Safety Moments Topic: Chemical and Compressed Gas Safety A Safety Moment is a brief safety talk about a specific subject at the beginning of a meeting or shift. Also known as safety minutes or safety chats, these talks can be done in a variety of ways, but are typically a brief (2-5 minute) discussion on a safety related topic. They can cover a variety of safety topics and remind employees of the importance of being safe; at work, at home and in all aspects of our lives. Use one slide per Safety Moment (unless specified).

Reducing Explosion Hazards If your work area contains explosive devices, reactive chemicals or pressure vessels, the risk of explosion exists. Prevention begins with understanding what materials in the workplace can explode the factors that can trigger an explosion. Keep explosives from heat. Use only approved storage and transfer containers. Make sure containers are grounded and bonded before transferring flammable liquids. Report equipment malfunctions immediately. Make sure ventilation equipment is working properly. Monitor the air when using explosive materials in confined spaces. Read your safety data sheets. They’ll tell you if a substance can explode and what to do if something goes wrong. The key words— FLASH POINT and FLAMMABILITY LIMITS- tell you the chemical’s safe- ty levels. Be alert to any changes in temperature or pressure that could mean a change in explosion risk.

Working with H2S What is H2S? Colorless (transparent) gas Heavier than air and tends to accumulate in low-lying areas POISONOUS = PARALYZE THE BREATHING SYSTEM/CAN KILL IN MINUTES!!!!!!!! Highly toxic and Very corrosive Rotten Egg – smell The immediately dangerous to life or health limit is 100ppm or above! If you are working with H2S ensure you have the proper monitors, engineering controls and PPE! Contact HWCOE Safety www.jst.umn.edu

Peroxide Forming Chemicals “Lesson Learned” from University of California Irvine 2006 <http://www.ehs.uci.edu/salerts/Lesson%20Learned_Peroxide.pdf Peroxide Forming Chemicals Explosion was partially contained in water bath, residue visible on rotovap glassware Ether safety overview: Ether can form peroxides when exposed to air Peroxides are shock-sensitive explosion hazards To minimize risks: Purchase what will be used within the month Purchase Ethyl Ether that contains peroxide inhibitors such as BHT or ethanol Store away from heat and light Test for peroxide formation monthly after expiration Many solvents can form shock-sensitive peroxides over time Diethyl ether Isopropyl alcohol THF Friction, shock, or concentration can cause an explosion Graduate student at UC-Irvine sustained cuts from exploding glassware while concentrating diethyl ether

Pd/ C Hydrogenations (side 1 of 3) Danger comes from the active catalysts Absorb hydrogen gas Can spark spontaneously and may ignite on exposure to air Readily causes ignition of flammable solvents in the presence of air. Use in presence of H2 gas, sometimes at high pressure and temp. In the event of fire, contain it with water Types of Catalysts Degussa – safest Wet – safer. Higher % of water Dry Do not operate near flammable materials Perry, David. Hazards in Hydrogenation. http://chemicalspace.wordpress.com/2010/07/27/hazards-in-hydrogenation/

Pd/ C Hydrogenations (slide 2 of 3) Correctly done, these reactions can be routinely run safely Weigh and add catalyst first Flush vessel with nitrogen. Handle Pd/C under inert atmosphere. Add solvent. (Degas solvent with large scale > 100 mL) Use ethanol, not methanol (very flammable, invisible flame) Flush reaction vessel with N2 , run reaction, repeat flush with N2 Remove Pd/C through filtration (celite on glass frit), and cover with wet sand. Filter cake should never be allowed to dry, and the moist material should be added to a large quantity of water and disposed of properly. Dispose of waste in dedicated container that contains water. Know how to use the equipment Don’t over-pressurize Don’t use damaged equipment or glassware. Prudent Practices in the Laboratory: Handling and Disposal of Chemicals Laboratory Chemical Safety Summary: Palladium on Carbon

palladium on carbon catalysts Pd/C (slide 3 of 3) According to Prudent Practices in the Laboratory, palladium on carbon catalysts containing adsorbed hydrogen are pyrophoric, particularly when dry and may ignite on exposure to air

MSDS vs. SDS Material Safety Data Sheet vs. Safety Data Sheet “Hazard Communication Standard has been revised by OSHA to align with the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)” There were many acceptable MSDS formats Now the GHS format has 16 sections in a set order (very similar to the ANSI Standard 16 section MSDS commonly used in the U.S.) Visit MSDSonline.come to see an ordered list of sections Expect to get a mixture of MSDS and SDS formats from manufacturer until transition complete Dec. 1, 2013- employees trained to read SDS and GHS labels June 1, 2015- chemical manufacturers/distributors start shipping with only GHS format Dec. 1, 2015- only GHS formats shipped June 1, 2016- Employees fully compliant with HazCom 2012 (Hazard Communication revised 2012, new OSHA standards) EHS offers training w/ the GHS update through the following trainings: UF_EHS814_ILT, UF_EHS847_ILT, UF_EHS862_ILT

HF Safety (slide 1 of 4) HYDROFLUORIC ACID IS one of the MOST ACUTELY TOXIC CHEMICALS There is no concentration of HF which can be relied upon as safe! As little as 7 ml of anhydrous HF in contact with the skin untreated can bind all the free calcium in an adult With burns involving greater than 25 square inches significant and sometimes fatal hypocalcaemia can occur There is no material that is completely resistant to HF degradation

HF Safety (slide 2 of 4) PROPERTIES Colorless liquid with strong irritating odor Very strong corrosive inorganic acid Nonflammable How Is HF Different from other acids? HF is readily absorbed into skin binding to calcium and magnesium in the body to form insoluble salts that interfere with cellular metabolism causing cellular death and necrosis Immediate necrosis and pain at high concentrations Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.

HF Safety (slide 3 of 4) EXPOSURE Liquid exposure (splash) Gas exposure (lungs, skin & eyes) Severe burns Opacification of cornea Blindness Coughing/Choking Cyanosis (blue lips) Worker Airborne Exposure Regulations Irritation to nose and throat at 3 ppm Short-term exposure limit 15 min - 2 ppm 30 ppm is considered immediately dangerous to life and health Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.

HF Safety (4 of 4) PPE SAFE WORK PRACTICES Never use HF alone Training Always Wear Personal Protective Equipment Documentation & Signs Always use HF in the lab hood PPE Neoprene gloves (Resistant for more than 8 hours) Saranex coated coveralls Face shield Foot protection Baird D. and Cooper C., “Hydrofluoric Acid Safety”, Fermilab.

Responding to Chemical Burns (slide 1 of 2) The following chemical groups; commonly used in industry and in the home, cause chemical burns: reducing agents such as sodium, potassium and lithium used in metal cleansers and soldering processes; strong acids such as sulfuric, muriatic, tannic and hydrofluoric acid; bleaching agents and strong ba- ses such as lye. Chemical burns are different from heat burns in two ways: They usually produce no heat though the victim may feel a burning sensation and they go on burning until every bit of the chemical is removed. This is due to the fact that chemical reacts with body tissue to cause the burn. The longer the chemical remains on the body, the deeper the burn. Conse- quently, treating a chemical burn is a race with time.

Responding to Chemical Burns (slide 2 of 2) When you are dealing with a chemical burn, your top priority is to get under running water as fast as possible and stay there for at least 15 minutes. Clothing contaminated with the caustic chemical should be removed after you’re in the shower. If no shower is available, use tap water or a garden hose but remember that these water sources may not provide the best water pressure and should not be relied on if a shower is available. Seek medical attention! Call 9-1-1 if life threatening, or go to urgent care after flushing

Chemicals in Fridges and Freezers Use a refrigerator approved for storage of these materials Modified to not spark inside Approved for “flammable storage” The atmosphere of a refrigerator could contain an explosive mixture of air & chemical vapors To avoid inhaling vapors, don’t stick your head inside Seal containers tightly (parafilm or tape are good options) Store incompatible chemicals separately Oxidizers and highly reactive in a separate unit from flammables. Use secondary containment Air- and moisture- sensitive materials stored at low temp. are prone to problems exacerbated by condensation. http://www.tampabay.com/news/publicsafety/fire/refrigerator-blast-prompts-fire-alarm-at-usf/2168615

Safely Using Liquid Nitrogen It’s an inert, colorless, odorless, non-corrosive, non-flammable, and extremely cold It’s stored in cryogenic liquid cylinder with adequate ventilation Do NOT have any part of body come in contact with uninsulated pipes or equipment containing liquid nitrogen Extremely cold metal will cause the flesh to stick fast and tear when attempting to withdraw from it Containers should be handled and stored in upright position Do not drop, tip, or roll containers on their sides Required PPE: Safety glasses, Full face shield, Loose-fitting thermal insulated gloves, Lab coat, Long pants, Closed-toe shoes *This safety moment brought to you by the BME Student Safety Council*

Before using cylinders: Make sure the cylinder is equipped with the correct regulator.  Inspect the regulator and cylinder valves for grease, oil, dirt, and solvent. Never use grease or oil to lubricate regulators or cylinder valves because they can cause an explosion.  The cylinder should be placed so that the valve handle at the top is easily accessible.  When using toxic or irritating gas, the valve should only be opened while the cylinder is in a  working fume hood.  Only use wrenches or tools that are provided by the cylinder supplier to open or close a valve. Pliers should never be used to open a cylinder valve. Some regulators require washers; this should be checked before the regulator is fitted.  Refer to Safety Data Sheet [SDS] for the gas being used for information regarding use and toxicity.  Fire extinguishing equipment should be readily available when combustible materials can be  exposed to welding or cutting operations using compressed cylinder gases

Cylinder storage Compressed gas cylinder storage areas must be in a fire resistant enclosure located away from emergency exits and must be kept well-drained, well-ventilated, cool, and protected from the weather. Regardless of size, all cylinders shall be provided with supports (straps, chains, or other similar devices) capable of preventing the cylinders from falling.  Under no Condition shall the temperature of gas cylinders exceed 50°(125°F). When Type E gas cylinders are being not exceed 34°C (93°F) since the relief valves of Type E cylinders are set to release above 35°C.  Excessive storage time shall be prevented by the use of the smallest practical size cylinder for a particular gas application.  Corrosive gases shall not be stored for more than six (6) months. Usually after this period of time, there is a deterioration of the gas purity which increases the possibility of cylinder valve malfunction.  Oxygen or nitrous oxide shall not be stored in the same area with flammable gases unless separated by at least 20 feet or by a one-hour rated fire resistant partition. Cylinders stored in an area outside a building must be a minimum distance of 20 feet from flammable gases or combustible material.  All storage rooms that contain in excess of 2000 cubic feet of oxygen and/or nitrous oxide shall be vented to the outside.

Transportation of cylinders Only personnel of sufficient physical stature and strength are physically to move gas cylinders so as to minimize any potential hazard resulting from the size and weight of the cylinders.  When cylinders are moved, they shall be disconnected from any regulators or manifolds, and where threaded to accept protective valve caps, the valve caps shall be secured in place before the cylinders are released from their securing device. Cylinders shall be moved only on a hand truck or other cart designed for handling gas cylinders.  No more than one cylinder shall be handled at a time except on carts designed to transport more than one cylinder.

Compressed gas safety - regulators https://www.swagelok.com/en/Resources/Videos/Our_Tech_Tip_Videos/Component_Assembly_Tips/PTFE%20Tape%20application%20video