SOP Preparing a 20L 1%HF and 1% HNO3 acid mixture #4 Engineering / Ventilation Controls #5 Special Handling Procedures and Storage Requirements

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1 Standard Operating Procedure (SOP) for preparing a 20L (5 gl) 1% Hydrofluoric (HF) and 1% Nitric (HNO3) acid mixture for use in canisters in the Ultrasonic bath #1 General Process Description Creating the acid mixture that is used for etching/cleaning your quartz sample. All work described in this SOP will have to conducted in Mitchell A20. Contact Principal Investigator (PI): Prof. George E. Hilley for more information (hilley@pangea.stanford.edu or (650) ). This SOP is from 05/04/2007. #2 Hazardous Chemicals/Class of Hazardous Chemicals In order to create an acid that is capable of etching quartz, you will have to use Hydrofluoric acid (HF). Concentrated Hydrofluoric acid is one of the most corrosive and dangerous chemicals encountered in the laboratory. HF can cause severe tissue damage and even death. However, we are only using concentrated HF in the fumehood and a much more diluted version outside of the fumehood. We will be using: ~400mL of concentrated (49%) Hydrofluoric Acid (HF) and ~300mL of concentrated (~70%) nitric acid (HNO3) to produce a 1% HF-HNO3 mixture with a total volume of 20L. #3 Personal Protective Equipment (PPE) Before any acid is taken out of the acid-storage cabinets, ensure that you will at least meet the following protective requirements: 1. goggles (prescription glasses are not enough!) 2. (double glove neoprene) 3. closed-toe shoes with socks 4. long pants (no shorts!) 5. lab coat 6. face shield 7. neoprene apron 8. small Chemical Spill Kit

2 All Material Safety Data Sheets (MSDS) are located in the red folder in the storage cabinet opposite of the dishwasher under the vertical laminar flow unit. Ensure the Calcium Gluconate is not expired and is available in the event of an exposure. The Calcium Gluconate is stored below the sink right next to the entrance door and in the closet above the sink right next to the entrance door. #4 Engineering / Ventilation Controls All work with concentrated acids has to be done in the fume hood with the protective shield drawn down as much as possible, but allowing to work comfortable. Make sure that you place the 20L canister that you are filling up far enough inside the fume hood. #5 Special Handling Procedures and Storage Requirements Store all Hydrofluoric Acid and HF waste in labeled chemically compatible containers (e.g., polyethylene or Teflon). Do not store in glass, metal, and ceramic containers, as they are not compatible with HF. Store all concentrated Hydrofluoric acid containers in the acid cabinets in its proper secondary containment tray. Hydrofluoric acid is stored in the acid cabinets under the fumehood, right bottom shelf. Place a secondary containment tray in the fumehood, when handling and pouring concentrated acids. In case you overfill or spill acids, it will stay in this secondary containment. Also, the 20L acid mixture bottle will stay always in its secondary containment, unless it is being used for filling the 4L canisters. Transport the 20L acid mixture only on the cart and only in its secondary containment tray. Place the 1% acid mixture in its secondary containment at its dedicated space near the oven and telephone. Remember to slowly pour acid into water, never water into acid. No rinseates with ph below 5.5 may be drain disposed. 2

3 Please review the last page for emergency contact and notifications. #6 Spill and Accident Procedures If you spill acid and the spill is an immediate threat to your health, call Remain nearby. In the event of an HF exposure, follow Stanford University Hydrofluoric Acid First Aid Instructions posted in Mitchell A20. If you accidentally spilled concentrated Hydrofluoric acid (e.g., while pouring HF into the measuring cylinder): Don t panic! Remain calm. If the spill is small (less than a few ml up to 30mL), place a pads from small spill kit over the spill. Find a plastic/neoprene-disposal bag in the shelf above the scales and carefully place the soaked pads into the bag, and place in container provided with kit. To minimize contact with HF during clean-up, use Teflon tongs to move the soaked pads into the bag. All of this must be done in the fumehood. If the spill is significant larger (> 0.5L) or you flipped over an entire bottle of HF, use the yellow spill-containment pads under the sink by the door. Place them over the spill. If spill is greater than 30 ml, or cleanup takes longer than 15 minutes, document the cleanup activity either by calling EH&S at or by notating the lab inspection forms. IF THE CONCENTRATED ACID IS RUNNING OUT OF THE FUMEHOOD, place spill-containment pads on the spill and contact EH&S at immediately and leave the laboratory, but stay nearby to provide information to responders. DO NOT TRY to place the soaked pads into the neoprene bags, as fume evaporating from the concentrated HF pose a serious health hazard. Contact Bodo Bookhagen at or (415) and George Hilley at after you ve informed EH&S. If you have spilled parts of the 1% acid mixture, carefully wipe it off with small spill kit pads or soak it up with the yellow spillcontainment pads. Rinse the area with plenty of water, collect rinseate, and wipe off afterwards. To confirm that cleanup is complete, wipe area with moistened ph paper. 3

4 #7 Waste Disposal If you ve spilled acid and soaked up acid containment bags, make sure they are in disposable neoprene bags placed into the container provided by EH&S These containers will be labeled with an EH&S label and disposed separately. #8 Training requirements Prior to entering and working in the laboratory, you must have completed the EHS-4200 General Safety Training and EHS-1900 Chemical Lab Safety. You will have to retain training documentation for at least one year. Any person conducting work in Mitchell A20 using this SOP must receive training on the contents of this SOP. #9 Approval Required All research staff must get initial PI approval prior to starting work with Hydrofluoric Acid. Under no circumstances it is allowed to work with concentrated HF, while being alone in the laboratory. Always ask a second person to be in the lab with you. If you have to work with concentrated HF and you are alone, you have to ask for approval from the PI, Prof. George E. Hilley. #10 Decontamination All glassware and measuring cylinders that have been used during the process of mixing the 20L acid mixture should be thoroughly rinsed with DI water (3 times) and then with Millipore water (1 time). Collect first rinseate as hazardous waste. #11 Designated Area Concentrated HF is only allowed to be handled in the fumehoods. Filling and rinsing of the 4L canisters should only be done near a sink, but with secondary containment tray in sink. Upon leaving a designated work area, remove any personal protective equipment worn and wash hands, forearms, face, and neck. After each use (or day), wipe down the immediate work area and equipment to prevent accumulation of chemical residue. At the end of each project, thoroughly 4

5 decontaminate the designated area before resuming normal laboratory work in the area. 5

6 #12 Precise Process Description 1. Verify that emergency eyewash/shower is accessible and tested within last month. 2. Verify that fume hoods are currently certified. 3. Check the location and expiration of the Calcium Gluconate and that a copy of the MSDS for HF is available 4. Ensure that the spigot of the 20L carboy is tightly screwed on and that the carboy is emptied completely. 5. Turn on the Milli-Q filter machine and fill the carboy with milli-q water up to the 19L mark. 6. Add 300mL Milli-Q water with the glass measuring cylinder. 7. It is essential that you wear a face shield over your safety glasses, double neoprene gloves, and the neoprene aprons to ensure proper protection for concentrated acid spills. 8. FUMEHOOD: Place the carboy in its large, secondary containment tray. 9. FUMEHOOD: Place a medium, secondary containment tray in the fume hood and add 400mL hydrofluoric acid (HF) using the polypropylene 500mL measuring cylinder while working over the secondary containment tray. 10. FUMEHOOD: Add 300mL Nitric Acid (HNO3) using the glass measuring cylinder. 11. FUMEHOOD: Close the carboy and ensure that all spigots are closed. Gently swirl and shake several times to extensively mix the acids and water. Ensure that no inverting of container occurs. 12. Place the carboy and its secondary containment tray onto the cart and move it back to its dedicated position. 6

7 13. Wash the measuring cylinders, rinse them 3 x with Milli-Q water, and collect first wash as hazardous waste. 7

8 Laboratory Spill Response Procedures Health Threatening Situation - In the event of an imminent or actual health-threatening emergency (threatening local or public health, safety, or welfare; or the environment outside the immediate area): 1) CALL FOR THE FIRE DEPARTMENT REMAIN IN THE AREA TO ADVISE RESPONDERS. 2) ACTIVATE LOCAL ALARM SYSTEMS 3) Once personal safety is established, call EH&S at and proceed with local notifications, below. Non-Health Threatening Situation In the event of a spill or release which may or has impacted the environment (storm drain, soil, air outside the building) or spill or release that cannot be cleaned up by local personnel: 1) Notify Stanford Responders: call (24 hours/day, 7 days/week), then 2) Provide local notifications: Name Phone Number Cell or Pager Title George E. Hilley Principal Investigator Bodo Bookhagen (415) Lab Manager Felicia Morales Lab Safety Coordinator Local Response Situation In the event of a minor spill or release that can be cleaned up by local personnel using readily available equipment (absorbent, available from EH&S in Small Spill Kit): 1) Notify personnel in the area and restrict access. Eliminate all sources of ignition. 2) Wear gloves and protective eyewear. Clean up using absorbent. Put the contaminated absorbent in a labeled hazardous waste container. 3) If greater than 30 ml, or cleanup takes longer than 15 minutes, make a record in your lab inspection report, or call EH&S at to record the spill, and notify your supervisor. 4) Submit online waste pickup request to EH&S at: wastepickup.stanford.edu 8