Maintaining the lab in a clean, organized state is important both for safety and for science. After all, you can’t be doing great science when you’re spending all your time looking for tools lost in piles of junk.
Here’s a checklist to help you organize your lab. Post it on the back of the door and teach every lab researcher to run down the checklist before leaving. Just a little bit of cleanup per day will eventually make the most messy lab a tidy, efficient, and safe place to do science.
Housekeeping score sheet 2022-10-11 DRK 1
In this month’s Safety Short, learn about how the military concept of Defense in Depth translates to laboratory safety.
There is a very successful concept in military strategy called Defense In Depth. It refers to the use of multiple layers of defensive measures; these are usually intended to cause damage to the enemy and then be abandoned. A similar concept applies in occupational health & safety.
In safety, Defense In Depth refers to the use of multiple layers of hazard controls to minimize risk.
Any risk minimization measure one might use to protect lab workers against a hazard will be less than 100% effective. Building sprinkler systems, for example, only work when water and electricity are available, and when the system is properly maintained.
We can add layers of protection to the sprinkler by establishing an inspection and test program for it, or by providing an alternative source of water. We can also add other risk minimization measures to add layers, such as building the laboratory out of noncombustible materials.
How effective each of these layers is can be determined from the NIOSH Hierarchy of Controls, which we discussed in June 2021. In general, engineering controls are more effective than administrative controls, which are in turn more effective than personal protective equipment. The laws of probability illustrate that the probability of an incident given 2 independent layers of protection will be less than or equal to the probability of an incident given only one layer of protection. Adding more independent layers reduces the likelihood of an incident.
If you have questions about layers of safety protection, contact Dr. Daniel Kuespert, Homewood Laboratory Safety Advocate, at [email protected]. See Dr. Kuespert’s website, https://labsafety.jhu.edu, for more safety information. As always, emergency response is available from Security at 410-516-7777.
Nanomaterials pose challenging health & safety issues, because the toxicity and other biological effects of many nanomaterials are unknown. It is entirely possible that nanomaterials can be much more dangerous than the base materials. For example, a lump of coal or a diamond is relatively nonhazardous, but carbon nanotubes have long been suspected of asbestos-like action on the lungs, leading to lung and pleural lining cancers. [https://blogs.cdc.gov/niosh-science-blog/2008/05/20/nano/]
The Centers for Disease Control and Prevention’s National Institute of Occupational Safety and Health recently issued four documents describing best practices for working with nanomaterials, including [items from CDC press release cited below]
• Handling and weighing of nanomaterials when scooping, pouring, and dumping;
• Harvesting nanomaterials and cleaning out reactors after materials are produced;
• Processing of nanomaterials after production;
• Working with nanomaterials of different forms, including dry powders or liquids.
The last item, working with nanomaterials, comes in a poster format suitable for hanging in the lab; the others are guidance documents.
It is strongly advised that researchers and principal investigators working with nanomaterials familiarize themselves with these documents, since they represent known best health & safety practice for their work.
The documents may be found on the CDC website at https://www.cdc.gov/niosh/updates/upd-03-12-18.html
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.
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.
Dan Kuespert, PhD, CSP
Homewood Laboratory Safety Advocate
Krieger School of Arts & Sciences/Whiting School of Engineering
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.
Homewood Laser Safety Advocate
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
JHU Department of Health, Safety, and Environment
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
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.
Homewood Radiation Safety Officer
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
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).
Inert gases such as nitrogen and argon are commonly used in our laboratories. If the contents of a cylinder were suddenly released into the laboratory atmosphere, the oxygen content of the air could be reduced below the safe 19.5% level necessary to avoid hypoxia in lab occupants.
Find out how to determine if a worst-case release of inert gas can reduce oxygen concentrations below safe levels and what you can do about the risk in this Safety Note: Inert Gas Safety.
The American Chemical Society has revised the commonly-used Safety in Academic Chemistry Laboratories for its eighth edition. All those who handle chemicals should be familiar with the information in this small booklet, although it is aimed particularly at first- and second-year chemistry students. Hardcopies can be ordered from the American Chemical Society (http://www.acs.org) or a free PDF can be downloaded from here.
Using high-pressure air or gases to blow off or dry parts can create embolisms—small bubbles in the bloodstream that cause blockages—if the nozzle comes in contact with your body. The law requires that you use special nozzles designed to prevent this risk. Alternatively, the gas pressure may be limited to allow gas to be used safely to clean and dry parts. The Laboratory Safety Advocate’s office has developed an inexpensive kit to help. Learn more in High Pressure Blow-Off Gas.
Click here to view a PDF write-up of the incident.
An academic department turned over two green laser presenters labeled “Class 2″ to the Homewood Laser Safety Advocate for evaluation because one seemed “too bright.” Normally, a Class 2 laser presentation pointer should put out no more than 1 milliwatt of energy.
Both presenters were found to be putting out more than 10 times the allowable amount of energy, including energy in the invisible infrared range, which is more dangerous. (Green laser pointers are actually infrared lasers that use special optics to generate green light from the IR.) The Laser Safety Advocate tested several additional pointers from that department, finding them all in conformance with their markings. The overpowered pointers were disposed.
The overpowered pointers were actually hazardous Class 3B lasers which should not be used in an uncontrolled lecture or presentation setting. Homewood limits the power of laser pointers to Class 2; testing has shown that brighter pointers are not necessary in any lecture hall on campus. The class of a laser device is stamped on a small yellow or white sticker on the product.
These were name-brand laser pointers purchased from nonstandard sources (e.g., online auction sites); we are as yet unsure whether they were genuine branded products that are off-specification or if they were counterfeit. Please buy all laser pointers from standard JHU-approved sources such as Office Depot; unusual distribution channels are more likely to sell counterfeit or otherwise out-of-specification products. A sample of the sample laser presenter purchased from a JHU-preferred vendor measured within normal safe tolerances.
In 2013, the National Institute of Standards and Technology (NIST) found that 90% of green laser pointers and 44% of red laser pointers were out of compliance with federal safety regulations and their markings.
If you have a laser pointer that seems too bright, especially if it is green, contact the Homewood Laser Safety Advocate, Niel Leon, [email protected]. He can test your laser pointer and return it to you if it is safe to use (or help you find a source for a safe one if it’s not).
See the HSE Guidance Document on laser pointers, as well as this fact sheet(Laser pointer fact sheet v9-170725FNL), for more details.