Staying aware of your laboratory’s signage is paramount to your day-to-day safety. Since you and your colleagues are in an environment populated with chemicals, instruments, flammable objects and things that can be easily broken, it’s vital that the workplace is signposted properly to warn workers and visitors of potential hazards.

From physical hazards to specific agents, it’s imperative your environment is appropriately flagged. Depending on the research being conducted, here are the following symbols that should be posted throughout your laboratory and workplace.

General Warning

If you see this sign, then it’s a broad, catch-all reminder that potential hazards are present in your workplace and you should work safely and in accordance with your lab’s regulated procedures. Often found on equipment, doorways, and cupboards.

Biohazard

Stamped on things such as fridges and freezers that contain materials such as blood samples that run the risk of being contaminated with biohazardous material. If a lab is working with infectious agents, this sign should mark the area accordingly and workers should wear the appropriate protection.

Areas signposted with this symbol should be cleaned and decontaminated regularly, while managers must have an effective exposure control plan in place in case of emergency.

Explosive Material Hazard

Chemicals with explosive properties should be labelled with this symbol. This includes unstable explosives that can result in chemical reactions that cause damage, self-reactive substances and mixtures that cause fire or explosions in the absence of air, as well as organic peroxides. 

Flammable Material

Any substances that ignite and burn in the air need to be labelled with the flammable and combustible symbol; this includes solvents and cleaning materials that are often used in the lab’s upkeep rather than day-to-day research. Keep materials like this away from open flames, heat and anything that can cause materials to ignite. 

Toxic Material

This sign denotes the presence of substances that can prove harmful to individuals if inhaled and ingested or if contact is made with the skin. The effects of the toxic material depend entirely on the specific material and its concentration and how an individual is exposed to it, so materials should be properly marked. 

Non-Ionising Radiation

Sources of non-ionising radiation should be clearly marked. This includes the spectrum of ultraviolet, visible light, infrared, microwave, radio frequency, and extremely low frequency. Your lab should minimise exposure to non-ionising radiation through biological safety cabinets, personal protective equipment and engineering controls.

Ionising Radiation

An indication of ionising radiation i.e. radiation that carries enough energy to liberate electrons from atoms or molecules, thus ionising them. This is produced by things such as X-ray equipment, medical beam cannons and particle accelerators. The entry of radionuclides into the body must be kept as low as possible so the appropriate protective clothing must be worn.

Low Temperature

Low temperature or cryogenic hazards should be appropriately marked with this symbol. Since they’re often lower than freezing point and stored with things like liquid nitrogen, personal protective equipment must be worn. This includes thick rubber gloves that go to the elbows, long pants, closed-toe footwear, a rubber apron and face shields.

UV Light Hazard

Ultraviolet light areas are to be stamped with this symbol since exposure to UV light can range from ulcerations on the skin to cancer of the skin itself.

Oxidising Material

Since oxidising materials create oxygen and other oxidising substances, it’s important they’re correctly signposted. The oxygen made by these materials can increase the chance of fires and even explosions in the absence of air, while the toxic and corrosive properties they have can be harmful to the skin. Common oxidising materials include bromine, chlorates, nitrates, perchloric acid and peroxides.

Laser Beam Hazard

Signalling that hazards from laser beams are present, lab staff must wear the correct protective clothing, since direct exposure to laser beams can damage the eyes and skin, while non-flammable clothing should also be worn at all times, whether or not the laser is in operation.

Optical Radiation Hazard

Ultraviolet radiation, visible light and infrared radiation all fall under the umbrella of optical radiation. This type of radiation requires correct protective clothing and equipment when in use. In particular, radiation-producing lasers must have the beam path for the laser system enclosed, and users should double check to ensure there are no unwanted reflections before using the laser.