Lab Safety

Safety Hazards in the Lab

Physical Hazards of Chemicals

Flammable, Combustible and Explosive solids, liquids, and gasses Flammable, combustible and explosive materials can vaporize and form flammable mixtures with air when in open containers, when leaks occur or when heated, or may become flammable with certain catalysts.
Oxidizing solids, liquids and gasses An oxidizer in itself may not necessarily be combustible, may, generally by yielding oxygen, cause or contribute to the combustion of other material.
Gasses Under Pressure Compressed gases can be toxic, flammable, oxidizing, corrosive, inert or a combination of hazards. In addition to the chemical hazards, compressed gases may be under a great deal of pressure.
Self-Reactive (unstable) Substances Self-reactive substances are thermally unstable liquids or solids liable to undergo a strongly exothermic thermal decomposition even without participation of oxygen (air).
Water Reactive Materials Water reactive substances are dangerous when wet because they undergo a chemical reaction with water. This reaction may release a gas that is either flammable or presents a toxic health hazard.
Pyrophorics A pyrophoric is liable to ignite after coming into contact with air, even in small quantities.
Organic Peroxides An organic peroxide may be considered a derivative of hydrogen peroxide, where one or both of the hydrogen atoms have been replaced by organic radicals. The term also includes organic peroxide formulations (mixtures). Such substances and mixtures may: be liable to explosive decomposition; burn rapidly; be sensitive to impact or friction; react dangerously with other substances. Peroxides can occur in virtually any kind of organic chemical, however, certain chemicals are particularly prone to peroxide formation and pose special hazards. May also be light sensitive.
Corrosive A corrosive material is a highly reactive substance that causes obvious damage to living tissue or to metal. Corrosives act either directly, by chemically destroying the part (oxidation), or indirectly by causing inflammation.
Cryogens A cryogenic a substance used to produce very low temperatures. A synonym is "refrigerant".
Radioactive Isotopes  


 Health Hazards of Chemicals

Acute Toxicity

Acute toxicity describes the adverse effects resulting from a single exposure to a substance.

Skin, Respiratory & Eye Corrosion/Damage

Changes to the skin tissue or damage to the eye that are not reversible

Skin, Respiratory & Eye Irritation

Irritants are not corrosive, but which cause reversible inflammatory effects on living tissue by chemical action at the site of contact.

Skin and Respiratory Sensitization

Skin sensitizer means a substance that will induce an allergic response following skin contact. A respiratory sensitizer means a substance that induces hypersensitivity of the airways following inhalation of the substance.

Target Organ Toxicity

Certain organs or systems can be affected by either single or multiple exposures to a substance. These include nephrotoxins, neurotoxins, hematoxins, etc.


A mutagen is a substance or agent that causes an increase in the rate of change in genes (subsections of the DNA of the body's cells). These mutations can be passed along as the cell reproduces, sometimes leading to defective cells or cancer. Examples of mutagens include certain biological and chemical agents as well exposure to ultraviolet light or ionizing radiation.


An asphyxiant is a substance that can cause unconsciousness or death by suffocation (asphyxiation) or aspiration. Aspiration is the entry of a liquid or solid directly through the oral or nasal cavity, or indirectly from vomiting, into the trachea and lower respiratory system. Aspiration toxicity includes severe acute effects such as chemical pneumonia, varying degrees of pulmonary injury or death following aspiration.


Carcinogen means a chemical substance or a mixture of chemical substances which induce cancer or increase its incidence.

Reproductive Toxins

Reproductive toxicity includes adverse effects on sexual function and fertility in adult males and females, as well as developmental toxicity in offspring.

 Lab Equipment Hazards

Cuts, scrapes, bruises The most common lab injuries come from contact with sharp equipment, slips, trips, falling objects, broken glass, etc.
Electrical Hazards Electrical hazards include use of high-voltage equipment, wet environments, harsh environments that may deteriorate insulation, and automatically starting equipment.
Mechanical Hazards Some equipment has moving parts that may present pinching or crushing hazards, may catch loose clothing, or may vibrate or move while running.
Burns Fires, hot plates, extreme cold, and hot equipment are common in labs and may cause burns without proper precautions.
Flying Particles Flying particles and chemicals may occur frequently and without warning from various lab equipment and operations
Intense Light UV and laser light may cause burns or eye damage
Vacuum/Pressure Containers placed under high vacuum or pressure can become hazardous in certain circumstances
Noise Equipment may generate enough noise to cause damage to hearing or prevent communications in an emergency situation. Also, high frequency sound may cause hearing damage.
Electric and Magnetic Fields Electric and magnetic fields (EMFs) are invisible lines of force associated with the use of high-voltage electric power. Health effects are uncertain, but individuals with pacemakers or metallic implants should take precautions.
Batteries Some batteries contain corrosive liquids or may generate hydrogen gas while charging. Others can explode if overcharged or contain heavy metals.
Radiation Radioactive sources may be present in certain analytical equipment


Workplace Environmental Hazards

(Stress or Strain)

Certain tasks in the lab may involve heavy lifting or repetitive motions that, over time, may lead to musculoskeletal disorders
Confined Spaces While rare in lab settings, confined spaces hazards may occur in certain circumstances. A confined space is a space that 1) is large enough for an employee to enter and perform assigned work, 2) has a limited or restricted means of entry or exit, and 3) is not designed for continuous employee occupancy
Respiratory Hazards In situations where engineering controls are not sufficient to provide a safe atmosphere, the use of respirators may be necessary.
Hot/Cold Environments Work in refrigerated environments or field work may present certain safety hazards from exposure to temperature extremes.
Elevated Platforms/Ladders Fall protection may be necessary under certain circumstances.


Biological Hazards

Exposure to Infectious Agents, Pathogens or Toxins
Exposure to Laboratory Animals


Routes of Entry

Skin Skin contact with a chemical may result in a local reaction, such as a burn or rash, or absorption into the bloodstream, which could allow the chemical to cause toxic effects on other parts of the body.
Eyes Chemical contact with eyes can result in painful injury or loss of sight.
Inhalation The respiratory tract is the most common route of entry for gases, vapors, particles, and aerosols (smoke, mists and and fumes). These materials may be transported into the lungs causing localized effects, or be absorbed into the bloodstream.
Ingestion Toxic substances can enter through the gastrointestinal tract. Although direct ingestion of a laboratory chemical is unlikely, exposure may occur as a result of ingesting contaminated food or beverages, touching the mouth with contaminated fingers, or swallowing inhaled particles which have been cleared from the respiratory system.
Injection Injection bypasses the protection provided by skin and provides direct access to the bloodstream and internal organs. Injection may occur through mishaps with syringe needles, when handling animals, or through accidents with pipettes, broken glassware or other sharp objects that have been contaminated with toxic substances.


Page last modified March 14, 2014