Chapter 3: Understanding and Communicating About Laboratory Hazards

1. Chapter 3: Understanding and Communicating About Laboratory Hazards Section 3.1.1 Responding to Laboratory Emergencies Incident 3.1.1.1 Reusing Gloves How We Become Exposed to Hazards Hazard = potential source of danger or harm (can’t eliminate) Exposure = coming into direct contact with a hazard (try to minimize) i. Route of chemical exposures: contact with skin ii. Routes of physical hazard exposure: hit by flying particle from an explosion

2. Routes of Chemical Exposure Ingestion (Oral route): swallowing hazardous chemical To be toxic, the chemical must be absorbed in the stomach or intestines Avoidance is straightforward • Don’t Eat or Drink in the Lab • Don’t Taste the Chemicals! (Chemists used to do this for analysis) Accidental ingestion can occur by contaminated objects (hand, pen, etc…) Saccharin sweetener was discovered this way Contact with the Eyes Eyes are particularly sensitive organs exposed directly to the environment Most labs have strict safety glasses or goggles policies Spills, splashes, and broken glass are common laboratory hazards You might feel safe to take them off because of what you are doing, but you can’t predict what your lab mates might do More on Eye Protection in Chapter 7 Inhalation: breathing hazardous chemical into your lungs Gases can get directly into the bloodstream due to gas exchange in lungs Volatile liquids = those that easily vaporize at room temperature

3. Keep chemical bottles closed when not using Work with volatile liquids and toxic chemicals in a chemical fume hood Homogeneous Mixtures: gaseous contaminants in (gaseous) air (same phase) • Vapor Pressure (volatility) is correlated to boiling point • Use the boiling point on the label to predict hazardous liquids

4. Heterogeneous Mixtures: solids or liquids in air (different phases) • Colloid or Aerosol = particles from 0.01 to 100 mm • Likely to occur when opening bottles, pouring liquids, spills • Concentrated acids “fumes” above the liquid—open only in a hood • Occur when grinding solids, handling fine powders, mixing solids Dangers of Aerosols • May stay in the air for hours, contaminating you later • Deposited in lungs, where they may react or dissolve and be absorbed • Larger particles may end up stuck in mucous and be ingested later Avoiding Exposure • If you can smell it, you are being contaminated • Some chemicals smell strongly, so smelling may prevent large exposure • Others have weak odor—the exposure may be serious before you smell • Treat all chemicals as potential hazards, don’t wait until it stinks!

5. Skin Exposure (dermal exposure) Most common route of chemical exposure Skin is actually good at protecting us from most chemicals Some chemicals react with the skin only; others are absorbed into blood Cuts or open wounds increase the danger of exposure—keep covered Spilled chemicals: small particles may expose the next user, be sure to clean up thoroughly, especially around balances Other safety precautions: wear gloves, lab coats, absorbent covering paper, closed toe shoes, Gloves • Don’t have to wear them all the time • Make sure you pick the right kind for the hazard • More on this topic in Chapter 7 Exposure by Injection Some advanced chemical techniques require syringes and needles Biological labs may have to make injections Broken glass can “inject” contaminants Use extreme care when using syringes and needles More on this topic in Chapter 4

6. Section 3.1.2 Signs, Symbols, and Labels Incident 3.1.2.1 Acetic Acid Explosion Tool, Toy, or HAZARD! Swimming pools, Fire, Airplanes, Cars, Medicines: Beneficial but Hazardous Chemicals are similarly useful but potentially dangerous Key: recognizing and respecting hazards before exposure or incidents Chemical Names—avoiding mistaken identity IUPAC Nomenclature: one specific name per chemical structure Common Names still (and probably always will be) used CAS (Chemical Abstracts Service) Number: a specific ID # for each compound CH3CH2OCH2CH3 = ether, ethyl ether, diethyl ether = CAS# 60-29-7 CAS # is listed on most chemical labels, often in square brackets: [60-29-7] www.chemindustry.com/apps/chemicalshttp://webbook.nist.gov/chemistry

7. Chemical Labels OSHA requires information about hazards of every chemical be on the label Law requires “Principle Hazard” Chemical may have other hazards not on the label Don’t let the Principle Hazard blind you to the other hazards! Terms describing various types of hazards should be familiar to you Symbols and Pictograms for various hazards are also used Department of Transportation (DOT) Placards for transported materials

10. Hazard Rating System Several rating systems for various hazards exist; NFPA (National Fire Protection Association) system is the most well-known: NFPA Diamond Lab conditions ≠ Fire Conditions—some chemicals aren’t as dangerous as labeled

11. Globally Harmonized System for Classification and Labeling of Chemicals (GHS) Incident 3.2.1.1 Isopropanol Explosion United Nations authorized GHS in 1992 to Standardize Chemical Labeling Similar to United States MSDS system, but with some differences Voluntary for nations to adopt and use Allows global marketplace where purchaser knows what they are getting

12. GHS “Purple Book” contains information on the various hazards

13. Each chemical is to be accompanied by an SDS (Safety Data Sheet) with 16 sections of hazard, handling, and disposal information. Much like USA’s MSDS System Federal Regulation “HazCom 2012” regulates full adoption of GHS in U.S. by 2016.

14. Section 3.1.3 Material Safety Data Sheets Incident 3.1.3.1 Chemical Sensitivity Infinite Number of Chemicals CAS had numbered over 81,000,000 compounds by 2013 Many have never been tested for toxicity: $100,000 per chemical using rats Tiny amount ever existed in one lab Chemical suppliers report what they know Rules don’t require full toxicity tests even if the chemical is bought/sold Good News: most of what you encounter will be known and toxicologically tested

15. 1980 OSHA “Hazard Communication Standard” required Material Safety Data Sheets Often called MSDS Sheets Required to be supplied to all purchasers/users of sold chemicals May be supplied as a paper copy (especially the first time you buy) Access to MSDS over Internet is now ubiquitous Most MSDS Sheets (although not required to) follow American National Standards Institute (ANSI) format GHS follows the exact same format for its “SDS” sheets Legally required, but may not be accurate Interesting to compare different suppliers Large chemical suppliers are generally reliable: Sigma-Aldrich; Thermo-Fisher; etc…

16. Using MSDS Sheets—general information Primarily, you will want to find information about hazards of the compound Also a good source for emergency responders as how to handle Information on how to dispose of chemicals is also valuable How to find Hazard Information on an MSDS Match the label of the bottle to the MSDS Sheet to make sure it’s the right one Hazard information is usually found near the beginning • “Hazard Identification” • “Physical and Chemical Characteristics” • “Fire and Explosion Hazard Data” • “Reactivity and Stability Data” • “Health Hazard Data” • Look for: “Corrosive”, “Flammable”, “Toxic”, “Irritant” Section on Personal Protective Equipment needed for use or clean-up • Not always specific: “Use appropriate protective gloves” • For clean-up: “follow state and local protocols” Critical Reading of MSDS Sheets First source of information, but may need more specific help Chemists often feels MSDS sheets overstate dangers: from NaCl MSDS sheet

17. Section 3.2.3 Interpreting MSDS Information Incident 3.2.3.1 Isopropyl Ether Detonation Gleaning Useful Information for Hazard Assessment from MSDS Sheets MSDS Sheets focus on industrial, large scale use of chemicals, not lab scale Types of information on the MSDS Data: simple information like mp, bp, aqueous solubility (should be correct) - One study showed >50% of 150 MSDS sheets had incorrect health information or exposure level information • 1997 report found only 11% of MSDS sheets were accurate on all four areas studied: health effects, first aid, PPE, exposure limits Recommendations about Safety Procedures, Medical Treatment, Disposal • Useful for large industry, not the chemical lab • May not be specific enough (gloves) • May not be updated as new information is learned

18. How MSDS Sheets are Written Scientist and/or Physician may write sections Lawyers will write others: there job is to avoid liability May have been written by a computer! Generic phrases correct but not useful Examples of MSDS Sheets (or their use) gone wrong Banning of Styrofoam cups because “Dihydrogen Oxide” used in manufacture Recommendation to flush eyes with water if exposed to “Saline Solution” Recommendation to wear safety glasses and lab coat for deionized water Don’t Dismiss Too Much Sucrose (table sugar) plant: makes sense to wear goggles and dust mask Sucrose dust (like wheat dust) can explode with right ignition source Ordinary chemicals can be hazardous under the right(wrong?) conditions Format of the Typical MSDS Sheet: Chemical and Hazard Identification (sect. 1-3) Section 1: Chemical Product and Company Identification Information: what it is and who made it Use: there for comparison to the product; contact info may be useful Section 2: Composition/Information on Ingredients Information: purity, CAS #, list of compounds in mixture Use: needed for an emergency or to clean up a spill correctly

19. Section 3: Hazards Identification Information: warning terms, potential health effects, exposure route Use: usually good on physical hazards, often lists so many health hazards without specifying extent of danger that it is confusing or useless New GHS Hazard Classification: assigns appropriate relative hazard ratings Emergency Measures (sect. 4-6) Section 4: First Aid Measures Information: general procedures if exposed, some give specific info for doctor Use: lets you develop a plan, important for doing the right first aid steps Section 5: Firefighting Measures Information: flammable properties, fire extinguisher, explosion hazards Use: lets you develop a plan, put out a fire, important for firefighters Section 6: Accidental Release Measures Information: what you should do for a spill Use: get correct spill kits, helps professional responders to a big spill Managing This Hazard (sect. 7-8) Section 7: Handling and Storage Information: industrial intent, general warnings (no flame), incompatibles Use: usually very generic and not very helpful for a lab

20. Section 8: Exposure Controls/Personal Protection Information: ways to prevent exposure (ventilation, gloves, safety shield) Use: more useful for employer, not specific enough for lab worker Hazard Recognition/Assessment Information (sect. 9-12) Section 9: Physical and Chemical Properties Information: just like it says Use: risk of vapor, flammability etc…; may help plan an experiment (mp) Section 10: Stability and Reactivity Information: conditions to avoid, incompatible chemicals, hazardous products Use: critical to someone doing reactions, helpful to emergency responders Section 11: Toxicological Information i. Information: known toxicity and human exposure limits, acute and chronic Use: lets user determine risks of using this particular chemical May not be fully tested, especially chronic (long term effects) Toxicity data changes with new data—check how old the MSDS is Section 12: Ecological Information Information: behavior in and effects on environment Use: informs how you will dispose of it, helpful if a spill occurs

21. Regulated Activities (sect. 13-15) Section 13: Disposal Considerations Information: US EPA Resource Conservation and Recovery Act (RCRA) requires all hazardous waste disposal be regulated; how to dispose properly Use: often very generic (follow all state and local regulations), but may mean more to waste specialist than to you. Don’t pour stuff down the sink! Section 14: Transport Information Information: US Dept. Transportation regulates shipping hazardous materials, tells about how to label and ship Use: mostly for someone shipping materials elsewhere, must follow rules Section 15: Regulatory Information Information: specific rules for regulated chemicals, reporting spills if too big Use: employer and EHS staff most concerned Other Information (sect. 16) Information: date of last revision, references, hazard ratings, disclaimers Use: hazard ratings are more specific, make sure using most recent MSDS

22. Section 3.2.2 Information Resources about Laboratory Hazards and Safety Incident 3.2.2.1 Dimethyl Sulfate and Sodium Azide Explosion 2. Internet Resources Google? Lots of misinformation (Google Scholar would be better) Wikipedia? Better, but still subject to errors (user produced encyclopedia) Recommendation: use reviewed material only when safety is at stake MSDS Sheets can easily be found on-line They have to exist, they don’t have to be correct Table 3.2.2.1 Lists many web sites with Reviewed Safety Information • Journal of Chemical Education • Sigma-Aldrich (on-line, or the printed catalog) • Chemical and Engineering News Printed Resources: a number of well-known books on laboratory hazards Research the reaction or technique BEFORE you do it (not after a problem occurs)

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24. Section 3.3.1 Chemical Hygiene Plans Incident 3.3.1.1 Hydrofluoric Acid Exposure Planning to Succeed Industrial Setting: large amounts of the same few chemicals for many years Laboratory Setting: Hundreds of compounds, used intermittently or only once OSHA: Employees are required by law to have a workplace free from hazards Students are not covered: moral and ethical reasons (not legal) to keep them safe 1990 OSH “Lab Standard” performance standard for Academic Labs They don’t tell you how to limit exposure They will test to see if you are and/or punish you if you aren’t (accident) Chemical Hygiene Plan (CHP) a. OSHA Requires; available to employees; How do we keep our staff/students safe b. Chemical Hygiene Officer (CHO): responsible for the developing and implementing the CHP (Tom Willis (recently retired), was SWOSU Dept. of Safety, Risk Management & Workers' Compensation)

25. Recommended CHO Duties Develop CHP and appropriate measures for handling chemicals Oversee the purchase, use, and disposal of chemicals Ensure adequate safety inspections and operations Assist in incident investigation Understand legal requirements