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More detailed information on these topics are found in our various OSHA documents, including Safety Training Manual, MSDS, and CHP, all of which the employee must have been trained on.  This page is just a brief overview.

 

Liquid Nitrogen Safety

The storage room is clearly labeled.  It's only a temporary room until the remodel is done, and it does not have good ventilation.  Always leave the door to that room open to avoid build-up of nitrogen gas. Lids can be removed and levels checked without extra precautions because very little gas escapes.

 

Filling dewars requires extra precautions.  You may not perform a fill unless you have been fully trained and approved by your supervisor to perform this function.  Prop open the outside door to that room.  You must always wear eye protection and the cryogenic gloves when dispensing liquid nitrogen.  If liquid gets on clothing, hold it away from the body until dry.

 

Formaldehyde Safety

The permissible exposure limit (PEL) for formaldehyde in the workplace is 0.75 parts formaldehyde per million parts of air (0.75 ppm).  Formaldehyde monitoring has already been performed and the level was found to be lower than the 0.5 ppm action level.  Our tested levels were 0.03 ppm for 15 minutes, and lower than 0.03 ppm for 8 hours.  These exposure levels assumes that the procedures specified in this Manual are followed without deviation.

 

Symptoms of Exposure include stinging eyes and coughing.  If any of these symptoms are encountered, leave the fan on, close the cabinet door, and get a supervisor.  If splashed in the eye, there is an eyewash station in the next room.  If splashed on the skin, remove contaminated clothing and soak with a wet paper towel. 10% formalin splashed on the skin will not cause significant damage if removed quickly.  Any worker who develops signs or symptoms associated with formaldehyde exposure is provided an opportunity to receive an appropriate medical examination.

 

Aldehyde Waste

Liquid aldehyde waste is processed as follows.  First, estimate the quantity of liquid, rounding up slightly.  Then, calculate the amount of Formalex to use:

10% NBF (4% formaldehyde): 1:4

3% glutaraldehyde: 1:4

10% NBF + 3% glutaraldehyde: 1:2

For example, for 4 L of formalin, 1 L of Formalex will be needed.  Formalex is measured on the counter and does not require the same ventilation as the aldehydes.  Pour the Formalex and the waste into the container labeled "neutralized formalin waste".  Put a sticky note on it with your initials, the date, and "neutralized".  Leave it for at least 24 hours.  After waiting, pour it slowly into the utility sink with the water running, diluting with at least 10 times as much water as waste.  If there are any solids, pour it through the strainer, and place the solids in the red biohazard container, although they are not technically hazardous at this point.  Wipe and then wash the container.  Wash the graduated cylinders and set out to dry.