Phosphorus Pentoxide

This chemical standard operating procedure (SOP) is for your safety. Read, understand, and follow this document. If this is a paper copy, you should check for the most recent version on the IsoLab website. This document was created from a template modeled after the University of Washington Environmental Health and Safety Laboratory Safety Manual Standard Operating Procedures Components.

Is Phosphorus pentoxide a particularly hazardous substance? YES

What is a particularly hazardous substance? The University of Washington Environmental Health and Safety defines it here.

The SDS for Phosphorus pentoxide can be found here.

1. Process Phosphorus pentoxide is used with 85 % phosphoric acid to make >100% phosphoric acid for carbonate digestion and subsequent isotope analysis.
2. Hazards Phosphorus pentoxide (P2O5) reacts violently with water, causes severe skin burns and eye damage, and may cause respiratory irritation. Refer to the SDS for more information. Phosphorus pentoxide creates phosphoric acid on contact with water.
3. Personal Protective Equipment While working with P2O5 in a fume hood, you should be wearing nitrile gloves and a lab coat. Do not work with P2O5 outside of the fume hood or near water.
4. Environmental / Ventilation Controls P2O5 is to be used in one of the fume hoods in 303B or the fume hood in 302A. Ensure the fume hood has appropriate flow prior to working with P2O5. Do not work with P2O5 unless the fume hood is functioning properly.
5. Special Handling Procedures & Storage Requirements P2O5 is stored in the Corrosives Cabinet under the fume hood in 302A. Make sure you have gloves on before grabbing the reagent bottle. P2O5 it is extremely hydrophilic so close the container tightly and quickly with the appropriate lid when not in use.
6. Spill and Accident Procedures

All personnel without PPE should leave the room if there is a large spill outside of the fume hood. Dust may present an irritation. The spilled powder will heat up as it absorbs water from the atmosphere.

Use personal protective equipment. If spill is outside of fume hood, don a respiratory mask located in 303B near the balances in addition to a laboratory coat, nitrile gloves, and goggles. Avoid dust formation. Avoid breathing dust. Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment should be avoided. Pick up and arrange disposal without creating dust. Sweep up and shovel. Keep in suitable, closed containers for disposal.

If you need further assistance, during business hours, call EH&S at 206.543.0467 or if after hours, call 911 and ask for EH&S assistance. When necessary EH&S will obtain a chemical spill cleanup contractor at the lab’s expense.

Spill materials are a hazardous waste. Report the spill via the EH&S Online Accident Reporting System (OARS).

If the spill occurred in and is completely contained in the fume hood, clean up all material using wipes and paper towels. Discard all materials that have come into contact with P2O5 into the designated waste container.

7. Waste Disposal All P2O5 waste is contained in an appropriate labeled tightly sealable plastic, wide-mouth, container. Do not open the waste container unless it is contained in a fume hood. Excessively soiled wipes used for cleanup, must go into the waste container. Contact EH&S for waste removal when the container is sufficiently full or aged.
8. Special Precautions for Animal Use (if applicable) N/A
Particularly hazardous substance involved? YES, see 9-11
9. Approval Required You should have taken Managing Laboratory Chemicals or similar UW EH&S condoned course before using P2O5. You must have read and understood the SDS for P2O5 as well as this SOP.
10. Decontamination Make sure all P2O5 has been cleaned up and contained in appropriate containers before moving away from the fume hood. Ensure all utensils and trays have been wiped clean before removing them from the fume hood.
11. Designated Area P2O5 may be handled in the fume hoods in 303B or the fume hood in 302A.


I have read and understood this Chemical SOP:

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Last updated: 2020-10-13 11:36:47