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Personal Protection

Jump to: Hygiene, Eye Protection, Foot Protection, Skin Protection, Hand Protection, Respiratory Protection, Other Safety Equipment

Housekeeping

The laboratory should be kept clean and free from clutter, by regular maintenance. At the completion of each experiment, equipment should be cleaned and properly stored. Do not let unused equipment or chemicals accumulate in the lab. Do not use the aisles of the lab or the space in front of the emergency escape panels for storage. Dispose of all hazardous wastes in accord with the procedures indicated in this manual. Reagent bottles must be properly labeled — when pouring hold the bottle with its label to your palm to protect the label. Notify your safety officer of bottles whose contents are in doubt.

Hygiene

  • Wash hands often — always before eating, smoking, or leaving the laboratory. Washing should be an instinctive reaction to spillage of any chemical on the skin.
  • Never eat or drink in the lab — never use lab equipment as a food or drink container.
  • No food items should ever be stored or even cooled in a laboratory refrigerator. Food and beverages can become contaminated within a very short period of time to a life-threatening level by absorption of chemical vapors. Any food/beverage found in inappropriate areas will be removed without notice.
  • For more information see the OESO Laboratory Safety discussion on chemical hygiene at the following URLs: http://www.safety.duke.edu/LabSafety/ChemHyg.htm and 
    http://www.safety.duke.edu/OHS/ChemHygiene.htm

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  • Eye Protection

    Various types of eye protection listed in order of increasing effectiveness include:

    • Ordinary spectacles
    • Safety glasses with side shields
    • Protective goggles, which can be worn over spectacles, if necessary
    • Face shields
    • Head shields, which protect all of the head and throat

    Chemistry Department policy requires that all persons wear, at least, safety glasses (equipped with side shields), or goggles for eye protection while in the laboratory. In situations in which there is potential of a corrosive chemical being splashed into the eyes, safety glasses or goggles AND a face shield are required. In situations where there is potential for an explosion to occur, head shields are required in addition to safety glasses or goggles. Department policy on contact lenses in the laboratory is that you may wear contact lenses, but only if your eyes are protected as described in the preceding paragraph by safety glasses or goggles, with or without a face or head shield. Normal eye protection is required when you are wearing contact lenses since contact lenses provide little to no protection from chemicals in the eye. (In fact, contact lenses can complicate flooding the eye with water should a chemical get in the eye.) Plain lens safety glasses, with side shields are provided for chemistry employees (including all research students and teaching assistants) at no charge. Please see an Undergraduate Lab Manager or the Preparator. Prescription safety glasses are available (at your expense) through a local optometrist. Students who wear prescription glasses, and who do not wish to wear safety goggles (available at Bryan Center Store), must cover the costs involved in being fitted with prescription safety glasses. All undergraduates are expected to purchase and wear safety glasses at all times when they are working at their laboratory benches or in any area where hazardous activities could endanger their eyes. Teaching Assistants and faculty supervising them are expected to enforce this regulation at all times. Teaching Assistants are reminded that the safety performance of classes under their regulation is one of the criteria by which they will be evaluated by the faculty.

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    Foot Protection

    All persons in labs must wear shoes (bare feet or sandals are not allowed) and adequate clothing to protect the skin from spilled chemicals.

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    Skin Protection

    Always wear clothing that minimizes the amount of skin that can be exposed to potentially harmful chemicals. Never wear shorts in the lab. A lab coat or apron should be worn when working with hazardous materials. From DUKE OESO News, December 1997, Vol. 5, Number 4, pp 4-5. Of the ways chemicals can affect the human body, exposure through skin contact is one of the most significant. The skin does a wonderful job acting as a barrier to those conditions normally encountered in the environment; however, as our workplace environments use more and more chemical substances, our skin can no longer provide adequate protection on its own. Chemical substances can act on unprotected skin in three ways:

    • Local Damage The action of many chemicals is limited to the skin itself. Corrosive burns, irritation, and chafing due to loss of skin oils are a few examples.
    • Sensitization Sensitizer chemicals may not have any initial effect, but will cause the skin to react, during subsequent exposures, to quantities much smaller than would otherwise have any affect.
    • Absorption The skin provides no barrier against some chemicals, which can penetrate freely and enter the blood stream affecting such target organs as the liver and nervous systems.

    A chemical may cause damage by more than one of the above effects. Some examples include chlorinated solvents, such as ethylene dichloride, which will defat the skin causing irritation and tissue breakdown, also can permeate the skin possibly causing liver and kidney damage.

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    Hand Protection

    From DUKE OESO News, December 1997, Vol. 5, Number 4, pp 4-5. Our hands are the body parts most likely to be exposed to chemical contact under normal situations. Even though careful technique may help an employee avoid direct contact with a chemical; the potential for exposure still demands the use of protective gloves. The department of Chemistry maintains a small list of glove compatibilities . These charts are by no means complete. If you have any questions regarding the effectiveness of a glove with a specific chemical, contact OESO or visit the following glove manufacturer links:

    Selecting A Glove: What Material is Best?

    "Karen E. Wetterhahn, professor of chemistry.... in the the Sciences at Dartmouth College, died June 8 at age 48 from mercury poisoning....While preparing the mercury NMR standard in a fume hood, Wetterhahn spilled one to a few drops of dimethylmercury. The compound permeated the latex gloves she was wearing and was absorbed through her skin into the bloodstream." C & EN, June 16, 1997, page 12.

    In choosing a glove that will provide an adequate level of protection, it is important to keep three warnings in mind:

    • There is no such thing as an "impermeable glove"
    • No one glove material is a barrier to all chemicals
    • For certain chemicals, there is no glove material available which will provide more than one hour of protection

    All chemicals will permeate through all glove materials. This process involves absorption of the chemical at the outside surface, diffusion of the chemical through the glove, and then desorption of the chemical from the inside of the glove. Gloves are considered protective if the rate of this permeation process is slow enough that the chemical does not break through to the inside. Glove manufacturers use two measures of glove suitability: Permeation Rate; the amount of a chemical which is passed through a given area of glove material per unit time and Breakthrough Time; the elapsed time from initial contact of the chemical to the outside of the glove to the first detection of the chemical on the inside glove surface. The objective in choosing a glove should be to seek a low permeation rate and a high breakthrough time, keeping in mind some of these factors:

    • Temperature Permeation rates increase and breakthrough times decrease with increasing temperatures. You need greater protection if your chemical processes involve heat.
    • Thickness Permeation is inversely proportional to thickness. Breakthrough time is directly proportional to the square of the thickness. Double gloving can quadruple the duration of protection.
    • Solubility Permeation is a direct function of the solubility of the chemical in the glove material.

    Selecting a Glove: What Other Factors are Important?

    There are many other factors that must be considered when selecting the glove that best suits the task. In some cases, your task may require you to choose a glove material which has a higher permeation rate, but has other qualities which makes it better for your situation. Some of these factors include:

    • Resistance To Physical Damage Do you need a glove that resists abrasions, cuts, punctures or tears? A torn glove made of the perfect material is less protective than an intact glove made of another reasonably adequate material.
    • Flexibility Is the ability to feel or manipulate small objects important or can you use a thicker more protective glove?
    • Heat Resistance Do you have a hot operation? As stated above, heat increases permeation rates. In addition, heat can lead to the breakdown of the glove material.
    • Incompatibilities Are you using a variety of chemicals? Some gloves may be incompatible with some of the substances. A good example of this is Poly Vinyl Alcohol (PVA), a glove material with great resistance to solvents, but that dissolves in water.

    The intent of this article was to present an overview of the complex nature of selecting the correct glove for adequate protection. Users should consult chemical MSDS's, glove manufacturer's literature, and the OESO for assistance.

    General Guidelines For Glove Use, Care, and Hygiene:

    • Disposable latex and PVC gloves have an important role in laboratories and health care settings; however they are not suitable for direct contact with aggressive or highly toxic chemicals.
    • Sometimes the ideal glove is two gloves worn together, combining the advantages of both.
    • It is usually not necessary to replace reusable gloves unless they become discolored or show signs of damage. If you suspect that they have been contaminated, replace them immediately - once a chemical has begun to diffuse it will continue to diffuse even when the chemical on the outside has been removed. Never reuse disposable gloves!
    • Store reusable gloves away from chemicals. Even chemical vapors may cause damage.
    • The use of protective gloves within the laboratory is essential in many instances. However, it is important to realize that if you are wearing gloves while handling chemicals, you must never come in contact with any item that a person not wearing gloves could. For instance, if you are entering or leaving the lab, DO NOT touch the door handle with your gloves on. While you are clearly unaffected by this action, any contaminants on your gloves will be transferred to the hand of the next person that opens the door with an ungloved hand. Likewise, remove your gloves if you are pressing elevator buttons, using a computer keyboard, using a pen that might also be used later by yourself or another person not wearing gloves, etc. Also, do not touch your face, hair, etc. while wearing protective gloves.

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    Respiratory Protection

    Fume Hoods

    Fume hoods provide constant respiratory protection in all laboratories in the building. Such protection is adequate for most controlled experiments. In using the hoods in the building, the following facts should be kept in mind.

    1. Lowering the sash will increase air velocity and offer greater protection from toxic fumes. Normally the sash opening should be less than 18". If the sash is opened to a height greater than 18", an alarm activated. It is important to keep the sash below the 18" mark. The OESO periodically measures the airflow in the fume hoods. They have labeled the hoods with the maximum recommend sash height. If the sash is raised above the indicated height, then the airflow will fall below the minimum acceptable level of 75 feet per minute. If you have questions about the airflow in your fume hood, contact the OESO at 684-2794.
    2. Placing equipment no less than six inches in the hood will also reduce the possibility of fumes escaping into the laboratory.

    Additional information may be found in the OESO Laboratory Safety Manual or via the link on the OESO Laboratory Environment website labeled "OSHA Chemical Fume Hood Quick Facts".

  • What does that gauge on my chemical hood mean?

    (This section is being checked for accuracy.) The chemical fume hoods in the Department have been fitted with digital meters that provide the face velocity of airflow in feet per minute or FLO. FLO indicates the hood sash is fully closed so there is no face velocity. Makeup air is still being exhausted from the hood, but its velocity is not indicated on the guage. These gauges allow employees to check that the hood is functioning properly (i.e., have a minimum face velocity of 75 ft/min) every time they use the chemical hood. If a hood is not functioning properly, it should not be used and employees should call maintenance. Also place a sign on the hood so that others will not use it.

    Emergency Respiratory Protection

    There are two types of emergency equipment available for respiratory protection: air-purifying and self-contained. These should only be used by Safety Office Personnel or others who have been instructed in their use. If you have need of respiratory protection equipment, contact the OESO.

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    General Safety Equipment Available in Each Lab

    In each lab there should be the following safety equipment:

    • safety shower
    • eyewash station
    • one or two fire extinguishers
    • fume hood(s)
    • a first aid kit (which the research group is responsible for restocking with items purchased at the stockroom)
    • a flashlight for use in case of a power failure (optional - supplied by the research group)

    If you use any of the expendable safety items (such as a fire extinguisher), notify the OESO at 684-2794 as soon as possible so that replacements can be obtained.

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    Other Safety Equipment Available in French Family Science Center

    Spill Kit

    Adjacent to the ice machine on the first level (hallway near 1112) there are spill kits for handling common spills involving 1) Solvents, 2) Acids (not for use with HF spills) and 3) Caustics. Directions for the use of each kit are provided with each kit. If you use one of these kits, notify the Lab Preparator (x1517, Room 1214) so that the used kit will be replaced. The used materials from the kit are to be kept in your lab (in a hood) and are to be treated as a hazardous waste. It is necessary to fill out a form requesting that this waste be removed from your lab by the OESO. (See the section dealing with disposal of waste chemicals later in this manual.)

    Last updated on 7/25/2013
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