Skip Navigation
Oklahoma State University

Labeling and Signage Guide

Caution Biohazard Sign

Labels and signage are the cornerstones of Hazard Communications.  They provide the ability to locate and identify laboratory hazards.  The guidance given in this document is intended to provide unambiguous instructions regarding chemical labeling, hazardous waste labeling, entrance signage, chemical storage, location of laboratory safety equipment, and unattended experiments. Specific dimensions and ordering information can be found on the Purchasing Guide sheet.


Proper signage at a laboratory entrance provides important information about the hazards located inside, as well as required PPE. Properly posted signage provides valuable information for responders and visitors, and reminds employees of the hazards they encounter upon entering a laboratory. Signage inside the laboratory designate the locations for laboratory safety equipment, chemical storage, and unattended experiments.  Standardized guidance (below) provides easy identification of hazards and locations of safety equipment.

  • All signs will be conspicuously posted in each area where hazardous chemicals are used or stored. These signs must be written in English.
  • Current laboratory emergency POC information must be posted, which includes POC(s) name and a 24-hour contact number.
  • Signage at laboratory entrances should represent the current laboratory hazards. Signage (Figure 1) should include Global Harmonized System (GHS) hazard pictograms (≥2 inch), emergency contact information, required PPE (≥2 inch), and National Fire Protection Association (NFPA) 704 diamond (≥ 4 inch). Signage should be placed on the wall near the door and not on the laboratory door.

Figure1 GHS(a), PPE(b), and NFPA Diamond (c) Signage

Hazard symbols


  • Laboratory safety equipment must be easy to locate. Locations of the portable fire extinguisher, eyewash station, and safety shower should have signs that are ≥ 6 inches for both height and width (Figure 2).

Figure 2 Example of Eyewash Stations and Safety Shower Signage

Eyewash and safety shower signs


  • Laboratories or work areas with non-chemical hazards such as a magnetic field, radioactivity, biological hazards, heat, cryogenic, molten metals, high electrical energy, etc. will have the appropriate warning signs posted at each entrance.
  • Chemical and hazardous waste storage locations inside the laboratory will be clearly marked with lettering at least 1 inch in height.
  • Chemical storage areas should be labeled using signage at least 1-inch in height (Figure 3). Visitors or responders should be able to easily find chemical storage locations.

Figure 3. Examples for Marking Chemical Storage Areas

Signs for marking acid and oxidizers

  • For unattended experiments, post a notice on or near the experiment. The notice should clearly communicate the emergency shutoff procedures, nature of the hazards, and contact information.


Chemical Labeling

Labeling of chemical containers is fundamental to effective hazard communication. The manufacturer provides compliant labeling for each chemical they sell. However, OSU labeling standards are needed for labeling secondary containers and expiration sensitive chemicals such as peroxide formers. OSU labeling standards are listed below.

  • Manufacturers’ chemical labeling will remain intact and not defaced.
  • All chemicals must be prominently and accurately labeled as to content. The full chemical name must be in legible English. Formulas and abbreviations are not acceptable.
  • Unlabeled chemicals must not be stored or used.
  • Make sure all labels are legible and intact. Periodically check inventory for labels that may have degraded or fallen off. Labels must be on containersthat are designated for chemical pick up.
  • Date all peroxidizable and other chemicals that may become unstable over time. They should display the arrival date, date opened, and latest date tested. Expiration dates may be extended based on testing.
  • All secondary containersmust be labeled with common name, chemical name, and NFPAdiamond (Figure4). Dilutions should be labeled with common name, chemical name, concentration, and NFPA diamond (if hazardous).

Figure 4. Example Labels for  for Secondary (a) and Dilute (b) Chemicals

Labels for hazardous materials

Hazardous Waste Labeling

  • Waste containers must have accurate labeling. A Hazardous Chemical Surplus Tag (Figure 5) must be attached to any unlabeled container or any container whose contents do not match the original manufacturer’s label. The label must clearly and neatly list the chemical or common name of each substance that is at least 1% by volume of the total contents or mixture.

Figure 5. Hazardous Chemical Surplus Tag for Hazardous Waste

Hazardous chemical surplus tag

  • Carcinogens or highly toxic substances (0.1% or more by volume) must also be listed. Any amount of a heavy metal (e.g. As, Ba, Cd, Cr, Hg, Ni, Se, Ag, Th) greater than 1 part per million (1 ppm) in the container must be listed.
  • Indicate the strength or concentration of the substance where applicable. Example: hydrochloric acid may have strength of 10%, 28%, or 38%.
  • Do not use chemical formulas, chemical symbols, chemical equations, or abbreviations. All labels must be written in English.
  • Indicate the physical and/or health hazards of the substance, if known.
  • Indicate the name of the building, room, and PI or person responsible for generating the waste (or someone with direct knowledge of the process).
  • In the instances of time-sensitive substances such as ethers, the date of container opening or initial accumulation will be included on the form.
  • Remove or obliterate any other labels or wordings not related to the current substance.
  • Do not allow the creation of "UNKNOWNS" through the lack of secure labeling.