YUAL Safety & Policies

Safety Discussion 

The purpose of this discussion is to review basic safety practices and procedures for laboratory work, and outline the appropriate actions to follow in the event of an emergency.

Additional information is available from Yale Environmental Health and Safety (EHS): ehs.yale.edu

Emergency Contact Numbers

  • Medical, Fire, Police: 911 or 203-432-4400
  • EHS Emergency Line: 203-785-3555
  • Yale Health Acute Care: 203-432-0123
  • Yale EHS Main Phone: 203-785-3550

Introduction to Safe Science

  • Safety is an integral and important component of laboratory sciences. Good science is safe science.
  • Everyone at Yale is responsible for safety. This includes instructors, teaching fellows, and students – all of us!
  • Always plan ahead for lab exercises, and incorporate safety into all experimental procedures.
  • Science includes raising concerns and asking questions. Please ask for assistance if you are unsure about a particular step or process in the experiment.
  • Yale EHS is also here to help – contact them for assistance anytime.

Appropriate Lab Clothing

  • Dress appropriately for working in a lab.
  • Always wear long pants and closed toe solid top shoes. Never wear shorts, skirts or sandals in the lab.
  • Safety glasses are required be worn when working in a laboratory at Yale.
  • Wear a lab coat for work involving hazardous materials.
  • Wear chemically-resistant gloves when handling hazardous materials. Although nitrile exam style gloves are adequate for most operations, heavy utility-grade gloves should be worn for tasks where skin contact is likely. Additional information on glove and other PPE selection available from ehs.yale.edu.
  • Tie long hair back/up.
  • Remove lab coats and other PPE and wash your hands when leaving the lab.
  • Wearing contact lenses during wet labs is strongly discouraged. 

Emergencies – General Information

  • Note the locations of the nearest exits from the room and building.
  • Note the location of the nearest safety shower, emergency eyewash, spill response supplies, phone, and fire alarm pull station.
  • If you are involved in or witness an incident or accident, immediately notify the instructor, teaching fellow, and others in the area.
  • For significant hazardous materials spills, medical emergencies, or fires of any size, pull the nearest fire alarm box or dial 911 from any phone immediately.
  • When making an emergency notification, give the dispatcher as much information as possible, including phone, location, incident type, and whether anyone has been injured.


  • In the event of a fire alarm, turn off equipment, reactions, and electrical supplies and exit the building. Stage together near the building and await the “all clear” from the police, fire department, or other emergency responders before re-entering.
  • In the event of an actual fire, activate the building fire alarm from the nearest fire pull station, or call for help by dialing 911 from any phone. Give your location, name, and a description of the fire.
  • If the fire is small and contained, call for help or pull the alarm station before even attempting to use the fire extinguisher, and only use a fire extinguisher if you have been trained how to do so.
  • Fire extinguisher training is available at firemarshal.yale.edu

Safety Showers and Eyewashes

In the event of splash or contamination to the eyes or body:

  • Immediately flush the affected area with a deluge of water for 15 minutes.
  • Flush the eye at eyewash while holding eyelids open.
  • For splashes to the body, remove contaminated clothing while using emergency shower.
  • Always followup with medical evaluation.
  • Call 911 for emergency medical services and transportation to the hospital.
  • Less serious splashes or contamination – follow up with Yale Student Health or Acute Care (Yale Health Services – 55 Lock St. 203-432-0123).

Basic Laboratory Safety

  • Never work alone in the lab.
  • Eating and drinking, as well as storage of food, is prohibited in all labs.
  • Plan your experiments ahead of time, use written procedures, and keep notes during the work. Do not procedure if you are unsure of any step or procedure – ask!
  • Scale-ups require review and approval of the instructor before initiating.
  • Use tongs or heat resistant gloves when handling hot objects.
  • Avoid the use of sharps such as needles or glass pasteur pipettes wherever possible. If you must use needles, never recap them after use - instead dispose in the needle box.
  • Use a fume hood for transfers, reactions, and other work with volatile or hazardous materials.
  • Clean lab work surfaces and equipment at the end of your experiment or procedure.
  • Avoid using open flames if possible, instead use a hot plate, heating mantle, or heating block.
  • Never overload electrical circuits, and keep extension cord use to a minimum.
  • When working with concentrated acids, remember: always add acid to water.
  • Use a plastic blast shield and wear a faceshield and flame resistant lab coat in addition to standard lab safety glasses whenever performing reactive work.
  • Date-label all time sensitive compounds (e.g., ethers, concentrated peroxides, picric acid, perchloric acid) and dispose once out-dated.
  • Be suspicious of any reagent container that has visible residue or crystals around the cap, and seek advice from the instructor before opening.
  • Remove gloves and wash hands with soap and water before leaving the lab.

Waste Disposal

The proper collection and disposal of laboratory wastes has important safety, environmental, financial, and legal implications for you and the University. Please refer to the Laboratory Waste Disposal Tool (ehs.yale.edu) for information on disposal of hazardous materials.

  • Do not mix waste from incompatible hazard classes.
  • Collect wastes in compatible containers in a central area of the lab, using a tray or bin below as secondary containment in the event of a spill or leak. Keep track of the materials placed into waste containers so that the filled container can be characterized prior to disposal.
  • All containers used to collect hazardous chemical waste must be labeled as “Hazardous Waste” immediately before adding the waste chemical to the container. All constituents and percentages of each must be identified on the label.
  • Dispose of waste chemicals in a timely manner to avoid lengthy accumulation periods and minimize the potential for damage to storage containers.
  • Do not put “Sharps” (e.g., syringes and needles, scalpels, razor blades, glass pipettes, and other objects that can easily puncture skin) in the regular trash.

Additional Training

Work with human blood, bodily fluids, unfixed human tissues, human or non-human primate cell cultures, human pathogens, or radioactive materials requires additional safety training. Certain field work with the potential for exposure to infected arthropods or wild mammals may also require additional training and acknowledgement of risks. Contact your EHS Safety Advisor for more information.