and yellow for reactivity). Both systems also use a scale of 5 numbers (0 through 4) to represent the relative degree of the hazard, 0 indicating the least and 4 indicating the most hazardous.
The differences between the systems are minimal, with one exception. Obviously the layout differs (NFPA using 4 diamonds and HMIS/HMIG using stacked bars), but the most significant difference is the intended audience for each of the systems. The HMIS/HMIG systems were designed to be compliant with the HCS, and targets employees who must handle hazardous chemicals in the workplace. The NFPA system, however, was developed to alert firefighters to the hazards of materials present at the scene of a fire. Therefore the numbers assigned in the NFPA system assume that a fire is present. Since no such assumption is made with the HMIS/HMIG system, hazard ratings can differ from system to system, even for the exact same chemical.
It should also be noted that the manufacturers of chemicals and materials assign hazard ratings, rather than the government. Therefore, number values will change from manufacturer to manufacturer according to their individual interpretation of the level of hazard present.
However, despite any differences between systems or manufacturers hazard levels, a hazardous chemical will remain a hazardous chemical. Any discrepancy between the systems or between two manufacturers will only result in a hazard rating being changed by an increment of 1, at the maximum. A chemical rated with a health hazard of "4" by one manufacturer will never be rated lower than "3" by any other manufacturer.
In the O-Chem stockroom, NFPA hazard ratings are used if available. If not, then HMIS/HMIG ratings are used instead, according to information made available by the manufacturer.
The source of all published NFPA ratings is, of course, the NFPA. Some NFPA Standards which list ratings are NFPA 49, "Hazardous Chemicals Data", and NFPA 325, "Guide to Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids". HMIS/HMIG ratings can be found in some vendor and manufacturer catalogs, such as Spectrum.
Some online sources that list (NFPA) hazard ratings are:
In the O-Chem labs at UNR, reagent bottles are labeled using a system which includes a "hybrid" hazard labeling system.
When reagents arrive from the manufacturer, the labels are intended to communicate the hazards and precautions of handling a particular chemical to the researchers and professionals who will be using the chemical. Much of this information is also included in compliance with HCS legislation, to protect the manufacturer from liability for any accidents which occur during handling of the chemical.
Unfortunately for students in undergraduate-level teaching labs, this information carries little meaning, or is simply not interpreted correctly because the average undergrad hasn't had the training and education to fully understand the information presented. Therefore the OCS uses a simpler labeling system for the reagent bottles used by the students in the teaching labs. This system is a "hybrid" because it presents important information in a simpler and clearer format which is easy to understand, and also incorporates elements of both the NFPA and HMIS hazard labeling systems.
Here's an example of the labeling system we use:
The label consists of several parts:
A blank hazard rating on a chemical does not mean the chemical is harmless! On the contrary; it means that the chemical has not been rated by the NFPA or is not contained in any other published source of hazard ratings. Chemicals with blank hazard ratings should be treated as dangerous. Reagents which are not pure chemicals (for instance, aqueous salt solutions) will not include a hazard rating diamond on their labels.
There are many toxic, flammable, and otherwise dangerous chemicals that will be used in the Organic Chemistry Laboratory. It is prudent that all individuals participating in any experiment use gloves For glove safety information, please look here. Note: gloves should be used only as an added precaution. The use of gloves will not guarantee the prevention of injury due to exposure to chemicals. Yes, your hands will be better-protected from incidental contact with chemicals when you use gloves, but gloves are not by themselves able to protect you. The proper observance of safety precautions and use of common sense in handling chemicals will do more to prevent injuries than will the use of any type of gloves. The stockroom provides gloves for your use as a service to you, but it is up to you to practice safety in the labs for your own protection and the protection of others.
When in the laboratory and you are handling toxic chemicals (either solid or liquit), you should handle these chemicals in the fume hood for measuring or pouring. Handling toxic chemicals at your desk increases the risk of accidental skin contact and inhalation if there are any spills (or in the case of liquids, fumes). Desktop chemistry is an unfortunate byproduct of the large number of students in an organic lab class, but if you take care to handle the chemicals you use carefully, the possible danger of accidental negative contact is minimized.
Please do not pour chemicals back into stock bottles, not only is this rude lab technique, from possible contamination of reagents, but it can be dangerous as well - especially because most of these chemicals are reactive, releasing toxic fumes or producing other nasty results.
Again, please wear gloves! It is a simple precaution that cannot be stressed enough! Gloves are your first line of defense against chemical spills, splashes, other minor accidents. It's also a wise idea to purchase a lab coat from the ASUN bookstore or some other vendor. The lab coat should be 100% cotton or rubber, any synthetic fiber coat materials may dissolve in the event of a chemical spill.
Wear pants, long sleeve shirts, and low heeled-"full covering" shoes. Open toed and/or fiber topped shoes may not protect your feet from chemical splashes and spills.
Promptly replace all stock chemicals in the proper place, doing so will minimize search time - and accidental bumps and spills.
Know where emergency equipment is - and how to use it: the eye washes, showers, and fire extinquishers for quick response in the event of an emergancy. (It prevents panic and helplessness if you know what to do in the event of an emergancy.)
Organic Chemistry Stockroom | 
UNR Environmental Health & Safety
UNR Department of Chemistry |
UNR College of Arts & Sciences |
University of Nevada, Reno