Lab Safety Modules

Note: There are two ways to view this document. 1) as a Word document, downloadable and printable, click here, and 2) in the table of contents below, click on the link you are interested in and the web site will automatically direct you to the linked location.

Table of Contents

1. Chemical Container Compatibility
2. Chemical Storage (compatibility with each other)
3. Compressed Gasses
4. Ethidium Bromide Use
5. Formaldehyde and other aldehyde usage
6. Lab Fume Hood
7. Lasers
8. Perchlorates and Chlorates
9. Peroxides and Ethers, Dangers of
10. Phosgene Generation from Unstabilized Chloroform
11. Precautions for Reproductive Health
12. Seismic Bracing Considerations
13. UV Light

1. Chemical Container Compatibility

So you’ve separated your flammables from your oxidizers, your acids from your bases, but are the chemicals in the correct type of container? Cole Parmer link to has a great site on this very subject. Just click on the chemical of interest and it will rate several different types of container material from Excellent to Severe Effect.

For general guidelines, Princeton University suggests the following:

Take special care in choosing containers for the following wastes:

Helpful Links

Cole Parmer Material Compatibility ratings http://www.coleparmer.com/techinfo/chemcomp.asp

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2. Chemical Storage (compatibility with each other)

In regard to storing chemicals near one another it is important to know if the chemicals are compatible with one another. In other words, will they be good neighbors or will they react with one another and possibly cause damage to the lab and harm the building occupants?

To be certain that chemicals are stored properly, UAF has adopted the J.T. Baker color storage code system. This system organizes chemicals according to certain properties and then assigns that property a color. The idea is that chemicals of the same color can be stored together safely. The properties and colors are as follows:

Substances purchased from JT Baker most likely have a color code already on the label. EHS&RM has color coding labels for your use to mark the chemicals in your inventory. If this seems like a huge undertaking, please call our department at 474-5413 and we will be happy to help you out. Also, the Chemical Hygiene Inventory Worksheet lists the appropriate storage color codes for several different chemicals. If you can not find the color code for a particular chemical, give us a call at 474-5413.

Sometimes separating chemicals according to their compatibility may be more difficult than separating the acids from the bases. Some acids are incompatible with one another. Below is an excerpt from University of California Davis Chemical and Laboratory Safety Manual regarding acids and bases:

Helpful Links

San Diego State University – Partial List of Incompatible Chemicals http://bfa.sdsu.edu/ehs/partialist.htm

U of Massachusetts Boston http://www.ehs.umb.edu/incomphaz.htm

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3. Compressed Gases

Compressed gases may represent a hazard due to one or more of the following properties:

Each of these properties exhibits their own unique hazards and specific safe handling procedures must be followed.

Flammable gases must be stored in well-ventilated areas away (at least 20 ft) from oxidizers, open flames, sparks, and other sources of hear or ignition.
Inert gasses include argon, helium, and nitrogen. These gases are chemically inactive, odorless, tasteless, and colorless. This hazard class may cause suffocation by displacing the oxygen in the air. Some gases can act as simple asphyxiants by displacing oxygen in the atmosphere. As an example, the volume expansion ratio of liquid nitrogen (at 1 atmosphere and boiling point of –3210 F) is 696 to 1. The volume expansion ratio of liquid argon is 842 to 1. If there is a gas leak, shut off the source of the gas leak only if there is no risk to personnel and ventilate the area. Call 911 if medical attention is needed.
Oxidizers are nonflammable but can aid in the development of a fire by supplying an ignition source. Oxidizers should be stored separately from flammable gas containers or combustible materials.
Corrosive and toxic gases can cause serious injuries to unprotected personnel. Keep exposure to these gases as low as possible. Personal protective equipment such as gloves, apron, safety glasses or goggles should be worn when using these gases. Emergency showers and eyewash stations should be within 10 seconds away and the pathway to them should be free of clutter.
Cryogenic liquids can cause thermal burns upon contact with the body in addition to being flammable, an asphyxiant, and under pressure. Eye protection and hand protection such as insulated gloves should be worn to prevent contact with the liquid, gas, and associated equipment and piping. The Compressed Gas Association recommends wearing loose fitting gloves so that they can be removed easily in the event that liquid is splashed into them. The containers should be handled and stored in an upright position in well ventilated areas. These containers should also be equipped with a pressure relief device to relieve excessive pressures within the containers.

Fire and Building Codes apply to the amount and type of compressed gases that can be stored in a certain area. Call EHS&RM (x5413) or the UAF Fire Marshall (x7681) regarding quantity limitations.

There is much more that can be said regarding Compressed Gases Safety. There are excellent web sites that address other valuable information regarding the safe use and handling of these gases. Below is a list of a few of them.

Helpful Links

Princeton University http://web.princeton.edu/sites/ehs/labguide/sec_2f.htm

Stanford University http://www.stanford.edu/dept/EHS/prod/aboutus/documents/safetyman/gascylinders.html

Iowa State University http://www.ehs.iastate.edu/publications/manuals/gascylinder.pdf

East Carolina University http://www.ecu.edu/oehs/Training/CompressedGas.ppt

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4. Ethidium Bromide Use

Ethidium bromide (EB) is often used as a non-radioactive marker for identifying nucleic acid bands in gel-based acid separation. It is a potent mutagen which means it can cause a genetic mutation. It can be absorbed through the skin so always were nitrile gloves when handling EB. EB users should be certain to wash their hands after use even if gloves were worn. The user should also wear personal protective equipment that protects them from contacting EB such as a lab coat, closed toe shoes (always in a laboratory) and safety glasses. Goggles should be worn in place of glasses if there is a chance of splashing.

Ethidium bromide will fluoresce a reddish-brown color when exposed to UV light. EHS&RM has a hand-held UV light for examination of ethidium bromide residues. Labs using EB should have their space examined at least annually to make sure that there is no residue on faucets, fume hood handles, counter tops, etc. EHS&RM also has protective eye wear to use during the use of the UV light. Please contact EHS&RM (x5413) for an inspection of your laboratory space. This is not a finger pointing exercise put rather a way to ensure that you, your coworkers, and your students are working in an ethidium bromide free environment.

Helpful Links

University of Washington http://www.ehs.washington.edu/epohazreduce/ethidium.shtm

UC Berkeley http://www.ehs.berkeley.edu/pubs/factsheets/47ethidiumbromide.html

UC Davis http://www-ehs.ucdavis.edu/sftynet/sn-53.cfm

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5. Formaldehyde and other aldehyde usage such as paraformaldehyde, acetaldehyde, and butyraldehyde

Formaldehyde is widely used on campus for preserving or fixing biological cells and tissues. Formaldehyde is a suspected human carcinogen and a suspected reproductive hazard. Formalin is an aqueous solution that generally contains a 3 to 10% dilution of formaldehyde from the original 37-40% solution. Paraformaldehyde is the crystallized polymer of formaldehyde that is weighed out and dissolved in solution for experimentation or cell and tissue fixation. Typically, 3-10% formalin or paraformaldehyde solutions are used to perfuse or fix tissues.

Occupational Safety and Health Administration (OSHA) has set the 8 hour time weighted average (TWA) of formaldehyde to 0.75 ppm. A time weighted average is the exposure a person receives averaged over an 8 hour work day. In addition, OSHA mandates that no employee shall be exposed to formaldehyde in concentrations that exceed 2 ppm as a 15-minute Short Term Exposure Limit (STEL). OSHA regulations are law and every effort is made to comply with the regulations. The American Conference of Governmental Industrial Hygienist (ACGIH), a non profit, nongovernmental corporation suggests a more conservative exposure level. They recommend a ceiling level, or never-to-exceed level of 0.3 ppm.

OSHA also has a exposure level of 0.5 ppm called an Action Level. If exposures reach this concentration, some changes must be implemented to decrease the risk of exposures exceeding the TWA.

Exposure Monitoring

Unless there is objective data that shows the presence of formaldehyde cannot results in exposures above the action level or STEL, employee exposure monitoring is required. The monitoring can be conducted by EHS&RM. If you are starting a new process that uses formaldehyde or if you are unsure if your lab has ever been monitored for formaldehyde exposure, please call Tracey Martinson (x6771) to establish a monitoring plan. There are requirements on the frequency of monitoring based on the results of the initial monitoring. For details, contact the EHS&RM.

Where monitoring shows that the TWA of STEL has been exceeded, all entrances to the lab must be labeled with a sign that reads:

Danger
Formaldehyde
Irritant and Potential Cancer Hazard
Authorized Personnel Only

Minimizing Exposure

Exposure to formaldehyde can be irritating to the eyes, nose, and upper respiratory tract. In certain individuals, repeated skin exposure to formaldehyde can cause sensitization that may result in allergic dermatitis.

Here are a few tips to help limit your exposure:

Hazard Communication

Formaldehyde gas, mixtures, or solutions composed of 0.1 % formaldehyde or greater is subject to the hazard communication requirements. Labels on materials that are capable of releasing formaldehyde levels of 0.1 ppm to 0.5 ppm should at a minimum, list the name and address of the responsible party, and state that the physical and health hazard information is available from the employer and from material safety data sheets (MSDS). For materials capable of releasing formaldehyde at levels above 0.5 ppm labels should also include the works “Potential Cancer Hazard”. MSDS should also be available for the employees. An MSDS written by JT Baker for formaldehyde can be found here.

Employee Information and Training (this section is taken directly from University of Pittsburgh. It is a nice summary of the OSHA regulations)

1. Annual formaldehyde training is required for all employees exposed at 0.1 ppm or greater. Employees can be exempted from training if their specific lab activity has been monitored by EHS&RM and exposures are determined to be less than the OSHA training action limit (0.1ppm).

2. Formaldehyde training will address OSHA Standard provisions per 29 CFR 1910.1048 in addition to the signs and symptoms of exposure, safe work practices, use and limitations of PPE, emergency procedures, and spill cleanup.

3. The training will increase employees’ awareness of specific hazards in their workplace and the control measures available to reduce formaldehyde exposure. Substitution of less-hazardous preservatives or fixatives is encouraged.

4. Questions about formaldehyde use or training should be directed to Tracey Martinson at 474-6771.

Special Safety Precautions

If formaldehyde contacts the body flush with water in an emergency eye wash or shower for at least 15 minutes. Call 911 for emergency medical attention.

All solutions of formaldehyde and tissues preserved in formalin must be stored in tightly sealed, properly labeled, containers to prevent leaks, spills, and evaporation.

Do not pour formalin or formalin waste into sinks or drains. Formalin waste solutions must be placed in tightly sealed, labeled containers and segregated for disposal by the EHS&RM Hazmat Section (474-5617). Trace amounts of formaldehyde solutions such as puddles left on a tray after fixing tissue or examining a specimen may be absorbed with an absorbent. The absorbent material should also be placed into a tightly sealed bag and disposed of by the EHS&RM Hazmat Section.

Clean up small spills of dilute formalin only if you have the appropriate equipment to do so such as gloves and eye protection. Materials used to absorb the materials should be placed into a tightly sealed bag and disposed of by the EHS&RM Hazmat Section..

Do not attempt to clean up large spills. If a spill occurs that causes eye, nose, or throat irritation, evacuate the area, close all doors, notify other building occupants near by, and call 911 or EHS&RM Hazmat Section (474-5617). The Emergency Dispatch business line can be reached at 474-7721.

Helpful Links

University of Pittsburgh - Guidelines for the Safe Use of Formaldehyde (some of the sections above were taken from this site)
http://www.ehs.pitt.edu/AnimalUsers/Safe%20use%20of%20formaldehyde-IACUC.pdf

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6. Lab Fume Hood

For information regarding Lab Fume Hoods, click here.

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7. Lasers

The State of Alaska Physical Data Sheet outlines the hazards and the precautions very well. Below is information from their page:

Description
A laser is a device which produces a concentrated beam of electromagnetic energy. The beam of energy can be in the form of visible light or in the form of invisible infrared or ultraviolet radiation.

Lasers differ in many ways, but there are certain characteristics which all lasers have in common. For all lasers, the production of the concentrated beam of energy requires three basic processes. First, an energy source is applied to a solid, gaseous or liquid substance called the lasing material. The lasing material then produces radiation having a specific wavelength. Then by using mirrors, lenses and shutters, the light or infrared waves or ultraviolet rays are magnified and focused to produce the laser beam.

Lasers may be different from one another in several specific ways. The basic categories are:

Hazards

The hazards related to the use of lasers vary depending on the type of laser, the power of the laser, the purpose and manner in which the laser is used, and the safety features of the laser.

Health Hazards

Eye injuries are the most serious danger from laser beams. The cornea of the eye is like a glass window that allows light to enter the eye. It is located in the very front part of the eyeball. The cornea is very sensitive and injuries to the cornea can be very painful. Most injuries to the cornea heal without permanent damage. If the deep layers of the cornea are affected, permanent injuries can occur. The types of eye injuries which occur from improper use of lasers depend on the wavelengths of the laser beams. Laser injuries to the cornea are usually caused by lasers having short wavelengths in the ultraviolet and long wavelengths in the infrared ranges.

The lens of the eye is located toward the front of the eyeball but behind the cornea. Injuries to the lens can result in loss of transparency of the lens. The lens becomes cloudy and then blocks some of the light rays entering the eye, thus making it hard to create clear images on the retina. When the lens of the eye becomes cloudy, it is called a cataract. While damage to the cornea usually heals completely in a day or two, damage to the lens almost always persists. Very slight damage to the lens may go unnoticed, but repeated minimal damage can add up to serious damage later on. Damage to the lens may not cause problems until many years after the injuries to the lens occurred. Lens damage is most likely to occur with certain lasers that produce beams in the near-ultraviolet and near-infrared wavelength range.

The retina of the eye is the surface upon which visual images are produced. It is located in the back of the eyeball. Certain lasers in the wavelength ranges of visible light and near-infrared wavelength ranges can burn permanent blind spots in the retina causing partially or totally obscured vision.
Skin burns may also occur from the use of lasers but are less likely to occur and are less serious than eye injuries. When skin is exposed to a potentially dangerous laser beam, a person will usually feel the heat and remove the exposed part of the body from the path of the laser beam.

Electrical Hazards

Some lasers require high voltage power supplies and some workers have received electrical shock because of carelessness while working around these power supplies. Almost all laser power supplies under certain circumstances could possible cause electrical shock or electrocution. Following the general safety standards for other electrical or electronic equipment provides protection against the dangers of electrical shock or electrocution.

Chemical Hazards

Laser welding or cutting of metals will cause formation of many of the same metal oxides and other fumes that are produced in conventional welding processes. Explosions can occur when ice collects in valves or connectors in lasers which require very cold liquids, such as liquid nitrogen.

Lasers are commonly used in the workplace to perform the following functions:

Safety Classifications of Lasers

For safety purposes, lasers are divided into Classes I, II, III, and IV; Class I being least hazardous and Class IV most hazardous. Almost all reported eye injuries have been from Class IV lasers.

Almost all lasers that produce visible light beams are so bright that they can produce eye injuries. Therefore, to reduce risk of health hazards to the eye, many are designed in a way, such as enclosing the laser beam in a box, which prevents direct eye exposure to the beam.

Any laser which by itself is in Class II, III, or IV may be reclassified to a lower risk category if the laser beam is enclosed in such a way to decrease the risk of hazardous exposure to people.

Class I lasers are considered entirely safe even if used improperly. Class I lasers do not require any warning labeling. Some more hazardous lasers may be placed in the Class I category when they are part of a consumer or office machine which shields the user from the hazards of the laser beam. These machines, however, must have some type of warnings which are visible if the shields are removed.

Class II lasers are often referred to as "low-power" or "low-risk" lasers. These lasers are hazardous only when someone stares directly into the laser beam even though the beam hurts the eyes. Class II lasers require warnings to avoid staring directly into the beam.

Class III lasers are Moderate Risk or Medium Power lasers. They can produce eye injuries when the laser beams are viewed directly or when a sharp reflection is viewed directly. Class III is subdivided into Class IIIA and IIIB. Class IIIA is considered to be hazardous only when the laser beam is collected and focused by optical instruments, for example when surveyors look into a laser beam with a telescope-like instrument. Class IIIA lasers require warnings to prevent such hazardous practices. These lasers can cause serious eye injuries before someone who accidentally looks directly into the beam has a chance to blink.

Class IV lasers produce beams that when reflected, even if it is not a sharp reflection, may cause serious eye and skin injuries, and where the beam may be a fire hazard. It is critical that the dangers of Class IV lasers are clearly marked with warning signs.

Safety Precautions

Class I Controls

Class II Controls

Class III Controls

Class IV Controls

Fortunately, these high-power lasers are seldom used outside of research laboratories and restricted industrial environments where personnel access is carefully controlled.

These lasers should only be operated within a localized enclosure, or in a controlled workplace, or where the beam is directed into outer space. If a complete local enclosure is not possible, laser operation indoors should be in a light-tight room with interlocked entrances to assure that the laser cannot emit while a door is open.

Emergency Procedures

Anyone who is suspected of having a laser-related eye injury should be examined as soon as possible by an ophthalmologist, a physician who specializes in the care of eye injuries and diseases.

Laser-related skin burns should be treated as any other skin burns. Cold water should be applied immediately to the burn area for first and second degree burns (reddened skin or blistering skin). Third degree burns (open wound) should be covered with a sterile dressing and the person taken to a medical facility. Never put ointments, creams or butter on burns.

Permissible Exposure Limits

Lasers used in construction shall comply with the Alaska Construction Code, Section 05.040(e):

Nonionizing radiation

References

1. Sliney, D. & Walbarsht, M., Safety with Lasers and Other Optical Sources. Plenum Press, New York, NY 10013.

Helpful Links

State of Alaska Physical Agent Data Sheet for Lasers http://www.labor.state.ak.us/lss/pads/lasers.htm

OSHA Laser Hazards http://www.osha.gov/SLTC/laserhazards/index.html

Princeton University Laser Safety Guide http://web.princeton.edu/sites/ehs/laserguide/index.htm

Michigan Tech Laser Safety Guide http://www.admin.mtu.edu/fm/oshs/laser_safety/

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8. Perchlorates and Chlorates

Inorganic chlorates are strong oxidizer which means they aid in the combustion of other material. Because of the increased explosion potential, extreme caution must be used when working with perchloric acid and inorganic perchlorates.

The following information is taken from Appendix F of the University of California San Francisco Chemical Safety Manual. Appendix F is titled Safe Handling Guide for Corrosive Chemicals and the section below is Safe Handling Guide for Perchloric Acid and Perchlorates. Specific information such as phone numbers has been changed to reflect UAF numbers. Also, where UAF has additional protocols, information is given in italics to provide additional information. A link to the entire appendix is listed under the Helpful Links section of this module.

General Properties of Perchloric Acid

Perchloric acid is a colorless, fuming, oily liquid. When cold, its properties are that of a strong acid; but when hot, the concentrated acid acts as a strong oxidizing agent. Aqueous perchloric acid can cause violent explosions if misused, or when used in concentrations greater than the normal commercial strength of 72%. Anhydrous perchloric acid is unstable at room temperatures and ultimately decomposes spontaneously with violent explosion. Contact with oxidizable material can cause immediate explosion.

Perchlorates

Each perchlorate or perchlorate system must be separately evaluated as many are extremely sensitive. Organic solutions containing perchlorate salts are capable of violent explosions during evaporation or distillation operations. Small amounts of unstable organic perchlorates are formed which are less volatile than the solute being removed. Near the end of the operation, the temperature rises because of these less volatile components. The higher temperature is enough to detonate the concentrated perchlorate residue. Whenever possible, an excess of water should be present to prevent the accumulation and to slow the temperature rise. Distillation or evaporation of organic-perchlorate mixtures should be halted with enough heel to keep residues diluted. Shielding should be used between the apparatus and laboratory personnel in addition to wearing personal protective equipment.

Fire and Explosion Properties

Perchlorate fumes and dusts are irritating, and the acid can cause severe burns to the eyes, nose, and throat. The literature for more than a century reveals descriptions of explosions in laboratories using perchloric acid. The accidents are usually very severe, with the primary cause being contact of the acid with organic material, or the accidental formation of the anhydrous acid. There is an extreme hazard encountered when strong reducing agents come into contact with concentrated (72%) perchloric acid.

A water spray can be used to extinguish small fires and cool fire-exposed containers. Water is also the best preventative measure against the occurrence of such fires. However if more than a small contained fire is involved, vacate the area and notify the police. (UAF policy is that students and employees evacuate the area and call 911. The fire department can also be reached by activating a pull down station located near the exits of nearly every building. Faculty, staff, and students are not encouraged to fight a fire).

Handling and Storage Guides

Perchloric acid should not be purchased, stored, or handled until the potential user is familiar with the hazards and has read the manufacturer's MSDS and this module.

Do not store perchloric acid near or in contact with combustible materials such as cotton, wood, excelsior, paper, burlap, rags, grease, oil, or organic compounds. Perchloric acid must be stored separately in a deep glass tray with sufficient capacity to hold the entire contents in case of breakage. Storage should be within a fume hood designated solely for perchloric acid use. The bottle and tray should be rinsed daily and after each use. All glass apparatus used should also be rinsed thoroughly. If any discoloration of the liquid is noted, the acid should be discarded by calling EHS&RM Hazmat Section (x5487) to request a chemical waste pick-up.

The use of perchloric acid should be limited as much as practicable and the quantity on hand should not exceed one 450g (1 lb) bottle. Order only 60% solutions; remember that the vaporization of perchloric acid in a chemical fume hood is prohibited unless it has a water wash-down capability. Such hoods are designed to preclude the formation of explosive compounds.

Glass hoods (fume eradicator with or without a reflux head or with a dropping funnel) can sometimes be used to effectively control fumes which are generated by perchloric acid digestion methods. These glass hoods, which are intended as temporary control measures for short term procedures only, are commercially available from laboratory supply companies. You must obtain permission from EHS&RM prior to the purchase of such hoods.

The glass surface tends to discourage the build up of perchlorates. However, the equipment should be thoroughly rinsed and cleaned routinely after use. Change the scrubbing solution (sodium hydroxide) after each use, since saturation of the solvent may occur and cause a carry over of toxic materials into the sewage system (this is to be avoided).

Maintenance or Suspected Contamination

If a fume hood is suspected of having perchloric acid contamination, call EHS&RM at 474-5617 or 474-6771 and request a survey of the suspected hood. The hood should also be surveyed for the presence of perchlorates prior to maintenance work. EHS&RM may check suspected surfaces with a solution of diphenylamine sulfate (1 gram diphenylamine in 100 ml of 1 to 1 H2SO4). The liquid turns black upon contact with a perchlorate. The solution also reacts with nitrates by turning blue. An alternative test for perchlorates uses a solution of methylene blue in methanol. In the event of a spill, contact EHS&RM if assistance is needed for cleanup. Otherwise, spills should also be reported to EHS&RM for verification that a clean-up has been properly completed and that no perchlorate hazard exists.

Personal Protective Equipment

Protective clothing consisting of rubber gloves, chemical safety goggles and/or face shield, and rubber apron should be worn when working with perchloric acid. Contaminated clothing is flammable and must be removed and washed thoroughly with water. Do not dry with heat.

Protective Procedures

1. Order 60% perchloric acid solutions or less.

2. Wear personal protective clothing and eye wear.

3. Transfer acid over a sink or deep glass tray to catch spills and afford a ready means of disposal.

4. When conducting perchloric acid procedures involving wet combustion, first treat the sample with nitric acid to destroy easily oxidizable matter.

5. Procedures involving heating of the perchloric acid must be conducted in an EHS&RM - approved perchloric acid hood.

6. Do not store any organic materials in the perchloric acid hood.

7. Do not allow perchloric acid to come in contact with strong dehydrating agents (e.g. fuming sulfuric acid, anhydrous phosphorus pentoxide).

8. Standard analytical procedures from authoritative analytical texts should be followed when working with perchloric acid.

9. Perchloric Acid (Greater than 60%): The following additional practices are required.

Materials

The hazards of breakage due to thermal or mechanical shock are sufficient to warrant quartz apparatus; especially, if it is necessary to chill from boiling. Glass, TeflonTM, and DurironTM can be used with perchloric acid. "O" rings and seals made of one of the fluorocarbons such as "VitonTM" are acceptable. For heat transfer or lubrication "FluorolubeTM" has been used. Fume hoods should be constructed of stone, PVC, or transite.

Stirrers

Pneumatically driven stirrers, as opposed to the electric motor type, should be used to minimize the fire hazard.

Heating Source

Hot plates (electric), electrically or steam heated sand baths, or a steam bath are recommended for heating perchloric acid. Direct flame heating or an oil bath should never be used.

Spills

Perchloric acid spilled on the lab bench or floor presents a definite hazard. Do not mop or soak up the acid spill with dry combustibles. First, neutralize the spill with soda ash and flood with large amount of water. Then, soak up with rags or paper towels. Limit the flooded area by using inert sand around the spill. Keep contaminated rags and paper towels wet to prevent combustion upon drying. Discard into a plastic bag, seal, and place in a flammable-waste disposal can, not in the ordinary trash. Clean the spill only if it is small and the user has the appropriate cleaning materials and personal protective equipment (PPE) to handle the spill. If it is large spill, or if the correct type of materials are not available, or if the user is not trained with the clean up procedures, please call EHS&RM at 474-5617.

First Aid

In case of contact, immediately flush skin or eyes with plenty of water for at least 15 minutes and call 911. If swallowed, DO NOT INDUCE VOMITING. Give large quantities of water or milk if available.

Helpful Links

Howard Hughes Medical Institute, Perchloric Acid Data Sheet http://www.hhmi.org/research/labsafe/lcss/lcss69.html

Texas Department of Health, Layperson Perchlorate Fact Sheet http://www.dshs.state.tx.us/epitox/default.shtm

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9. Peroxides and Ethers, Dangers of

Ethers
Ethers represent a class of materials which can become more dangerous with prolonged storage because they tend to form explosive peroxides with age. Exposure to light and air enhance the formation of the peroxides. A partially empty container increases the amount of air available, and hence the rate at which peroxides will form in the container. It is preferable, therefore, to use small containers which can be completely emptied, rather than take the amounts needed for immediate use from a large container over a period of time, unless the rate of use is sufficiently high so that peroxides will have a minimal time in which to form.

Ethyl ether, isopropyl ether, tetrahydrofuran, and many other ethers tend to absorb and react with oxygen from the air to form unstable peroxides which may detonate with extreme violence when they become concentrated by evaporation or distillation, when combined with other compounds that give a detonatable mixture, or when disturbed by unusual heat, shock, or friction. Peroxides formed in compounds by autoxidation have caused many laboratory accidents, including unexpected explosions of the residue of solvents after distillation, and have caused a number of hazardous disposal operations. Some of the incidents of discovery and disposal of peroxides in ethers have been reported in the literature, some in personal communications, and some in the newspapers. An “empty” 250-cc bottle which had held ethyl ether exploded (without injury) when the ground glass stopper was replaced. Another explosion cost a graduate student the total sight of one eye and most of the sight of the other, and a third explosion killed a research chemist when he attempted to unscrew the cap from an old bottle of isopropyl ether.

Formation of Peroxides
Peroxides may form in freshly distilled and undistilled and unstablized ethers within less than 2 weeks, and it has been reported that peroxide formation began in tetrahydrofuran after 3 days and in ethyl ether after 8 days. Exposure to air, as in open and partially emptied containers, accelerates the formation of peroxides in ethers, and while the effect of exposure to light does not seem to be fully understood, it is generally recommended that ethers which will form peroxides should be stored in full, air-tight, amber glass bottles, preferable in the dark.

Although ethyl ether is frequently stored under refrigeration, there is no evidence that refrigerated storage will prevent formation of peroxides, and leaks can result in explosive mixtures in refrigerators since the flash point of ethyl ether is -45 º C (-49 º F).

Isopropyl ether seems unusually susceptible to peroxide and there are reports that a half-filled 500-ml bottle of isopropyl ether peroxidized despite being kept over a wad of iron wool. Although it may be possible to stabilize isopropyl ether in other ways, the absence of a stabilizer may not always be obvious from the appearance of a sample, so that even opening a container of isopropyl of uncertain vintage to test for peroxides can be hazardous. C.R. Noller in Chemistry of Organic Compounds, W.B. Saunders, Philadelphia, 1951, comments that “neither hydrogen peroxide, hydroperoxide nor the hydroxyalkyl peroxide are as violently explosive as the peroxidic residues from oxidized ether.”

There are methods of detecting, estimating and removing peroxides; however, the safest method is to call to call EHS&RM Hazmat Section (474-5617) to perform the appropriate action.

Helpful Links

Colgate University Chemical Management, Peroxide Forming Chemicals http://offices.colgate.edu/chemmgt/CHP/n-peroxide.html

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10. Phosgene Generation from Unstabilized Chloroform, Dangers of

Chloroform is used in many organic extraction methods in molecular biology. It is recommended that it is stored in a dark place in an amber bottle and used only in a vented fume hood. Phosgene (used as a war gas in WWI) is a breakdown product of chloroform. Phosgene exposure can cause damage to the central nervous system in concentrations at only a small fraction of the permissible exposure limit of chloroform. Chloroform, stabilized with alcohol, should be purchased in the future whenever possible. If non-stabilized chloroform is necessary for the work, it needs to be treated like peroxide forming compounds and be used up in a short amount of time. Amylene is also used as a stabilizer, but there is evidence that it may not prevent phosgene generation. Any unstabilized chloroform older than one year, it should be discarded as hazardous waste. This can be accomplished by calling EHS&RM Hazmat Section (x5617) for a free pick up of the waste.

Lockheed Martin Idaho Technologies Company also suggests the following:

Helpful Links

US Department of Commerce/NOAA – Danger of Phosgene Generation from Unstabilized Chloroform http://micro.nwfsc.noaa.gov/protocols/chloroform.html

University of Bath – Chloroform – Phosgene could be lurking in the bottle. http://internal.bath.ac.uk/bio-sci/bbsafe/chloroform.htm

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11. Precautions for Reproductive Health

If you are pregnant or are in the planning stages of starting a family, it is never too early, or too late, to evaluate possible physical and chemical hazards in your work area. Substances or agents that affect reproductive health or the ability of couples to have healthy children are called “reproductive hazards”. These hazards may be from exposure to radiation, chemicals, drugs (legal and illegal), cigarettes, microorganisms, or alcohol. Hazards may affect the male reproductive system, the female reproductive system, and/or the fetus. (UC Davis)

Although some specific reproductive hazards have been identified in humans (e.g., lead, solvents, and ionizing radiation), most of the more than 1,000 workplace chemicals that have shown abnormal reproductive effects in animals have not been studied in humans. In addition, according to CDC Handbook of Laboratory Safety, 5th Edition, most of the 4 million other chemical mixtures in commercial use remain untested.

We suggest that females inform their supervisors of pregnancies so that the potential work hazards in the workplace can be evaluated. EHS&RM can help perform this evaluation and provide sampling, if needed, to quantify exposure levels. Perhaps one of the most frustrating concepts with this subject is the lack of complete data on chemical hazards to reproductive health and pregnancy. However, there are some guidelines that can help reduce exposure. These are listed below and are also contained in the UC Davis web site listed in the Helpful Links section of this module.

If you are pregnant or considering pregnancy and use any of the following types of chemical, you should call EHS&RM for a detailed evaluation of your work:

The most important thing you can do is know the hazards that are present in your work place so you can make an informed decision regarding whether you want to choose to continue working with those products. The Helpful Link section below contains several web sites with valuable information. The University of Bath, California Department of Health Services and UC Davis are especially helpful.

Helpful Links

OSHA – Reproductive Hazards http://www.osha-slc.gov/SLTC/reproductivehazards/index.html

University of Bath – Reproductive Hazards, Information for Workers Planning Families (this one is for the guys too)
http://internal.bath.ac.uk/bio-sci/bbsafe/reprohaz.htm

NIOSH – The Effects of Workplace Hazards on Female Reproductive Health http://www.cdc.gov/niosh/99-104.html

UC Davis – SafetyNet #108 - Pregnancy and Reproductive Hazards in the Workplace: Chemical and Radiological Hazards
http://www-ehs.ucdavis.edu/sftynet/sn-108.cfm

Perinatology – Exposure to Chemical During Pregnancy http://www.perinatology.com/exposures/chemlist.htm

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12. Seismic Bracing Considerations

Interior Alaska is in a geologically region that experiences earthquakes on a regular basis. Most of them are too small to be felt but they can be much bigger as the interior found out on November 11, 2002 after a 7.9 magnitude earthquake. Some damage as a result of a seismic event will be inevitable but there are a few precautions that employees can take to help minimize damage.

EHS&RM has a limited supply of seismic bracing equipment available for departments to have for their use. Please contact EHS&RM (x5413) for available materials.

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13. UV light

Similar to the Laser section, UV Light is one of the eight Physical Agent Data Sheets listed on the State of Alaska Labor Standards and Safety Division web site. Below is a copy of their web site regarding Ultraviolet Radiation.

Labor Standards and Safety Division

Physical Agent Data Sheet (PADS) -
Ultraviolet Radiation

Description

Ultraviolet (UV) is the name for a band of energy on the electromagnetic spectrum that lies between visible light and x-rays. UV has some of the properties of visible light and other properties of the x-rays. Like visible light, some UV is actually visible but most is invisible like x-rays. UV, like light, cannot penetrate very far into most solids. Some UV, like x-rays, can ionize atoms or molecules which visible light cannot do.

Common sources of UV include the sun (especially when reflected by water, snow or ice), sun tanning lamps, mercury discharge lamps, welding arcs, plasma torches, and some lasers.

Health Hazards

The nature and seriousness of UV injuries depend on the length of exposure, the intensity of the UV, the type or wavelength of UV, the sensitivity of the individual, and the presence of certain chemicals (photosensitizers).

Skin

UV from the sun causes sunburns and skin cancer. UV from other sources can also cause skin burns varying in degree from mild reddening of the skin (first degree burns) to more severe and painful blistering (second degree burns). Long-term skin exposure to UV can cause actinic skin (a dry, brown, inelastic wrinkled skin) and skin cancer. Fair skinned individuals are more likely to develop both sunburns and skin cancer.
Some drugs, such as the antibiotic tetracycline, can cause skin burns from UV to happen faster and to be more severe. Products containing coal tar can also cause this reaction. These substances are called photosensitizers.

UV exposure may trigger cold sores (Herpes Simplex) in some individuals.

Eyes

When UV is absorbed by the eyes and eyelids, it can cause keratoconjunctivitis or "welders' flash." This is a very painful condition that feels like grit in the eyes and may make the eyes water and very sensitive to light. The condition usually occurs 6-12 hours after exposure and may last 6-24 hours. The painful injury may make a person unwilling or unable to open his/her eyes during this time period, but most discomfort is gone within 48 hours with no lasting injury. The maximum sensitivity of the eye occurs at a UV wavelength of 270 manometers. Cataracts or clouding of the lens of the eye can occur during high exposures to wavelengths in the range of 295-300 nanometers.

Skin Safety and Health Precautions

Skin burns from high, short-term exposure to UV and skin cancer from long-term exposure can be prevented by covering exposed skin with clothing and protective equipment such as gloves and face shields.* Barrier creams or lotions with sun protection factors (SPF) of 15-18 will also help prevent skin burns.
* Welders' helmets should provide protection for the neck area as well as the face and eyes.

Eyes
Tinted goggles and/or face shields should be worn to prevent burns of the cornea and eyelids. Selection of the appropriate degree of tint should be based on the anticipated wavelength and intensity of the UV source. (see Table 1)

In sunny conditions on water, snow and ice, extra precautions should be taken to protect against reflected sunlight. Sunglasses with side shields should be worn. When applying protective ointments or lotions, special attention should be paid to the nose, lips, underside of the chin, and tops of the ears.

In workplaces, operations such as welding which produce high levels of UV should be performed behind enclosures or barriers to absorb the radiation and shield nearby workers.

UV sources like mercury discharge lamps should be operated only with all safety devices in place and in accordance with manufacturer's instructions.

First Aid Procedures

Skin burns: immediate application of cold (cold water, ice, cold clean cloths) to the affected area will reduce the severity and relieve pain associated with first and second degree burns. Do not apply any burn ointments, creams, or butter to skin burns.

Eyes: place sterile dressings over the eyes of a person suffering from UV burns of the eyes and seek medical attention.

Recommended Exposure Limits2

The following section is very technical and is included for the use of safety and health professionals who have the skills and equipment to measure UV levels.
These threshold limit values (TLVS) refer to ultraviolet radiation in the spectral region between 200 and 400 nm and represent conditions under which it is believed that nearly all workers may be repeatedly exposed without adverse effect. These values for exposure of the eye or skin apply to ultraviolet radiation from arcs, gas and vapor discharges, fluorescent and incandescent sources, and solar radiation, but do not apply to ultraviolet lasers. These values do not apply to ultraviolet radiation exposure of photosensitive individuals or of individuals concomitantly exposed to photosensitizing agents. These values should be used as guides in the control of exposure to continuous sources where the exposure duration shall not be less that 0.1 sec (Figure 1).

Figure 1

These values should be used as guides in the control of exposure to ultraviolet sources and should not be regarded as a fine line between safe and dangerous levels.

Recommended Values

The threshold limit value for occupational exposure to ultraviolet radiation incident upon skin or eye where irradiance values are known and exposure time is controlled are as follows:

1. For the near ultraviolet spectral region (320 to 400 nm), total radiance incident upon the unprotected skin or eye should not exceed 1 mW/cm for periods greater than 110 seconds (approximately 16 minutes) and for exposure times less than 10 seconds should not exceed one J/cm.

2. For the actinic ultraviolet spectral region (200 to 315 nm), radiant exposure incident upon the unprotected skin or eye should not exceed the values given in Table 2 within an 8-hour period.

3. To determine the effective irradiance of a broadband source weighted against the peak of the spectral effectiveness curve (270 nm), the following weighting formula should be used:

Eeff = ‚ E‚ S‚ ‚‚

where:

Eeff = effective irradinace relative to a monochromatic source at 270 nm in W/cm2 [J/ (s cm2)]
E‚ = spectral irradiance in W/(cm nm)
S‚ = relative spectral effectiveness (unitless)
‚‚ = band width in manometers

4. Permissible exposure time in seconds for exposure to actinic ultraviolet radiation incident upon the unprotected skin or eye may be computed by dividing 0.003 J/cm2 by Eeff in W/cm2. The exposure time may also be determined using Table 3 which provides exposure times corresponding to effective irradiances in ‚ W/cm2.

5. All the preceding TLVs for ultraviolet energy apply to sources which subtend an angle less than 80 degrees. Sources which subtend a greater angle need to be measured only over an angle of 80 degrees.

Conditioned (tanned) individuals can tolerate skin exposure in excess of the TLV without erythemal effects. However, such conditioning may not protect persons against cancer.

Reference

1. Sunlight and Man. Fitzpatrick et all Eds. University of Tokyo Press, Tokyo, Japan (1974).

2. Threshold Limit Values and Biological Exposures Indices for 1986 - 1987. American Conference of Governmental Industrial Hygienists, 6500 Glenway Avenue, Building D-7, Cincinnati, Ohio 45211-4438.

Helpful Links

Alaska State Department of Labor – UV radiation physical agent data sheet http://www.labor.state.ak.us/lss/pads/uv.htm

Princeton University Ultra-Violet Light Safety http://web.princeton.edu/sites/ehs/healthsafetyguide/E4.htm

University of Rochester – Ultra-Violet Light Safety Guidelines http://www.safety.rochester.edu/ih/uvlight.html

UC Davis SafetyNet #106 - Hazards of Ultraviolet Radiation http://ehs.ucdavis.edu/sftynet/sn-106.cfm

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Page last update on 4/11/07 by A.Chism