Warning: Graphite oxide explosions

Graphite oxide (GO; also known as graphene oxide) is an intermediate compound used in its own right and as a route to graphene. Several papers over the last few years have indicated that bulk GO, when heated, can explode; samples of a few milligrams created energy releases that damaged laboratory equipment. (Qiu, Y., et.al. Explosive thermal reduction of graphene-oxide based materials: Mechanism and safety implications. Carbon 72, 2014, pp215-223. Doi: https://doi.org/10.1016/j.carbon.2014.02.005)

Self-heating is also possible, particularly with addition of dopants such as hydroxyl ions (-OH), which drop the temperature for thermal runaway by as much as 50˚C. Such a reduction can overlap with common processing temperatures for GO.

Results presented at the recent American Chemical Society meeting in New Orleans (Green, M.J., et.al. Study of safer storage of graphene oxide. Paper number CHAS 3.) indicate that the temperature at which thermal runaway/explosion occurs drops as the amount of material increases due to mass and thermal transfer effects.

Storage of substantial quantities of GO therefore may pose both a laboratory and a process hazard. It is recommended that researchers working with this material minimize storage, perform a thorough literature search before heating GO, and take appropriate precautions to protect against mishaps.

Warning: Laser eye protection for ultrafast lasers may not be protective

Laser eye protection is normally rated using continuous-wave, narrow-bandwidth lasers. Nevertheless, some labs use pulsed lasers, which have wider bandwidths and higher peak powers; in the case of pico- and femtosecond pulses, this is taken to extremes.

Recent work at NIST and Hood College in Frederick, MD, has shown that much laser protective eyewear is not capable of withstanding fast laser pulses. (J. Laser Appl. 2017, DOI: 10.2351/1.5004090) 22 different pairs of eye protection were tested against a 40-80 fs pulsed laser, and more than half failed to perform as rated. All plastic protective lenses failed.

It is strongly recommended that when selecting laser protective eyewear, you test the eyewear against your particular use condition to ensure that they provide adequate protection. The Laser Safety Advocate, Niel Leon, is available to assist with testing of this sort.

Further information can be found in the cited paper and in this article in Chemical & Engineering News.

Hazard assessment resources from the ACS

Hazard assessment is an important part of the overall process of controlling hazards in the laboratory. The American Chemical Society recently developed a website that gives detailed information and tools for doing hazard assessments–tools that apply not only to chemistry but to all laboratory research.

I encourage all researchers to look at the ACS’s site to see what lessons can be learned. If you would like an introduction to the resources available or a “teach-in” on a particular part (e.g., standard operating procedures–what we call “experimental protocols” in academia), please contact me at dkuespert@jhu.edu.

Warning: Azidophenylalanine

The unnatural amino acid azidophenylalanine is used for modifying and labeling proteins in biological and biochemical research. The azido group, though, is often a bad actor, leading to “energetic events,” (i.e., explosions).

A recent article in J. Org. Chem. (doi:10.1021/acs.joc.8b00270) by Mark Richardson, Gregory Weiss, and other University of California researchers describes an inexpensive synthesis of this amino acid. In the course of the research, the researchers studied the intermediates and final product using differential scanning calorimetry and discovered that azidophenylalanine “behaved like an explosive compound,” an unexpected result. The authors recommend that crystalline samples of azidophenylalanine not be stored for long periods and that all stocks of the material be kept in dilute aqueous solution.

Further details can be found in a Safety Note in Chemical & Engineering News.

Keep an accurate chemical inventory


Having an up-to-date chemical inventory is important for efficient laboratory operations, but it is essential for emergency responders. By agreement with the Baltimore City Fire Department, each JHU laboratory containing chemicals must post an up-to-date chemical inventory on the entry door. It is the lab’s responsibility to maintain its inventory.

In practice, the inventory need include only the full English common name of the chemical (or the IUPAC name if there is no common name) and maximum quantities stored or used in the lab. The inventory must be updated before the annual Health, Safety, and Environment inspection in the Fall, but best practices would be to update quarterly or monthly, depending on the rate of chemical transfer in and out of the lab.

Please make an effort to ensure that your laboratories meet JHU’s commitment to the Fire Department. Accurate information on a lab’s contents allows the Fire Department to protect themselves more effectively and to minimize damage to a lab experiencing an emergency.

Learn the fundamentals of toxicology in your spare time

The National Library of Medicine makes available an online short course on toxicology available at https://toxtutor.nlm.nih.gov/index.html. ToxTutor even offers a certificate of completion if you sign up for the Library’s free learning management system.

Another good nonspecialist introduction to toxicology is The Dose Makes the Poison: A Plain-Language Guide to Toxicology (Frank, P., Ottoboni, M.A.; Wiley, 2011). This book provides an excellent introduction to toxic chemical hazards and is recommended for those who handle a variety of chemicals.

Lab safety posters

The safety posters below may be used by any JHU laboratory–just print them out and post!

Be sure to choose a poster suitable for your lab. A poster about lab coats is not appropriate in a mechanical lab where lab coats are forbidden (because they might catch on something). A poster about compressed gases might be a better choice in that case.

Rotate safety posters at least quarterly. Research shows that posters start to lose effectiveness quickly, so “switching them up” is a good way to keep your fellow researchers safety-aware.


How to test an eyewash or drench hose station

Most of our labs have eyewashes or drench hoses (pull-out eye/face/body washes) for emergency use. These must be tested periodically. Drench hoses (which are part of the sink) or eyewashes with plumbed drains (most do not) are the responsibility of the laboratory. Here’s how to test a drench hose or eyewash:

Run the spray for 3 minutes or until the water runs clear, whichever is longer. If the water does not run clear immediately, the sprayer does not immediately actuate, pressure is too high or low, or if the water is not a tepid temperature, contact Facilities Management at x6-8063 as soon as possible to have the sprayer repaired. After testing the eyewash, clean the sprayer and any covers with alcohol wipes.

Log the test date, result, and any corrective actions taken. Logbook sheets must be retained until 2 years have passed from the last test recorded on them. A PDF form to use for logbooks is contained in the university policy on emergency equipment at  https://hpo.johnshopkins.edu/hse/policies/156/10941/policy_10941.pdf?_=0.719595961086. Keep the logbook near the drench hose/eyewash station or place a small sign nearby stating the location of the log.

It is fine to use a single logbook for multiple drench hoses in a large lab, but use separate pages for each drench hose and label the hoses so you can tell which is which.

JHU lab safety “Who’s who”

Dan Kuespert, PhD, CSP

Homewood Laboratory Safety Advocate
Krieger School of Arts & Sciences/Whiting School of Engineering
410-516-5525 (x6-5525)
103G Shaffer Hall

Dan is a PhD chemical engineer who is a great point of contact for all things lab safety. He works jointly for the Deans of the School of Arts & Sciences and the School of Engineering. He acts as an internal safety consultant, providing training courses (both academic and informal), consulting (from answering simple questions to re-engineering experimental designs to help make them safer), and generally working to enhance the safety culture at Homewood.

Niel Leon

Homewood Laser Safety Advocate
410-516-6752 (x6-6752)
G-43 Wyman Park Building

Niel is the campus’ laser safety expert. He is the principal resource for laser-using faculty, staff, and students in developing safe practices, procedures, experiments, and facilities. A skilled mechanical engineer, Niel can frequently re-engineer a laser installation so that laser safety goggles are not necessary during normal operation.

Perry Cooper, MS, HEM, CCHO

HSE Manager
JHU Department of Health, Safety, and Environment
410-516-8798 (x6-8798)
G-2 Wyman Park Building

HSE is the University’s centralized occupational health and safety department. Although it is based primarily at the Johns Hopkins Medical Institutions in east Baltimore, Perry manages the office that services Homewood specifically. He is a certified hazardous materials manager and a certified chemical hygiene officer. Perry is your contact for policy issues, industrial hygiene advice, waste disposal, etc. HSE also provides the campus hazardous materials (HAZMAT) team, which handles chemical incidents too large for individual lab personnel.

Stephen Dahl, PhD, RBP

JH Biosafety Officer
410-955-5918 (x5-5918)
2024 E. Monument Street

Steve is Director of Biosafety for Johns Hopkins and a PhD microbiologist. He is your first point of contact for matters biological, ranging from consultations on sterilization methods to registration and risk assessment for proposed biological research. he also supervises the Health, Safety, and Environment annual laboratory inspection program.

Mina Razavi

Homewood Radiation Safety Officer
410-516-7278 (x6-7278)
Macaulay Hall basement

Mina is Radiation Safety Officer for the Homewood campus, and your contact for all things radioactive. She manages radiation licensing, materials ordering, personnel monitoring, regulatory compliance, and waste disposal. Always direct questions about JHU radiation safety policies and procedures to Mina.

Carolyn Schopman, RN

Occupational Health Nurse Manager
410-516-0450 (x6-0450)
Eastern C160 (New Location Aug 2017)

Carol oversees Homewood’s Occupational Health Services, which provides preventive medicine (e.g. vaccinations), medical surveillance (including respirator clearance), first aid and treatment for occupational injuries and illnesses, worker’s compensation services, and health training (e.g. CPR).


Transporting chemicals

There is often a need to move chemicals from room to room or between buildings. Hand-carrying hazardous chemicals can introduce a variety of ways that you, others, or the environment can be exposed. It is essential to transport chemicals properly in order to transport them safely. Tips for safe transport include:

  1. Carry bottles or jars in trays or bottle carriers instead of by hand—they are less likely to become broken, and the tray/carrier provides secondary containment.
  2. If using trays, push the tray on a laboratory cart instead of carrying it. Suppose you trip while executing the carry? A carried tray would fall and the contents would leak out.
  3. According to the National Academy of Sciences, carts used to transport chemicals should have at least a 2-inch lip to provide adequate containment.
  4. Do not crowd the bottle carrier or tray—trying to put two bottles in a single-bottle carrier or overloading the tray. This makes it more likely something will fall out.
  5. Line the bottom of the tray or carrier with vermiculite or a spill-absorbent pad to help absorb minor leaks.
  6. Bear in mind that some chemicals rapidly degrade or even explode in the presence of strong temperature changes or bright sunlight. Peroxide-forming chemicals are notorious for this if they have built up sufficient hazardous peroxides.
  7. Do not transport incompatible chemicals (e.g., acids and bases) together in the same tray or carrier.
  8. If moving chemicals further than the next lab, bring spill-management supplies along—the same spill kit you would use in your lab. Your quick action to clean up a spill can prevent a complex and expensive response by the JHU hazardous materials team or by the Baltimore Fire Department.
  9. When moving chemicals, it is a good time to verify that they have proper labeling: full chemical name, in English, is required (e.g., “isopropyl alcohol” instead of “IPA”). If there is not sufficient space to do this, use abbreviations and carry a key to the abbreviations with you to give to the new lab. Common chemical names are sufficient; full IUPAC nomenclature is not necessary.
  10. If the chemicals you are moving are heat-sensitive, package them in a box with a cold pack to maintain quality. If the chemicals may become shock-sensitive, consult with the Department of Health, Safety, and Environment before the move.