Tag: safety aids

Worksheets and other materials to help labs work more safely

Managing experimental scope changes

All experimental protocols have a scope—that is, every experiment has parameters such as pressure, temperature, power, force, chemical identity, etc.

Many people think that performing safety analysis on an experiment is “too much trouble” because they don’t want to have to do it each and every time they change a parameter. This is not true; such people misunderstand how to use safe experimental design methods.

When we plan an experiment, the range of parameters we expect—pressure ranging from 0 to 50 bar, for example, defines a set of safe operating conditions– what I like to call a sandbox. Provided you do an appropriate safety analysis for the range of safe operating conditions you expect to use in your experiment, you can do experiments anywhere within the sandbox you like. Want to move your 5 bar experiment to 15 bar? If your safe operating pressure is defined as 0—50 bar, no additional safety analysis is necessary.

It is only when we leave the sandbox—vary parameters outside the range we’ve already studied—that additional safety analysis is needed. Recognizing when you have a need to vary outside your known safe parameters and doing the appropriate safety analysis—expanding your sandbox—to verify that the variation is safe is called Management of Change.

So an efficient and safe experimental design takes into account the widest anticipated variation in parameters—it makes the sandbox as big as possible. This requires a little thought at the beginning of an experimental series: exactly how hot might you need to operate? Exactly which chemical solvents might you need to use? It takes far less time to do safety checks on a broad scope of experimentation than to do smaller ones piecemeal during lab work—and it is far more likely to be done properly because you won’t be in a hurry to get back to the bench.

If you would like assistance in safe, efficient, broad-scope experimental design, contact the Laboratory Safety Advocate, Dr. Daniel Kuespert, CSP, at dkuespert@jhu.edu.

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).


Embolisms from high-pressure gas

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.

Unattended experiments

Some experiments take time: hours, days, even weeks. This means that the experiment will be set up and running in the lab while you are not there. You have an ethical obligation to prevent harm to others in the lab by ensuring that they are aware of your experiment and its hazards. Make sure they know:

  • What the purpose of the experiment is;
  • To whom it belongs;
  • What behavior indicates that something has gone wrong; and
  • What to do if something does go wrong.

You could tell the members of the lab all that information, but some lab members might not be present and others will promptly forget. Depending on the lab’s occupants to “know what’s going on” is foolish—your colleagues may know the general type of research you do but they are not familiar with the details of all your experiments. Far better is to post the information so that anyone in the lab can easily see what your experiment is, how to identify abnormal situations, and what to do in that event.

A sample form is available for you to use directly or adapt to your lab’s needs. (The file is in Word format for easy modification.) The form is written to allow use in teaching as well as research labs. You should prepare two copies of the form: one to post near the experimental apparatus and one to post in a safe place (like on the door). In an emergency, no one may be willing to approach the apparatus to read the information sheet!

Protect your eyes from high-intensity light

Protect your vision when working with UV germicidal lamps; lasers; welding and arc lamps; or other highenergy light sources. Special goggles limit the amount of light that can reach your eyes and skinThe type and amount of protection depends on the frequency, nature, and intensity of light. Learn more in Light eye protection.

Protect your face with a face shield

When a hazard involves a lot of energy or aggressive chemicals, your face may be at risk as well as your eyes. Also, Z87.1 or Z81+ rated eye protection may not be adequate to protect your eyes, so additional protection might be prudent. If you could injure your face in an accident, use a face shield to protect your face – learn more in High energy facial protection.

Protect your eyes from physical hazards

Physical hazards require eye protection designed for physical hazards. Always wear safety glasses or goggles when working with manual or power tools that may produce small particles (e.g.sanding, milling, cutting, hammering, scraping, etc.); working with tools that can generate droplets or a strong (>20psi) fluidstream, whether the fluid is air, water, or something else; processes producing lots of dust or other particles in the air (e.g., blowing leaves or snow from the sidewalk). Learn more in Physical hazard eye protection.

Protect your eyes from chemical hazards

Chemical hazards require eye protection specifically designed for chemical hazards. Many chemicals can cause serious damage or irritation when they get into your eyes. These include, but are not limited to, acids, caustics and solvents. When working with chemical eye hazards, wear chemical splash goggles to protect your eyes – learn more in Chemical Hazard Eye Protection.

Is your plastic gas tubing an over-inflated balloon?

Many labs use compressed gases, and often we use pressure regulators to step down the 2000-3000 psi in the cylinder to the use pressure. If the regulator can produce more than about 30 psi outlet, your plastic tubing might be in danger of rupture. Read more about how to fix this without buying a new $500 regulator in How to prevent plastic tubing rupture.