Last Revised: April 21, 2022

Last updated: 4/2022

Quick answers to your most frequently asked questions.   

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Laboratory Waste

Laboratory Waste

1. I have a large number of expired or unneeded chemicals; must I submit an individual waste request for each container?

No. Submit one Waste Request Form and indicate approximately how many containers need to be picked-up.  Someone from EHRS will contact you soon to provide additional guidance and to coordinate the pickup

2. I have some unwanted or empty compressed gas cylinders; who do I contact to have them removed?

Whenever possible, gas cylinders should be returned to the manufacturer or supplier that owns them.  Contact information can generally be found printed on the cylinder label or hang tag.

For lecture bottles, disposable propane/MAPP gas or other cylinders that cannot be returned, submit an online Waste Request Form to schedule a pickup with EHRS.

3. How do I dispose of a glass-disposal box?

When glass-disposal boxes are 2/3 full, boxes must be closed, sealed, and placed next to the landfill waste for removal by the housekeeping staff.  Please ensure boxes are lined with a heavy plastic clear liner and the cardboard is not compromised.  Refer to the EHRS Laboratory Glassware/Plasticware Disposal Policy for more information.

4. What is a p-listed chemical?

Certain acutely hazardous chemicals, known as “p-listed” chemicals, have special disposal requirements with regards to unwanted reagents, empty containers, and broken bottles/spill cleanup.  Common p-listed chemicals that you may have in your lab include sodium azide, sodium cyanide, potassium cyanide, and copper cyanide.  Click here to access a complete list of p-listed chemicals.  

For guidance on the management of p-listed hazardous waste, see the P-Listed Hazardous Waste Fact Sheet on our website or contact for more information.   

5. How can I get a partially filled chemical waste container removed from my lab?

If you have partially filled carboys or other partial containers that you want to get picked up, please place a prominent check mark on the top right side of the chemical waste label.  This signals to EHRS that the container is ready to go even though it is only partially filled.  Click here for more information or to submit a request.

6. Do I need secondary containment for the waste bottles in my fume hood?

Yes!  Fume hoods are not considered secondary containment for any bottles identified as liquid waste (e.g., those with yellow chemical waste labels).  Secondary containment bins for liquid waste can be requested through EHRS using the Chemical Waste Pickup FormPlease note, secondary containment rules do not apply to intermediate containers stored in the hood.  For more information, see Penn's Chemical Waste Management Guidelines

7. Do I need to separate my halogenated and non-halogenated organic solvent waste streams?

EHRS strongly encourages you to separate halogenated organic solvent waste from non-halogenated organic solvent waste if your lab space isn’t restricted or made unsafe due to the physical footprint from these two waste carboys.  The main reason for the separation is disposal cost.  Halogenated solvents are about 9 times more expensive to dispose of than non-halogenated.  For example, the disposal cost for a 5-gallon carboy of non-halogenated waste is $4.00 versus $37.50 for a 5-gallon carboy of a halogenated mixture at greater than 50% halogenated.  For more information, see Penn's Chemical Waste Management Guidelines

8. How long can I store chemical waste in the lab?

Routine waste streams such as solvent and dilute aqueous waste, pump oil, and silica can remain in the lab no longer than 12 months.  Higher-hazard waste such as reactives, strong corrosives, and highly toxic chemicals can remain in the lab for no longer than 3 months.  For more information, see Laboratory Waste Chemical Management Guidelines.  

9. How do I dispose of my empty chemical bottles?

Unless a container held a chemical that is defined as acutely toxic, or P-listed according to the EPA, an empty bottle that has, through reasonable means, been emptied of its contents may be triple-rinsed, defaced of its labels, and disposed of as regular trash or with recyclables.  At Penn, each building/school may vary slightly in how these empty and defaced bottles are collected and disposed.  We encourage you to reach out to your building administrator with any questions about this.  See Disposal Guidance for Empty Chemical Containers for more information. 

Laboratory Safety

Laboratory Safety

1. I think my fume hood is malfunctioning.  What should I do?

Close the hood sash and do not use the hood until EHRS confirms it is functioning properlyContact your building administrator to open a work order.  If the hood is not put back into service within 5 days of contacting your building administrator, contact EHRS. For more information, see our Fume Hood website.

2. How I do a report a safety concern or observation in my lab?

There are several avenues you can pursue for reporting a safety concern in your lab. You may fill out this webform on EHRS’s website. If you want to report the concern anonymously, you may do so using Penn’s Confidential Reporting and Help Line, P-COMPLY.  BioRAFT users can also report lab and lab-building related safety issues, anonymously or non-anonymously, directly through BioRAFT by using ObservNow (Pennkey login required).

3. Do I need to flush my emergency eyewash?

Yes!  Eyewashes need to be activated weekly to ensure proper function and clean water.  Test the eyewash in your laboratory if it drains into the sink or is plumbed to a drain.  Continue to test it on a weekly basis.  Contact your building administrator if your eyewash is not functioning properly or if it drains to the floor.  Click here for a video clip from a Penn lab that shows why flushing your eyewashes is so important. 

4. How do I request more chemical inventory barcode labels for my lab?

To request more barcode labels for your chemical inventory, please complete our webform to officially route your request to our Chemical Inventory Team.  The barcode request section is at the bottom of the form.  A member of our Chemical Inventory Team will deliver the labels to your lab.

5. Does the EHRS lab inspection checklist ever change?

Yes!  We frequently update our checklist as regulations and policies change and as we learn new information that will improve lab safety.  EHRS recently created a new finding in BioRAFT for fume hoods that are found in “purge” (emergency exhaust) mode during lab inspections; for more information, see our Fume Hood website.  We also updated our “chemical waste stored in the laboratory too long” finding to include language about disposal of partially filled containers; see the “Laboratory Waste” section of our Lab Safety Quick FAQ archive for more information.  Lastly, we added a new finding “floors/aisles are obstructed within less than 36 inches” for use in situations where a walkway is obstructed, hindering emergency egress.

 6. What type of gloves should I use when working with chemicals?

Disposable nitrile gloves (minimum thickness of 4 mil) provide adequate protection against accidental hand contact with small quantities of most laboratory chemicals.  For exceptions, review Fact Sheet: Disposable Nitrile Gloves in Chemical LabsLab workers who contaminate their gloves should immediately remove them, wash their hands, and don new gloves.  Lab workers should contact EHRS for advice on chemical resistant glove selection when direct or prolonged contact with hazardous chemicals is anticipated.  More details about the proper use and limitations of nitrile glove use can be found at Lab Coat, Gloves and Safety Eyewear Policy

7. Why are we still getting reminders to certify our Chemical Hygiene Work Plan form?  I thought we already did this!

Your lab’s Hazards List and Chemical Hygiene Work Plan are two separate documents that must be certified by your PI.  To complete certification of both, your PI must: 1) click on the Hazards List link in the notification email and sign in with their PennKey; 2) then click "submit" at the bottom of the page to certify the Hazards List; and 3) scroll to the bottom of the following page for the Chemical Hygiene Work Plan and click "submit" there as well to finish the certification.  If the PI misses the second submission, they’ll continue to get reminders.  For more information, see How to Certify the Lab Hazard Identification Survey in BioRAFT

8. How do I contact EHRS with my questions? 

EHRS is now offering weekly Drop-In Hours!  Lab Safety Specialists and Biosafety Officers will be available on Wednesdays from 12-2 to answer your questions live at  However, you can contact EHRS any time through via email at or via phone at 215-898-4453.  Should you wish to connect with a specific individual, you can find their contact information on our website hereBioRAFT users can also report lab and lab-building related safety issues, anonymously or non-anonymously, directly through BioRAFT by using ObservNow (Pennkey login required).

9. How should I notify EHRS that my lab is closing or relocating?

EHRS has a webform that must be submitted when a lab is preparing to close.  It may be submitted by anyone with information about an upcoming lab move or closure.  It should be submitted as soon as possible so that we can help lab occupants to responsibly shutdown operations and prepare to vacate.  Refer to these Lab Close-Out Procedures for tasks that are required before the lab is vacated. 

10. How do I safely remove a stubborn gas-cylinder valve cover?

The use of excessive force and inappropriate tools for removing stubborn gas-cylinder valve covers poses a serious potential hazard.  The SOP for Compressed Gases on the EHRS website offers guidance for handling this situation in the “Storage and Transport” section.  An appropriate cap-removal tool, available through AirGas, may be required and is the lab’s responsibility to purchase.  For specific information on these options and guidance on handling tight cylinder caps, see our SOP: Compressed Gases

Chemical Storage

Chemical Storage, Transport, and Labeling

1. Can all acids be stored together in the same cabinet?

Strongly oxidizing acids (e.g. Perchloric acid, nitric acid) are incompatible with organic materials, including organic acids (e.g. Glacial acetic acid).  These compounds react vigorously.  Mineral acids (ie. HCl, H2SO4) can be stored with either acid type.  If a separate cabinet is not available, use secondary containment to segregate incompatible acids.

2. Should I wear my lab coat and gloves when transporting chemical or biological samples outside my lab?

No.  PPE (including lab coat and gloves) must not be worn in public (non-lab) spaces or outside of the building.  Instead of wearing PPE, package your materials so that everything is appropriately contained.  Use secondary containment to protect not only yourself, but also the rest of the University and the community at large.

3. How do I get rid of empty gas cylinders?

Contact the Airgas Penn support group at 855-636-6316 to enter a ticket for the request of additional empty gas cylinders pick-ups.  Airgas is able to take most gas cylinders, but if you are unsure if your cylinder is eligible for Airgas pick-up, just ask when you call.


1. Who do I contact to have my Biosafety Cabinet serviced?

Technical Safety Services (TSS) is a new BSC vendor available on campus that provides certification and repair services.   See the BSC Certification & Repair section of the Biosafety Cabinet page on the EHRS website for more information about how to contact TSS and how to prepare your cabinet for service.

2. What’s the difference between a Biosafety Cabinet, a Clean Bench and a Chemical Fume Hood?

Biosafety Cabinets (BSCs) are used when working with infectious agents and human source material to protect the product, personnel, and environment. Clean benches provide protection for the product only. Fume hood are used for handling chemicals and protect personnel only. More information on Biosafety Cabinets can be found on our website at Biosafety Cabinets.  More information on Fume Hoods can be found our website at Fume Hood Specifications.

comparison of three equipment types

3. How do I safely conduct flame sterilization on an open bench using ethanol?

We do not recommend using ethanol and flame sterilization and encourage alternative approaches. However, if you must, EHRS recommends following the guidance for suggested PPE, work area preparation, ethanol preparation, etc. outlined on our recently created Fact Sheet: Flame Sterilization on the Open Bench

4. How do I properly dispose of a disposable sharps container?

The lid for disposable sharps waste container must be closed and lid securely fastened when the container is 2/3 full.  To properly dispose, first autoclave the closed container if is contains biological contaminants, then place it in the biohazardous collection bin (*do not autoclave chemically contaminated sharps).  If you do not have access to an autoclave, set up an account with Curtis Bay Energy to use their Reusable Sharps Containers.  For more information, refer to Proper Disposal of Sharp Objects and Laboratory Waste Disposal Guide.

5. My lab participates in the Reusable Sharps Container Program and one of our reusable sharps containers has not been emptied. What should I do?

Removal of reusable sharps containers for infectious waste is fulfilled by an external vendor, Curtis Bay Energy, who is also responsible in making sure that the containers are checked and replaced on a weekly basis.  If your reusable sharps waste container has not been checked or replaced routinely, notify the customer service representative for Curtis Bay Energy.  Information about the reusable sharps container program at Penn can be found here.

6. How do I best maintain the refrigerators and freezers in my lab?

Maintaining your lab refrigerators and freezers is a key part of laboratory safety compliance.  If your lab is interested in enhancing your freezer maintenance efforts, we encourage you to participate in the Penn Labs Freezer Challenge.  For additional guidance on maintaining your refrigerator and freezer inventories, click here.

7. How do I safely heat agarose in the microwave?

Heating agarose in the microwave, while a common laboratory procedure, can result in injury if proper precautions are not taken.  EHRS recently developed a new Fact Sheet on Agarose Heating Safety with specific guidance on PPE requirements and recommendations for microwave heating.  For more information on conducting experiments at elevated temperatures, see Fact Sheet: Heating Reactions.

8. Can I store chemicals in my cold room?

Use of hazardous chemicals and compressed gases in cold rooms is only permitted when approved by EHRS.  Since cold rooms are not ventilated, storage of chemicals inside cold rooms can result in high personnel exposure to accumulated gases and vapors.  If the need arises, contact EHRS for assistance with a hazard control plan.  Likewise, liquid nitrogen dewars and dry ice are prohibited in cold rooms as they can release gases that displace oxygen, creating oxygen deficient atmospheres.  See Section VI: Chemical Storage and Transportation in the Chemical Hygiene Plan and SOP: Cryogens and Dry Ice for more information.

9. Can I use my heat resistant gloves for handling cryogens?

No, heat resistant gloves and cryo-gloves are not interchangeable.  An easy way to remember the difference is to “use the blue for blue temps, orange for orange temps!”  For more information, see Fact Sheet: Heating Reactions; Lab Coat, Gloves and Safety Eyewear Policy; and SOP: Cryogens and Dry Ice.

10. How do I dispose of dry ice?

Do not dispose of dry ice or liquid cryogens in the sink or floor drains, as this can damage the plumbing.  Allow cryogens to evaporate/sublime in an open container in a well-ventilated space.  For more information, see SOP: Cryogens and Dry Ice.

11. How do I submit a new, or 3-year renewal, IBC registration?

The Institutional Biosafety Committee (IBC) is now accepting all new and renewal IBC registrations for the generation and/or use of recombinant or synthetic nucleic acids (rsNA) as well as novel gene editing technologies through a new online platform called Penn IBC Electronic Registration System (PIERS). The registration website login page can be found here.  Instructions for registering with the IBC are available on the EHRS website.

Electrical Safety

1. Are there any guidelines for electrical equipment modified or built by lab workers?

Yes! You can view guidelines for electrical equipment that is custom-built or modified here. See the Fact Sheet: Electrical Safety in Labs for more information.

2. Are power strips and extension cords allowed in the lab?

Yes.  Power strips and extension cords may be used in labs; however, there are some restrictions to their use.  See Fact Sheet:  Electrical Safety in Labs for information about these limitations.

3. I heard that there have been a lot of fires caused by hot plates.  What's happening?  

In the past few years, several incidents and near misses involving hot plates have been reported at Penn, including a recent hot plate fire in a BRB cold room (see Hot Plate Malfunctions and Misuse).  The cause of each incident was either electronic malfunction or user error.  Important reminders include: unplugging your hot plate when not in use; using stir-only plates when heat is not required, particularly when stirring non-heat-resistant items; and keeping hot plates out of cold rooms.  Click here for additional guidance.

COVID-19 topics


April, 2020 

While most of you have suspended your laboratory operations and are isolating yourselves at home, we want you to know that EHRS is still here to support both your wellness and your research.

We’re sending this special COVID-19 edition of the Lab Safety Quick FAQs with answers to some of the questions you might have during this period of disrupted operation and working from home.  If you have any other questions or want to talk to an EHRS staff member, please feel free to email us or call our main office number: 215-898-4453.

Physical Hazards

How can I ensure that my home office is set up properly for remote work?

EHRS has recommendations for office furniture, equipment set up, workstation accessories, and exercises to help you transition to an appropriate remote work environment. Visit the Ergonomics page under Penn’s Health & Safety Resources for more information. (Tip:  Expand the “computer ergonomics” menu on the left side of the webpage to view specific topics.) Additional tips can be found in the Guide to Setting up a Safe, Healthy and Productive Home Office and in Ergonomic Considerations in Setting up a Home Office Workspace.



How do I clean my lab if there’s been an exposure to COVID-19?

EHRS has compiled a list of resources and safety information for the COVID-19 virus. See the EHRS Covid-19 Safety Information page for more information.


Lab Safety

What activities can I do remotely to make sure I’m ready to resume lab work quickly and safely upon return to campus?

We’ll be in touch again soon with special guidance for restarting your lab operations.  For now, consider these suggestions for safety and compliance tasks and learning opportunities you can catch up on remotely.



August, 2020

As you continue ramping up your research during the research resumption phase, we want you to know that EHRS is still here to support both your wellness and your research.

We’re sending this special COVID-19 edition of the Lab Safety Quick FAQs with answers to some of the questions you might have during the research resumption phase.  If you have any other questions or want to talk to an EHRS staff member, please feel free to email us or call our main office number: 215-898-4453.


Laboratory Waste

Oops!  The last time our lab disposed of chemical waste was before campus operations were suspended.  What should we do?

Hazardous chemical waste should not be stored in your lab for longer than 3 months.  Therefore, chemical waste that was generated before operations were suspended is now out of compliance with Penn’s Laboratory Chemical Waste Management Guidelines.  Check the date on your chemical waste tags and request a chemical waste pickup using this form if needed.

How do I dispose of my infectious waste?  

Penn has transitioned all infectious waste disposal to Curtis Bay RMW Services.  The procedures for removal vary according to your school or building.  Click here for disposal guidelines and other biohazardous waste disposal resources.  Still have questions?  Contact Assistant Biosafety Officer Marie-Luise Faber at


Lab Safety

Will EHRS be resuming laboratory inspections during the research resumption phase?

Yes.  Two methods will be employed: EHRS-initiated self-inspections and inspector-led building walkthrough surveys.  Self-inspections will be administered via BioRAFT and can be completed by either the PI or the Lab Safety Coordinator.   Building surveys will focus on easily observed lab-worker compliance with COVID-19 safety policies and targeted health/safety procedures.  Your lab will receive a “Lab Safety Issue Requires Your Attention” report via BioRAFT if an EHRS inspector observes compliance issues in your area during building surveys.



Where can I find Biosafety guidance for research with COVID-19 samples or SARS-CoV-2?

Visit Biosafety Guidance for COVID-19 Research Projects for information about appropriate practices, containments, and precautions that must be in place when conducting research involving COVID-19 patient samples and SARS-CoV-2.   



Does EHRS have signage depicting proper mask use that I can share with my lab?

EHRS recently created a “How to Wear a Facemask” poster with proper mask wearing protocol that will be displayed throughout campus buildings.  Click here to download a copy.

What if the nature of our research complicates our ability to comply with physical distancing guidelines? 

Some specialized activities that are critical to research progress require closer contact than that designated by PA State guidelines.  Requests for waivers from the physical distance policy must be approved by your chair and implemented only if and when risk mitigation measures are approved by EHRS.  To submit a Physical Distance Waiver Form, click here.

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