Chapter 2: General Laboratory Safety

Revised January 2023


An unorganized, cluttered laboratory increases the likelihood of chemical spills and splashes due to tripping or knocking over chemical containers. Safety equipment such as fire extinguishers, safety showers, and eyewashes can prevent or minimize harm to personnel; however, they are ineffective if access is blocked. Organize your laboratory so that clear walkways are provided, with designated storage areas for chemicals and hazardous waste; avoid clutter that can prevent access to safety equipment or which can lead to chemical spills or other mishaps.

Laboratory Assessments

EH&S will perform periodic health and safety assessments of chemical laboratories and chemical storerooms. The goal of these assessments is to identify areas where laboratory safety can be improved. Laboratory assessments are most effective when the laboratory supervisor and other laboratory workers participate with EH&S. Written recommendations resulting from these assessments will be given to the laboratory supervisor and Department Chair.

Each individual laboratory should perform self-assessments of their laboratory at least once per year. A lab assessment checklist is available to assist in this process. The purpose of this self-assessment is to allow each laboratory to self-identify and correct safety and health weaknesses. A record of these laboratory self-assessments should be maintained to document the findings and corrective actions, and so that reoccurring problems can be identified.

Personal Chemical Hygiene

Good personal chemical hygiene habits minimize chemical exposure. Consuming food and beverages in laboratories or chemical storage areas is not permitted since this practice increases the likelihood of chemical exposure by ingestion. For the same reason, do not store food or beverages in laboratories (including refrigerators) or chemical storage areas. Washing your hands frequently will minimize chemical exposure through ingestion and direct contact with the skin. Always wash hands before eating, drinking, smoking, or applying cosmetics.

Basic Chemical Handling Procedures

  • KNOW THE HAZARDS OF THE CHEMICALS YOU ARE WORKING WITH! Consult the Safety Data Sheet (SDS) or other appropriate references prior to using a chemical with which you are unfamiliar (see Chapter 15).
  • Minimize exposure to all chemicals regardless of toxicity or their familiarity. Most laboratory chemicals have not been fully characterized with respect to their toxicity; therefore, it is prudent to implement procedures that will reduce the likelihood of exposure. Skin contact should always be avoided. Avoid inhalation of chemicals; never "sniff" to test chemicals.
  • Wear appropriate eye protection at all times. At a minimum, safety glasses are required whenever operations involving chemicals are being performed.
  • Minimize chemical exposure through consistent and proper use of laboratory hoods and personal protective equipment.
  • Communicate with others in the building when working alone in the laboratory; let them know when you arrive and leave. Avoid working alone in the laboratory when handling hazardous chemicals, carrying out chemical reactions, or performing other higher risk operations.
  • Use cautious judgment when leaving unattended operations: i) post signs to communicate appropriate warnings and precautions, ii) anticipate potential equipment and facility failures and implement mitigative measures, and iii) provide containment and/or shielding for release of hazardous chemicals.
  • Assume that unknown materials are toxic, and that a mixture is more toxic than its most toxic compound.
  • Know the location and proper use of emergency equipment, such as safety showers and fire extinguishers, and maintain clear access to this equipment.
  • Do not use mouth suction for pipetting or siphoning.
  • Label all chemical containers with the identity of the contents; primary hazards and chemical concentration must also be included on long term secondary containers.
  • Use appropriate safety carriers (secondary containment) when transporting chemicals either inside or outside of the building.

Moving/Transporting Chemicals either Inside or Outside a Building

If a laboratory needs to move a few chemicals either inside or outside a building, follow the guidelines below. If a laboratory needs to move a large number of chemicals or the entire lab, STOP and contact the University CHO for appropriate guidance.

  • Lab personnel are responsible for using appropriate safety carriers (secondary containment) when transporting chemicals.
  • Carts are preferred for transporting chemicals.
  • The appropriate Personal Protective Equipment (PPE) needed to safety handle the chemicals being transported should be moved with the chemicals. In the event of a spill the PPE should be donned.
  • Chemicals must be segregated as flammables, oxidizers, acids, or bases, with liquids and solids in each hazard class segregated and in separate transport containers.
  • Leak-proof plastic containers are recommended for the transport of liquids.
  • Liquid containers should be cushioned to prevent breaking during transport.
  • Moving Gas Cylinders: see Chapter 8 of this CHP, subsection gas cylinders
  • 55 gallon drums: Lab personnel are not permitted to transport 55 gallon drums between rooms inside a building or between buildings. Contact the University CHO to arrange transport of 55 gallon drums.

Moving Large (150 or 300 Liter) Cryogenic Liquids: see Chapter 8 of this CHP, subsection cyrogens

  • If a Spill Occurs Out of Containment Outside of a Lab Room:
    • Don the appropriate PPE
    • Stop and contain the spill
    • Stay in the area, do not permit others near the area
    • Contact EH&S on the 24 hour line, 327-5050 and report the chemicals and quantity spilled outside of a laboratory room and request assistance.
    • Remain in the area after EH&S arrives.
    • Also refer to Chapter 19 of this CHP, subsection Chemical Spills

Prior Approval of Operations

Each laboratory supervisor should identify operations that require their prior approval before the procedure is initiated. The designated operations will normally be those non-routine operations that are higher risk; however, more routine operations can also be included. Some situations that should be considered for prior approval include:

  • A new laboratory procedure that represents greater than routine risk (especially if it differs substantially from procedures already in use).
  • New work involving particularly hazardous substances.
  • Operations where it is likely that there will be significant exposure to a chemical or other hazard (biological, physical, etc.).
  • There is a procedural change that significantly increases the overall hazard of the procedure.
  • Unattended operations that represent significant likelihood of fire, explosion, or exposure to personnel if a malfunction were to occur (such as a utility outage, runaway reaction, or chemical spill).

Operations that require prior approval should be documented in laboratory-specific standard operating procedures. It is also recommended that approval by the laboratory supervisor be documented through the use of a dedicated “prior approval” form or an entry in a research notebook.

Laboratory Entrance Signs

The entrance to each laboratory or chemical storage area must be posted with the name and phone number (office phone number and after-hours number) of the laboratory supervisor, with designation as the primary emergency contact. If there is another faculty (academic or administrative) member who is knowledgeable of laboratory operations, that individual can be listed as an alternate emergency contact, along with his or her office phone number and after-hours phone number. If an alternate emergency contact is not available, EH&S will be listed. Entrance signs must also provide hazard information related to chemicals stored in the room.

EH&S maintains entrance signs for each laboratory that indicate the primary and secondary emergency contacts, chemical hazard information, and other emergency information. Contact one of the EH&S chemical hygiene contacts listed in Chapter 1 to request an entrance sign or to update the entrance sign for your laboratory.

Chapter 3: Written Standard Operating Procedures