• There are 13 major hazards common to many workplaces.
• Falls to the same surface and to a lower level are the most common types of accidents.
• Ergonomics-related hazards are the most common source of injury in the workplace.

The following list of hazard categories (based on information contained in Oregon Occupational Safety and Health Administration’s (OSHA’s) Identifying and Controlling Hazards workshop materials) may serve as a checklist for employers to begin identifying hazards in the workplace. It is not a comprehensive listing but does cover many of the major hazards common to many workplaces.

1. Falls — The most common types of accidents are falls to the same surface and falls to a lower level. The severity of injury from a fall depends on three factors: velocity of an initial impact, magnitude of deceleration (due to hardness of the surface), and orientation of the body on impact.
2. Impact — Impacts resulting in being struck by and struck against an object may cause serious accidents. The severity of the injury from impacting objects depends on three factors:
   1. Velocity of the impact,
   2. Characteristics of the object (size, hardness, shape, etc.), and
   3. Body part impacted.
3. Mechanical — If it’s mechanical and it moves, it’s a hazard, and employees must be protected. There are as many hazards created by moving machine parts as there are types of machines. Mechanical hazards cause caught-in, caught-on, and crush accidents that can cut, crush, amputate, break bones, strain muscles, and even cause asphyxiation. Mechanical hazard motions include rotating, reciprocating, and transverse. Mechanical hazard actions include cutting, shearing, bending, and punching.
4. Vibration and noise — Tools, equipment, and machinery that vibrate at a low frequency can injure a part of the body or the whole body. However, the most common sound-induced injury is due to high frequency vibration. Low frequency vibration hazards exist in two primary categories:
   1. Segmental vibration — Exposure to equipment that vibrates at various frequencies can affect different parts of the body. For instance, the hands are most sensitive to vibrations at 30–40 cycles per second. Internal organs can be affected at vibrations as low as 4–10 cycles per second.
   2. Whole-body vibration — Very low frequencies can affect the entire body. For instance, truck drivers experience continuous whole-body vibration as they travel. That’s one reason truck driving is considered one of the most hazardous tasks for lower back injuries.
5. Toxics — Virtually all materials may be toxic to some extent. In the workplace a material is toxic if a small quantity can cause an injurious effect, such as tissue damage, cancer, or mutations. It’s important to consider the routes of entry of toxic materials into the human body. There are four possible routes of entry:
   • Inhalation — Breathing in toxics is the most common and dangerous route.
   • Ingestion — Toxics enter through the gastrointestinal tract.
   • Absorption — Toxics pass through skin into the bloodstream.
   • Injection — Toxics may be injected into the body (needles, sharp tools, or work surfaces, etc.); this is the least common, yet most direct route of entry.
6. Heat and temperature — Overexposure to heat and temperature extremes may result in a range of injuries from burns to frostbite. Temperature indicates the level of heat present. The second law of thermodynamics states that heat will flow from an area of higher temperature to one of lower temperature. Heat is produced as a result of chemical reaction, combustion, electrical current, mechanical motion, and metabolism. Heat is transferred by:
   • Convection — Heat is transferred by molecules moving through a fluid, gas, or liquid.
   • Radiation — Occurs when a body’s temperature is above absolute zero.
   • Conduction — Heat is transferred through a substance or between substances without physical movement of the substances themselves.
7. Flammability/Fire — Fire may cause burn injuries. For combustion to take place, the fuel and oxidizer (oxygen) must be present in gaseous form. Flammable materials include:
   • Fuel
   • Solvents
   • Cleaning agents
   • Lubricants
   • Coatings
   • Chemicals
   • Refrigerants
   • Insecticides
   • Plastics
   • Hydraulic fluid
   • Vegetation
   • Wood/paper
   • Fabrics
   • Metals
   • Rubber products
8. Explosives — The results of an explosion may range from minor injury to major catastrophe. Instantaneous release of gas, heat, noise, light, and over-pressure creates a wave front that damages anything in its path. About two billion pounds of explosives are used by industry annually in construction, mining, quarrying, and seismographic work. Explosives may be found in the following forms:
   • Chemicals,
   • Solids,
   • Gases, Dusts,
   • Vapors, and
   • Equipment.
9. Pressure hazards — High- and low-pressure conditions in the workplace can result in injury. Standard atmospheric pressure is 14.7 pounds per square inch (psi). High-pressure gas distribution lines are considered high-pressure when operating at two psi or higher. The American Society of Mechanical Engineers (ASME) rate boilers which operate at more than 15 psi as high-pressure. The pressure in full cylinders of compressed air, oxygen, or carbon dioxide, are over 2,000 psi! Examples of pressure hazards include:
   • Ruptured cylinders — The thrust generated by gas flowing through a puncture or rupture of a cylinder can be 20 times greater than the weight of the cylinder and reach velocity of 50 feet per second in 1/10th of a second! The result: a missile.
   • Whipping hoses and lines — Compressed air and water hoses can kill when end fittings become loose. Such hoses and lines should be restrained by weighting with sandbags at short intervals, chained, clamped, etc. Never try to grab a whipping hose or line: turn off the controlling valve.
   • Water hammer —The effect caused by a sudden stop of liquid flow causing a shock wave (water hammer) that can cause a line rupture. Ever heard a pipe “clang”?
10. Electrical contact — Exposure to electrical current may cause injury or death. The voltage is not so important as the amount of current. It doesn’t take much current to kill. There are five principal categories of electrical hazards:
    • Shock — Electrical shock is a sudden and accidental stimulation of the body’s nervous system by an electrical current. Look for bare conductors, insulation failures, buildup of static electricity, and faulty electrical equipment.
    • Ignition of combustible (or explosive) material — Ignition is usually caused by a spark, arc, or corona effect (ionized gas allows a current between conductors).
    • Overheating — High current creates high heat that can result in fires, equipment burnout, and burns to employees.
    • Electrical explosions — Rapid overheating of circuit breakers, transformers, and other equipment may result in an explosion.
    • Inadvertent activation of equipment — Unexpected startup of equipment and machinery can injure and kill. That’s why we have lockout/tagout procedures.
11. Ergonomics — Improper lifting, lowering, pushing, pulling, and twisting can cause strains and sprains. Ergonomics-related hazards are the most common source of injury in the workplace. About 50% of all claims are related to ergonomics! Ergonomics hazards exist in:
    • The worker – Physical/mental capability, preexisting conditions, etc.
    • The task – Work that includes high force, repetition, frequency, duration, inappropriate posture, and point of operation.
    • The environment – Noise, temperature, humidity, etc.
12. Biohazards — Exposure to plants, animals or their products that may be infectious, toxic, or allergenic may cause illness and disease. People who work with animals, animal products, or animal waste have a greater risk of infection. Biohazard agents include:
    • Bacteria — Simple one-celled organisms that may or may not be harmful.
    • Viruses — Organisms that depend on a host cell for development and reproduction.
    • Fungi — May be small or large (mushrooms) parasitic organisms growing in a living or dead plant or animal matter.
    • Rickettsia — Rod-shaped microorganisms that are smaller than bacteria and depend on a host for development and reproduction.
    • Microorganisms transmitted by fleas, ticks, and lice.
13. Workplace violence — Workplace violence is any violent act that occurs in the workplace and creates a hostile work environment that affects employees’ physical or psychological well-being. A risk factor is a condition or circumstance that may increase the likelihood of violence occurring in a particular setting. Risk factors include:
    • Employee contact with the public;
    • Exchanging money;
    • Selling/dispensing alcohol or drugs;
    • Delivering passengers, goods, or services;
    • Mobile workplace (such as a taxicab or police cruiser);
    • Exposure to unstable or volatile persons (such as in health care, social services);
    • Employees working alone, late at night/early morning, or in small numbers;
    • Employees working in high-crime areas;
    • Employees guarding valuable property or possessions;
    • Employees working in community settings; and/or
    • Employees deciding on benefits, or in some other way controlling a person’s future, well-being, or freedom (such as a government agency).