March 1994

Formaldehyde and Air Monitoring

Since 1992, the year that new OSHA formaldehyde standards went into effect,
much emphasis has been placed on monitoring the levels of formaldehyde to
which researchers may be exposed.  The Department of Occupational and
Environmental Safety (DOES) has a formaldehyde monitoring program in
place to ensure safe limits are established in the laboratory.

The OSHA standard applies to formaldehyde gas and all mixtures or
solutions composed of greater that 0.1% formaldehyde.  It also applies to all
materials capable of releasing formaldehyde into the air at concentrations
reaching or exceeding 0.1ppm.

The limits set in 1992 are as follows:  the Permissible Exposure Limit (PEL) is
0.75ppm/8hr. average.  The Short Term Exposure Limit (STEL-the peak
exposure acceptable in one fifteen minute period) is 2.0ppm, and the Action
Limit (the level at which precautionary action must be taken) is 0.5ppm/8hr.
average.  It is important to realize that the odor threshold of formaldehyde for
most people is 0.8-1.0ppm.  This means that formaldehyde levels may exceed
the PEL even though you do not smell anything-odor is not a reliable
indicator of compliance with OSHA limits.

Researchers who use formaldehyde without a fume hood (even if only
occasionally) should have filled out a questionnaire last year stating this
information.  Based on the information given-how often you use
formaldehyde, under what conditions-one of our safety technicians will
ascertain if and when monitoring is needed.  If it is, the technician will
contact you to set up a date.

Air monitoring takes place for the length of the procedure or 8 hours,
whichever comes first.  If OSHA limits are not exceeded, no further
monitoring will be necessary for another year unless a change in personnel,
process, control measures, or equipment occurs.  Contact DOES under these
circumstances to set up a monitoring session.

If, during air monitoring, OSHA limits are exceeded, action must be taken.  If
the PEL or STEL is exceeded, the process must stop until proper engineering
controls and personal protective equipment (PPE) are put in place.  If the
Action Limit is exceeded, the engineering controls in place (a fume hood, for
example) must be checked and adjusted.  The process itself, unlike with PEL
or STEL limits, does not necessarily have to be changed.  Air monitoring will
continue until results from two consecutive sampling periods taken at least 7
days apart show that safety levels are being met.

Labeling of formaldehyde is stringent.  All materials capable of releasing
formaldehyde must be identified and labeled.  If the solution contains 0.1%
formaldehyde or if it is capable of releasing 0.1ppm formaldehyde, a label
must be in place saying:  "DANGER:  Contains Formaldehyde:  Irritant and
Potential Cancer Hazard" (available from our office).  In addition, a written
communication program for exposure should be placed in each lab.

Specific training in formaldehyde is required by the standard for all
employees working with or having the potential of being exposed to
formaldehyde.  Formaldehyde training is included in the OSHA Lab Standard
Training sessions offered by DOES.  Call us (x2907)  if you need to set up a
monitoring session.


Sorting Out Laboratory Waste

Decreasing landfill space and new landfill laws makes waste disposal a tricky
business, especially for producers like CWRU:  diverse types of waste and lots
of it.  Waste generated at CWRU-from "sharps" to notebook paper-must be
carefully segregated in order to ensure disposal in an environmentally sound
way.

Basically, there are two avenues for waste disposal:  contaminated or
biohazardous waste, disposed of in red biohazardous containers, either in
rigid boxes if it is "sharp" or bags if not, and uncontaminated lab waste, to be
disposed of in black bags.  A fuller explanation of what goes where in the
world of waste is given below.

SHARPS:  hypodermic needles, syringes, scalpels, cannulas,
microscope slides, coverslips, broken glass, razor blades, and all pipettes.

All sharps must be disposed of in puncture-proof containers. Contaminated
sharps must be disposed of in a red, rigid, plastic SHARPS container.  All
discarded hypodermic needles, syringes, cannulas and scalpels, whether or
not they are contaminated, must also be disposed of in a red, rigid, plastic
SHARPS container.  

All other perceived sharps that are not contaminated-microscope slides,
coverslips, broken glass, pipettes, or any other item which may cause a
puncture wound or cut-may be disposed of in a puncture-proof cardboard box. 
This box must clearly be labeled "SHARPS" so that everyone is aware of the
contents.

For pick-up of non-radioactive sharps call the Biohazard Pick-up line (x6906)
before 4:00 for an evening pick-up.  For pick-up of radioactive sharps, call the
Radiation Safety Office (x2906).

BIOHAZARDOUS WASTE:   all non-sharp infectious waste such as
plastic petri plates; plastic tissue culture vessels containing media, cultures
and stocks of infectious agents; devices used to transfer, inoculate or mix such
agents; and paper or cloth material contaminated with these agents.

All waste of this sort must be sterilized prior to disposal.  Each researcher is
responsible for treating waste as close to the point and time of waste
generation as possible.

Biohazardous waste must be autoclaved in red bags labeled with the
international biohazard symbol.  After sterilization is complete, mark
"Sterilized" on the bag and tag it with the Investigator's name and the date of
sterilization.  These bags must remain in the lab for pick-up.

Call the Biohazard Pick-up line (x6906) before 4:00 for an evening pick-up.  

UNCONTAMINATED LABORATORY  WASTE:  all other
laboratory waste that has not been contaminated by radioactive, chemical or
infectious agents such as petri plates, paper cloths, gloves, tubing, non-sharp
lab wastes, empty chemical containers, as well as "ordinary trash" like
packaging materials (such as empty Fisher pipette containers) and cardboard.

This waste should be disposed of in black bags and can go out as general trash
to be picked up by the custodial staff.

Recyclable goods such as paper and glass, cans and plastics should be disposed
of in specially marked green or blue bins. 

Previously, ordinary trash had to be placed in separate clear bags.  Now this is
no longer necessary-ALL general uncontaminated laboratory waste can be
disposed of together in black bags.  Questions concerning proper disposal
should be addressed immediately- call the Department of Occupational and
Environmental Safety (x2907) with any specific needs or problems.  It is vital
that waste at its source-in the lab-be properly prepared for disposal.


Picric Acid:  A Serious Explosive

Picric acid solutions are frequently used in campus research and clinical
procedures for making tissue fixatives, organic synthesis, and some protein
work.  In solution, picric acid is relatively safe.  When picric acid is dry,
however, it becomes a shock-sensitive, unstable compound with more
explosive force than dynamite.  Extreme care should therefore be taken when
handling potentially dangerous picric acid. Keep the following guidelines in
mind:

Never let picric acid crystallize and never open a source of picric acid that
you suspect is dehydrated.  Just the friction from unscrewing a cap is enough
to detonate picrate crystals in the cap threads.

Never heat picric acid to or near dryness.  Its shock-sensitive properties
increase with heating and it will spontaneously explode.  

Picric acid will form highly explosive picrate salts upon mixture with lead
or zinc metals and nitric acid.

If you find an old container of dry picric acid with a metal cap, do not
touch it!   Metal picrate salts may form as the acid corrodes the metal cap over
time, and some metal picrate salts are even more shock-sensitive than the
acid form.  Removal and disposal of such containers is a job for the bomb
squad, literally.

When ordering picric acid, purchase solutions instead of the wetted paste
whenever possible.

Finally, picric acid is a toxic compound and should be handled with
gloves.


Picric acid in its shock-sensitive condition looks and acts like dry sand; its 
dangerous explosive properties are evident only in its dehydrated crystalline
form.  Picric acid should contain at least 15% water by weight; if you suspect a
container of picric acid is too dry, call the Department of Occupational and
Environmental Safety (x2907) and we will come inspect it.  Please do not try to
dispose, hydrate, or otherwise take care of it yourself.


Disposal of Radioactive Waste in the Sanitary Sewer

All laboratories are permitted to dispose trace quantities of radioactive
materials down the sanitary sewers provided that the radioactive solution is
not classified as a regulated waste by the EPA.  Prior sewer disposal criteria by
the NRC demanded that radioactive material be "soluble" and "readily
dispersible," and that the disposed material met all other Federal, State, and
local sewer disposal criteria. 

With the enactment of new NRC regulations (effective Jan. 1, 1994) the
definition for " sewer disposable materials" has been changed.  The
radioactive material constituent must be soluble or be a readily dispersible
biological material.  In addition, the regulations restrict sewer concentrations
based on the chemical form of radioisotope.

Since January 1993, in anticipation of these changes, the Radiation Safety
Office has required that researchers list the chemical form of the isotopes in
aqueous solutions we pick up for decay in storage.  For those labs that dispose
of radioactive materials down the sanitary sewer, the sewer disposal waste
logs should include the chemical form of the isotope (i.e. dATP) in addition
to the date, isotope, and activity of the disposal.  

In most labs on campus, the radioactive material being disposed down
sanitary sewers is already dissolved in aqueous solutions or incorporated into
tissue culture cells, meeting the criteria of the new regulation.  Therefore,
besides having to record the chemical form of the radiolabeled compound,
the Radiation Safety Office does not anticipate any major changes to the 
sewer disposal habits of labs based on the new ruling.  

A notice containing details and a sample disposal log will be mailed to
radioactive materials users in the near future. 


Vial Control

The Radiation Safety Office has observed ongoing problems with scintillation
vials during waste pickup.  Below are some guidelines to proper  vial disposal
to prevent leakage and to ensure safety for all involved.

Use only the appropriate bag for disposing vials--the bags we give out for
dry waste are inappropriate for disposing vials.

Vials should be double bagged to control leakage.

Vial bags should not be overfilled--use a number of small bags rather
than one overfilled bag.  

They should not contain anything but vials--no gloves, paper, pipette
tips, tissue trays, etc.

Scintillation fluid does not need to be separated from the vial itself before
disposal; the entire vial (cocktail included) can simply be thrown away.


Leaking vial bags will NOT be picked up by Radiation Safety technicians. A
contamination hazard is present for all involved, and we will not risk the
massive cross contamination that can occur in these situations.  The
Radiation Safety Office has small, thick-walled vial bags available for free.  If
you need some, call us at x2906.


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