June - July 1995

Fire Alarms:  Evacuating Effectively

Recently there have been instances of occupants refusing to evacuate when a
fire alarm goes off.   When a fire alarm sounds in a university building,
whether for a scheduled drill or otherwise, all occupants are required to
evacuate.

Security and fire department personnel arriving on the scene must
concentrate on discerning the cause of the alarm and protecting life and
property if necessary.  All occupants should be out of the area so firefighting
personnel can quickly and effectively locate and control any problems.  If it is
not a real emergency, then you will be allowed to return to your tasks as soon
as possible.

We realize that evacuating during alarms, especially when they frequently go
off, can frustrate ongoing work; however, the alternative-being trapped in a
fire-is much worse.  Please cooperate with this university mandate.

Fire emergency signs and exits are clearly marked on doors and hallways in
all campus buildings.  If a fire alarm goes off in your building, follow these
signs to the nearest exit.  Do not use the elevator.   If you have further
questions, contact Safety Services (x2907).


Drain Disposal:  what can you pour down the drain? 

The list of those substances that one can toss down the drain has become
considerably shorter since the passage of the Resource Conservation and
Recovery Act in 1976.  Any wastes perceived as hazardous by the
Environmental Protection Agency (EPA) can no longer be disposed of in this
way.  Below are some general guidelines concerning substances that cannot be
drain-disposed.

Any solution containing more than 24% ethanol, methanol, isopropanol,
or propanol.

Halogenated organics (solid or liquids); examples include: 
chlorobenzene, trichloroethylene, trichloroacetic acid, chloroform.

Non-halogenated organic liquids (aliphatic or aromatic); examples
include:  toluene, ethers, phenol.

NOTE:  The disposal costs for halogenated wastes are considerably higher
than for non-halogenated wastes.  PLEASE do not mix these wastes together;
otherwise, the entire container will have to be disposed of as halogenated
wastes.

Other miscellaneous solvents and mixtures; examples:  vacuum pump
oil, HPLC solvent mixtures containing organic solvents, and hazardous or
nonbiodegradable scintillation fluid (non-radioactive)

Organic solids still in the bottle; examples:  phenol, benzoic acid,
naphthalene, most common organic chemicals

Concentrated inorganic acids and bases; examples:  mineral acids,
ammonia, sodium hydroxide

Inorganic chemicals; examples:  copper chloride, mercury, mercuric
chloride, lead salts (in solid and solutions forms)

Dioxins

Special chemicals (poisons, explosives, health hazards, highly reactive
chemicals):

Known carcinogens and mutagens
Pesticides
Osmium tetroxide
Compressed gases (in non-returnable containers)
Chromic Acid


How to Dispose of these Wastes Properly

Each laboratory should retain waste chemicals in a container labeled with the
words "Hazardous Wastes," preferably plastic rather than glass.   When the
container is full, fill out a Hazardous Waste and Unwanted Chemical
Disposal Listing form (sample in Appendix Ia of CWRU's Chemical Safety
Manual), and send it to DOES at 216 Quail Building.  One of our technicians
will pick up the container as soon as possible.

Reducing the amount of waste created in the lab is also a way around having
to dispose of it.  We highly recommend that you use nonregulated substitutes
in place of those substances listed above.  If that is not possible, you can reduce
the volume of hazardous waste by reducing the scale of an experiment or
incorporating procedures in your experimental protocol which reduce the
type and volume of hazardous waste produced.

Hazardous materials cannot be diluted with a material which is not a waste
(water, for example) in order to bring them to concentration suitable for drain
disposal.  If you have questions, consult the Chemical Safety Manual or call
Safety Services (x2907).


Moving?  What To Do

Many researchers are moving from one part of the campus to another.  While
setting up the new lab to meet your tasks is important, it is also important
that the old lab is left in a condition suitable for other uses. Below is a list of
some of the items that must be completed in the lab you are moving out of
both before and after you move.

NOTE:  researchers moving off campus have additional requirements.  If you
are moving off campus, or if you would like further information, call
DOES(x2906).

Before the Move

If your lab uses radioactive materials:

All radioactive waste must be disposed of.

The lab and all its equipment must be surveyed and the results recorded,
since these results are checked by the Radiation Safety Office before the move. 

For Safety Services to give its approval for the move:
  
All chemical waste must be disposed of.

All sharps or biohazards must be removed.

An updated chemical inventory (those chemicals that are going with the
researcher) should be submitted.

A Right-To-Know session must be given to the contractor assisting in the
move.


After the Move

Your old lab space must be decommissioned.  If you used radioactive
materials, the survey results will be confirmed by the RSOF.

When given permission from DOES, remove all signs and labels.  Place
new signs and labels in applicable places in your new lab.

Submit a new chemical inventory list, whether or not there are any
changes.


Peroxide Formation in Ether

Ethyl ether is a potentially dangerous chemical because of its anesthetic and
flammable properties.  An additional danger comes from the peroxides that
can form from residual amounts of ether left standing in closed containers.
Explosions from peroxide formations are rare; however, knowledge of the
hazardous properties of ethers and the special problems of peroxide
formation in ether can contribute even more towards prevention.

General Hazardous Properties of Ether

Because of their high vapor pressures, ethers pose a particularly
dangerous fire hazard and may ignite at only a 1% concentration laboratory
air.

The explosive and flammable nature of ethers increases with heating.

Ethyl and isopropyl ethers are powerful narcotics which can cause
unconsciousness and death upon acute exposure.

Ethers react violently with strong oxidizing agents such as sulfuric, nitric
and perchloric acids and may explode upon mixing.

Peroxide Formation in Ether

Peroxides form in the air above contained sources of ether, and formation
occurs easiest when large volumes of air come into contact with residual
sources of ethyl ether.  Thus, ether containers with only a few milliliters
remaining are especially prone to peroxide formation.

Peroxide formation is a slow oxidative decomposition that generally takes
several months in stabilized ethers; however, peroxides may form in freshly
distilled and unstabilized ethers within less than two weeks.

Upon formation of peroxides, ethers can become friction-sensitive, shock
sensitive, and heat sensitive, making detonation from any of these possible.

Isopropyl ether seems unusually susceptible to peroxidation.  


Use, Storage and Disposal of Ethers

Use a fume hood for all transfers and reactions with ethers.  Store ethers in a
dark place since exposure to light contributes to peroxide formation.

Prompt disposal of small quantities of ether will minimize the hazardous
formation of peroxides. Disposal should include an effort to note the date
when the bottle was opened.   All containers of ethers come with an
expiration date; use or dispose of ethers before this time.


Finding the Right Meter for the Job

It is imperative when working with radiation that you monitor  for 
contamination.   However, there are several types of meters available for this. 
You must be certain that the meter  you choose is designed to monitor the
type of radiation with which you are working.  You must also use these
meters correctly so that they sufficiently protect you.

Types of Meters

Most of the meters used at CWRU laboratories are Ludlum  meters and are
one of three types:

Model 44-9, or the pancake Geiger-Mueller probe:  used for detecting beta
particles such as P32, C14, and S35.   It can also detect I125 emissions, but the
efficiency is extremely low.

Model 44-3, or the sodium iodide probe:  used for detecting gamma
radiation such as I125 emissions.  The sodium iodide probe cannot detect
other kinds of radiation well, so use this probe if you work with gamma
emitters only and have no need to measure other isotopes.

Model 44-21, or the sandwich probe:  used for detecting all types of
radiation isotopes, P32, C14, S35 and I125.  It is specifically designed to pick up
both beta and gamma emitters  and is therefore the most universal in its
detection.

How They Work

Again, finding the right meter is only the first step in efficiently monitoring
radiation.  The meter can only work efficiently if the cap if OFF.   In fact, when
you have your meter calibrated by the Radiation Safety Office, the efficiencies
are calculated with a bare probe - no cap, or even parafilm.  Why?  Because
beta radiation-particularly weak emitters such as C14 and S35-are partially or
completely shielded by the plastic of the cap.  They never reach the detector,
and so they do not register on the meter.  You could be passing up major
contamination problems and never know it until someone meters properly.

If you use a combination of beta and gamma emitting isotopes in your lab, the
best thing to do is always leave the cap OFF when using your meter.  If you
find contamination and you aren't certain which isotope it is, THEN put the
cap on.  If the reading is unaffected, it is probably a gamma emitter such as
I125, though P32 will only be partially shielded.  If you only use beta emitters,
you should NEVER meter with the cap on.  Just be careful to avoid
contaminating the probe.

What and When to Monitor

Leave the meter on throughout the experiment as well as monitoring
afterwards.  Monitor your gloves several times throughout the experiment
and don't forget to monitor your shoes, especially the shoe bottoms, before
you leave the work area to avoid spreading radioactive contamination.

Tritium, remember, cannot be detected with any of these probes.

The above model numbers are specific to Ludlum probes.  Different brands
will use different model numbers, but the principles are the same.  Call the
Radiation Safety Office at x2906 if you have any questions concerning the
above information.  Monitoring  radiation is effective only if done correctly.


Safety With Corrosive Materials

A corrosive material is defined as a chemical whose action will result in an
immediate, acute erosive effect on bodily tissues as well as other substances. 
Though they are common in many laboratories, extreme care must be taken
when working with these sorts of chemicals because they represent a hazard
in several ways-through direct contact with the skin or eyes, through skin or
eyes, through breathing or through ingestion.

Corrosive chemical liquids such as mineral acids, alkali solutions, and certain
oxidizers, are especially dangerous to the skin and eyes because splashes so
easily occur when working with them.  Corrosive gases and vapors affect all
parts of the body, though the eyes and respiratory tract are most susceptible to
damage.  Highly soluble gases such as ammonia or hydrogen chloride
severely irritate the nose and throat, while less soluble materials like nitrogen
dioxide phosgene, sulfur dioxide can penetrate further into the lungs.

Safe work practices in laboratory settings  are explained in the CWRU Safety
Manual, from which labs can create their Chemical Hygiene Plan (as required
by OSHA).  In addition to these general safety precautions, the following
should be adhered to when working with corrosives.

Corrosive Chemical Liquids

Wear proper face and eye protection.  Accidental splashing occurs
frequently, and eyes are extremely vulnerable to danger.

Wear gloves and other chemically resistant protective clothing to prevent
skin contact.

Flash steam explosions can occur from mixing acids and bases, as large
amounts of heat form at the liquids' interface.  To prevent these steam
explosions, always add acid and bases to water and not the other way around.

Store acids and bases separately in the lab.

Store liquid corrosives below eye level.

Have adequate spill control ready in case an accident occurs.

Corrosive Gases and Vapors

Use a fume hood when working with chemicals that may be harmful if
inhaled, or wear other appropriate respiratory protection.

Protect all skin surfaces from contact with corrosive gases or vapors.

Remember that warning signs such as odor or eye, nose or respiratory
tract irritation  may be inadequate with some substances.  They should not be
relied upon as a warning of overexposure.


Awareness of the danger of corrosives materials  is the first step in safe lab
practice, so exercise the proper precautions when working with these
materials.  If  you are unsure of a chemical's hazard, call the Department of
Occupational and Environmental Safety (DOES) at x2907.


Waste Disposal Tags

Recently an article in the newsletter asked that waste amounts be listed in
percentage concentration when filling out the waste disposal tag.  However,
the computer system we currently use requires that amounts be listed using
the metric system.  Therefore, we ask that you please convert percentages to
liters or kilograms and write those amounts on the waste disposal tag.  We
apologize for the inconveniece this has caused some of you, and if you have
further questions on the necessary procedure, please do not hesitiate to call
Safety Services (x2907).


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