HAZARD AND RISK: THE DIFFERENCE SIMPLIFIED.

In the field of Environmental Health & Safety today, the words HAZARD and RISK are the most commonly used words but surprisingly, those key words are often loosely used and erroneously too. Even amongst scholars in post graduate studies. Understanding the relative meaning of these two words and identifying their differences generated heated debate during  classroom studies of some post graduate students. Hence the EHSadvisor's decision to clarify scholars and HSE practitioners alike. 

Though the meaning of the word "Hazard" can be confusing atimes, even amongst scholars. Often the dictionary is not helpful in getting the true definition of the two key words in HSE practice. True, dictionaries do not give specific definitions, or mostly combine it with the term "risk" as definition. For example, even some dictionary definition could be misleading to many. The contemporary  English dictionary defines hazard as "a danger or risk" and that is what actually helps to explain why many people use the terms interchangeably thereby creating confusion.

A.)  WHAT IS A HAZARD?

In trying to define hazard, you have to be mindful of the context you are employing the word.  Though there are many definitions for hazard but the most common definition when talking about Environmental Health and Safety is:

A HAZARD is any source of potential damage, harm or adverse health effects on human,  something or both.

In Environmental Health and Safety, Hazard identification/elimination and risk assessment /control uses the following terms:

1.)  Harm - physical injury or damage to health.

2.)  Hazard - a potential source of harm to a worker, organisation or the environment....

Basically, it is pertinent to point out that a hazard is the potential for harm or an adverse effect. For example, to people it's relating to the health effects in humans.  To organizations, its relates as property or equipment losses, or to the environment).

Sometimes the resulting harm is erroneously  referred to as the hazard instead of the actual source of the hazard. For example, the disease tuberculosis (TB) might be erroneously called a "hazard" by some but, in earnest, the TB-causing bacteria (Mycobacterium tuberculosis) is actually considered the "hazard" or "hazardous biological agent" by professionals. To better clarify what hazard means truly, lets explore more into it by pointing out some types of hazard.

 TYPES OF HAZARDS

A common way to classify hazards is by category:

• Biological Hazards  - Bacteria, viruses, insects, plants, birds, animals, and humans, etc.,
• Chemical Hazards - Depends on the physical, chemical and toxic properties of the chemical,
• Ergonomic Hazards  - Repetitive movements, improper set up of workstation, etc.,
• Physical Hazards  - Radiation, magnetic fields, pressure extremes (high pressure or vacuum), noise, etc.,
• Psychosocial Hazards - Stress, violence, etc.,
• Safety Hazards - unsafe acts,  slipping/tripping hazards, inappropriate machine guarding, equipment malfunctions or breakdowns.

In Environmental Health and Safety, or workplace hazards can come from a wide range of sources. General examples of hazard includes any substance, material, process, practice, etc. that has the ability to cause harm or adverse health effect to a person or property. See Table 1.  

NOTE: Workplace hazards also includes practices or conditions that release uncontrolled energy, like:

1.)  An object that could fall from a height (potential or gravitational energy),

2.)  A run-away chemical reaction (chemical energy),

3.)  The release of compressed gas or steam (pressure; high temperature),

4.)   Entanglement of hair or clothing in rotating machine or equipment (kinetic energy), or

5.)   Contact with electrodes of a battery or capacitor (electrical energy).

Does it really help you? You may please give feedback by using the comment box or send us an email: ehsadvisor@gmail.com

Let's now discuss RISK. 

B.)  WHAT IS RISK?

Risk is simply the chance, or probability that a person will be harmed or experience an adverse health effect if exposed to a hazard. It may also apply to situations with property or equipment loss, or harmful effects on the environment.

In Environmental Health terms,  RISK is the chance, or probability that the environment may suffer degradation or pollution if exposed  to a hazard or a nuisance. 

In Occupational health and safety - Hazard identification and elimination /  risk assessment and control uses the following terms:

Risk – the combination of the likelihood of the occurrence of a harm and the severity of that harm.

Likelihood – the chance of something happening.
Note: In risk assessment terminology, the word “likelihood” is used to refer to the chance or probability of something happening, whether defined, measured, or determined objectively or subjectively, qualitatively or quantitatively, and described using general terms or mathematically (e.g., a probability or a frequency over a given time period).

For example: the risk of developing cancer from smoking cigarettes could be expressed as:

"cigarette smokers are 12 times (for example) more likely to die of lung cancer than non-smokers", or "the number per 100,000 smokers who will develop lung cancer" (actual number depends on factors such as their age and how many years they have been smoking). These risks are expressed as a probability or likelihood of developing a disease or getting injured, whereas hazard refers to the agent responsible (i.e. smoking).

There are factors that influence the degree or likelihood of RISK. They are:

1.)   The nature of the exposure: How much a person is exposed to a hazardous substance  or condition (e.g., several times a day or once a year etc), 

2.)    How the person is exposed: The mode of exposure (e.g., breathing in a vapour; through skin contact), and

3.)    The severity of the effect. For example, one substance may cause skin cancer, while another may cause skin irritation. Cancer is a much more serious effect than irritation.

Does this help your understanding?  Give us a feedback by using the comment  box or send us an email: ehsadvisor@gmail.com.