Office of Environmental Health & Safety A. Introduction 2-Methylbutane, commonly called isopentane, has a number of physical, chemical, and toxicological properties that make it especially hazardous to handle. Isopentane is a colorless liquid with a strong gasoline-like odor. It is a highly volatile, highly flammable, acutely toxic chemical. Prevention of exposure and elimination of potential ignition sources must be the primary goal when working with isopentane. *Disclaimer* - This document is a summary of general and manufacturer guidelines for the safe use, storing, and handling of isopentane. Researchers who plan on using isopentane must perform a hazard analysis of the experimental procedure, storage, laboratory design, potential risk, and disposal in order to determine if more stringent protective measures should be taken prior to purchasing or working with the chemical. Standard operating procedures (SOP) must be developed detailing exactly how the chemical will be stored, how the procedure involving the chemical will be performed, how potential ignition sources will be controlled, how workers in the area will be informed of the potential hazards, personal protective equipment requirements, spill procedures, fire contingencies, waste handling, and emergency procedures. The SOP must be submitted to OEHS for review prior to the chemical s use. Contact the OEHS (OEHS@tulane.edu) with specific questions, if needed. B. Physical Properties Compound: 2-Methylbutane Synonyms: Isopentane; ethyldimethylmethane; isoamyl hydride; 1,1,2-trimethylethane CAS No: 78-78-4 Mol. Formula: C 5 H 12 Mol. Weight: 72.15 g.mol -1 Flash point: -51 C (-60 F) closed cup Boiling point: 28 C (82 F) Vapor pressure: 76.992 kpa (20 C) Description: Colorless liquid, colorless vapor, strong gasoline-like odor, odor threshold at 400ppm Solubility: Flammability: C. Chemical Properties Insoluble in water Highly flammable, highly volatile Isopentane is a colorless liquid with a gasoline-like odor. It is commonly used as a blowing agent and for the freezing of biological samples with dry ice or liquid nitrogen. It is an extremely flammable liquid and vapor with a boiling point just above ambient temperature and a very low flash point. It can form explosive mixtures with air and oxidizing agents. Due to extreme flammability and ease at which it changes from liquid to vapor phase at or near room temperature, it must be handled, stored, and 1440 Tulane Avenue, New Orleans, LA 70112 P 504.988.5486 F 504.988.1693 W tulane.edu/oehs/
used with extreme caution to prevent ignition. Only explosion proof and non-sparking tools should be used when handling. Isopentane vapor is heavier than air and may travel to a distant ignition source. While considered nonreactive, isopentane can react violently with oxidizing agents, such as perchlorates, peroxides, permanganates, chlorates, nitrates, chlorine, bromine, and fluorine. D. Toxicity 1) Skin Contact Isopentane can affect exposure areas of the skin through direct contact. Common symptoms include irritation and burning of the affected area with possible swelling. Prolonged or repeated exposure can cause drying or cracking of the skin. 2) Eye Contact Isopentane contact with the eye can cause irritation and burning of the eyes, including swelling of the conjunctiva. 3) Inhalation Inhalation of isopentane vapors may cause peripheral neuropathy. Immediate symptoms include irritation to the nose, throat, and lungs, coughing, wheezing, and shortness of breath. Prolonged exposure symptoms include dizziness, drowsiness, headache, loss of appetite, confusion, and unconsciousness. Exposure may be fatal if swallowed and if it enters the airways as an aspiration hazard. The Threshold Limit Value (TLV) set by the ACGIH is 600 ppm as a time weighted average exposure for 8 hours. The Permissible Exposure Limit (PEL) set by the U.S. Occupational Safety and Health Administration (OSHA) is a time weighted average exposure for 8 hours of 1,000 ppm. The National Institute for Occupational Safety and Health (NIOSH) has set the recommended airborne exposure limit (REL) to 120 ppm averaged over a 10-hour workshift and 610 ppm, not to be exceeded during any 15- minute work period. 4) Ingestion It may irritate the mouth and throat, and is potentially fatal if swallowed and allowed to enter the airways as an aspiration hazard causing pneumonitis. 5) Chronic Toxicity Isopentane is considered a Category 3 under GHS classification for specific target organ toxicity-single exposure (heart and lungs), and of the central nervous system. 6) Environmental Toxicity Classified as a Category 2 under GHS classification for acute aquatic toxicity. E. Working with Isopentane 1) Preparation Before conducting any research with isopentane, the PI must: Create a comprehensive SOP for isopentane use in snap freezing to include, but not limited to the information contained within this document, the SDS, and appropriate first aid procedures and spill kits. Train all research staff on the SOP and document that training was provided and understood. Ensure research staff read an SDS for isopentane. Ensure research staff read this document and consult the references below. 2 P age
Ensure research staff are trained in all procedures for emergency response to include, but not limited to injury, exposure, spills and releases. Document that training was provided and understood. Ensure research staff are trained in the dangers of inhalation, ingestion, and skin contact, especially with concentrated solutions, and know the symptoms of exposure as well as emergency response for exposure. Document that training was provided and understood. Document all other training provided to research staff and verify that it was understood Obtain a chemical spill kit and review the procedures to follow in the event of a spill. Ensure all possible ignition sources around the working area are removed, including: - Power down electronic equipment that is not rated as explosion proof or flammable-safe, - Keep ovens elevated off of the floor, - Extinguish Bunsen burners immediately, - Be aware of the location of hot surfaces (e.g. hot plates, heat guns, ovens), - Beware of vapors accumulating in low areas to form explosive concentrations. Contact the OEHS (OEHS@tulane.edu) with specific questions, if needed. 2) Designated Working Area Isopentane should always be handled at least 6 inside of a fume hood. The SOP should be posted or readily available near the designated area. A chemical spill kit should be nearby. Ensure you have ready access to a good supply of running water and know the location of the safety shower and eyewash. Use non-sparking tools and equipment. Ensure all possible ignition sources around the working area are removed, including: - Power down electronic equipment that is not rated as explosion proof or flammable-safe, - Keep ovens elevated off of the floor, - Extinguish Bunsen burners immediately, - Be aware of the location of hot surfaces (e.g. hot plates, heat guns, ovens), - Beware of vapors accumulating in low areas to form explosive concentrations. Keep workstation as close as possible to storage location to minimize spilling risk. 3) Personal Protective Equipment (PPE) Recommended PPE includes: Fire retardant laboratory coat and antistatic pants. Close-toed shoes. Electrostatic discharge gear - Wrist straps, sole grounders Full-face shield in conjunction with goggles. Nitrile gloves should be used for general use. If extended exposure, use Viton/butyl gloves. 4) Safe Laboratory Practices Never work with isopentane alone or after hours. When purchasing isopentane, try to obtain the smallest volume possible for the work to be completed. Do not purchase large quantities unless absolutely necessary. Ensure all containers of isopentane are clearly labeled. Label containers before handling isopentane. Use only non-sparking tools. Do not use compressed air for filling, discharging, or handling. Minimize the quantity poured from the stock container. 3 P age
Perform a dry run of the snap freezing process without isopentane to identify any flaws in the SOP that need to be readdressed. Ensure isopentane-containing vials and flasks are securely supported and not likely to tip over. Do not eat, drink, or smoke while in the lab. 5) Storage of Isopentane Isopentane is an extremely volatile and flammable substance. Keep in a tightly closed container. Containers of isopentane must be stored separately from oxidizing agents, such as perchlorates, peroxides, permanganates, chlorates, nitrates, chlorine, bromine, and fluorine. Ground isopentane container and transfer container. Ensure storage container is properly labeled with full chemical name and associated hazards in accordance with GHS and HAZCOM regulations. Store away from electric sources, sparks, flames, and heat and other known ignition sources Isopentane storage guidelines vary depending on the vendor; check the safety data sheet for vendor recommendations. Storage recommendations include a flammable-rated cabinet engineered to contain flammable fuels, solvents, and chemicals at room temperature. Isopentane can also be stored in a laboratory-safe (also called flammable-safe) refrigerator, engineered for the storage of volatile or flammable chemicals with no internal electrical components, at 2-8 C. Store locked up. 6) Transporting Isopentane If an isopentane-containing solution must be transported from one lab area to another: Place the object directly from the laboratory-safe refrigerator or flammables cabinet into an insulated cooler. Remove your gloves before transporting the container to avoid the possibility of chemical contamination on your gloves spreading to door handles and other objects. Consider wearing a single clean glove with which to carry the container, leaving an ungloved hand to open doors and handle other objects, or have a lab mate open doors and handle objects for you. Once destination is reached, immediately move isopentane solution into approved storage area. Smith, Marne A 2/1/17 2:11 PM Comment [1]: Locked up how? And why? Cieslinski, Gerald B 2/1/17 3:16 PM Comment [2]: The store locked up is a GHS precautionary statement P405. No specifics given, just a statement. Smith, Marne A 2/1/17 2:11 PM Comment [3]: I think Kellie said that do not use refrigerators for isopentane. 7) Managing Isopentane Containing Waste Waste isopentane should be placed in a chemically compatible container that is clearly labeled as Hazardous Waste and that is compliant with all Tulane waste container policies (e.g. secondary containment, closed cap, etc.). Dispose of isopentane-containing hazardous waste containers following the usual hazardous waste disposal procedures. Empty isopentane containers must be double rinsed with water before disposal, with the rinsate disposed as isopentane waste. The bottles can then be defaced and disposed in standard waste containers. Contact OEHS at OEHS@Tulane.edu for hazardous waste pickups and disposal through a qualified vendor. Ensure all possible ignition sources around the working area are removed, including: - Power down electronic equipment that is not rated as explosion proof or flammable-safe, - Keep ovens elevated off of the floor, - Extinguish Bunsen burners immediately, - Be aware of the location of hot surfaces (e.g. hot plates, heat guns, ovens), Beware of vapors accumulating in low areas to form explosive concentrations 4 P age
F. First Aid If exposed to isopentane, move out of the dangerous area and contact TUPD. Show SDS to the emergency medical personnel in attendance. Fill out a First Report of Occupational Injury/Illness form. 1) Skin exposure: Immediately wash skin with soap and plenty of water. Use safety shower if large area of body is exposed. Remove contaminated clothing. 2) Eye exposure: Immediately flush eyes with cool flowing water, preferably at an eyewash station, or use sterile eyewash solution. Hold the eyelids open and away from the eye during irrigation to allow thorough flushing of the eyes for at least 20 minutes or until emergency medical help arrives. 3) Inhalation of Vapors Immediately move affected person to fresh air. Keep victim at rest and in position comfortable for breathing. Consult physician. If breathing has stopped, contact TUPD for medical assistance. 4) Ingestion: Do not induce vomiting. Never give anything by mouth to an unconscious person. Contact TUPD for medical assistance. G. Isopentane Spills 1) Be familiar with isopentane and associated hazards. Consult an SDS and the chemical literature to discover: boiling points, flash points, and vapor pressures at room temperature characteristic reactivities toxicities routes of exposure and target organs first aid procedures for exposures disposal procedures 2) Minimize the number of potential ignition sources should there be a spill: Power down electronic equipment that is not rated as explosion proof. Keep ovens elevated off of the floor. Extinguish Bunsen burners immediately. Be aware of the location of hot surfaces (e.g. hot plates, heat guns, ovens). Beware of vapors accumulating in low areas to form explosive concentrations. 3) Evacuate personnel to a safe area and follow the protocols listed in this document for major or minor spill (as applicable). 4) Ensure adequate ventilation. Utilize all local ventilation that is available. 5) Know the location of safety equipment: fire extinguisher 5 P age
eye wash station safety shower spill kits 6) Spill kit essentials: Instructions on how to clean up an isopentane flammable liquid spill. Sand or inert absorbent. Personal protective equipment (PPE) - Eye protection - Nitrile gloves - Shoe covers 7) Major Spill Protocol - A spill that is characterized by any of the following descriptions should be considered a major spill: (a) Someone has been injured, (b) A fire or explosion has occurred or is likely to occur, (c) The type or quantity of chemical released poses an immediate risk to health, (d) There is an impact on public spaces or spaces adjacent to the area where the spill occurred, (e) You and/or your lab-mates are unable to address the spill without assistance. Response: - Alert nearby coworkers and evacuate to a safe distance. Alert the Principle Investigator (PI)/Supervisor. - Remove ignition sources (e.g. no open flames, turn off hot plates and heat guns). - If a fire, explosion, or toxicity hazard exists, pull the fire alarm and follow building evacuation procedures. A person familiar with the situation should greet Tulane Police when they arrive and provide the relevant safety data sheets (SDS). - If you have not pulled the fire alarm, exit the area, close doors of affected areas and prevent re-entry. Put up Do Not Enter signs. Do not attempt to clean-up the spill. - Do not re-enter the area until instructed to do so by emergency response personnel. - If the accident involves personal injury or chemical contamination: a) Move the injured person to safety if it is safe to do so and provide first aid as noted above. b) As soon as practically possible, file a First Report of Injury. 8) Minor Spill Protocol - a spill may be considered minor if the spill to present relatively low hazards and no one has been injured or chemically contaminated. Response - Alert nearby coworkers of the spill and request their help (if they are qualified). Alert the PI/Supervisor. Contact the OEHS office at (504)-988-5486 for additional assistance, if needed. - Isolate the area. Close lab doors and evacuate the immediate area if necessary. - Ensure all possible ignition sources around the working area are removed, including: a) Power down electronic equipment that is not rated as explosion proof or flammable-safe, b) Keep ovens elevated off of the floor, c) Extinguish Bunsen burners immediately, d) Be aware of the location of hot surfaces (e.g. hot plates, heat guns, ovens), - Beware of vapors accumulating in low areas to form explosive concentrations - If the spill is not in a laboratory with strong ventilation (e.g. fume hoods present and working), establish exhaust ventilation to the outside. - Consult SDS for hazard information and cleanup instructions. - Locate the spill kit, which should be present in the lab. - Only use non-sparking tools. - Don appropriate personal protective equipment. At a minimum this should consist of safety glasses, nitrile gloves, and a fire retardant lab coat. - Control the source and confine the spill using spill kit supplies. Do not let isopentane enter drains. 6 P age
- Do not wash away material into a sink or sewer. Block drains and sewers if possible. - Once spill is contained, absorb with sand or inert absorbent, collect with an electrically protected vacuum cleaner, or clean area with wet-brushing. Ensure all equipment and tools are non-sparking. - Place debris in an appropriate compatible container, close the container, attach a Hazardous Waste sticker and notify OEHS at OEHS@tulane.edu to ask for a waste pickup. - Explosive atmospheres may linger after disposal. Allow area to ventilate, especially confined areas, and check atmosphere with PID or portable VOC meter, if possible. H. References 1) Isopentane Safety Data Sheet. Sigma-Aldrich, February 2015. http://www.sigmaaldrich.com/msds/msds/displaymsdspage.do?country=us&language=en&produ ctnumber=277258&brand=sial&pagetogotourl=http%3a%2f%2fwww.sigmaaldrich.com%2fcat alog%2fsearch%3fterm%3disopentane%26interface%3dall%26n%3d0%26mode%3dmatch%252 0partialmax%26lang%3Den%26region%3DUS%26focus%3Dproduct (checked January 2017). 2) Isopentane. The National Institute for Occupational Safety and Health. April 1994. https://www.cdc.gov/niosh/ipcsneng/neng1153.html (Checked January, 2017) 3) Isopentane New Jersey Right to Know Hazardous Substance Fact Sheet. NJ.gov. 2009. http://nj.gov/health/eoh/rtkweb/documents/fs/1064.pdf (Checked January, 2017). 4) Isopentane Praxair Material Safety Data Sheet. Praxair.ca. 2016. http://www.praxair.ca/- /media/documents-en/safety-data-sheets-en/isopentane-msds-e4612.pdf (checked January 2017). 5) Isopentane. INCHEM.org. 2014. http://www.inchem.org/documents/icsc/icsc/eics1153.htm (checked January 2017). 6) Prudent Practices in the Laboratory: Handling and Management of Chemical Hazards. National Research Council. 2011. 7 P age