Process Hazard Analysis
Encyclopedia
Process Hazard Analysis (or, Process Hazard Evaluation) is a set of organized and systematic assessments of the potential hazard
s associated with an industrial process
. A PHA provides information intended to assist managers and employees in making decisions for improving safety
and reducing the consequences of unwanted or unplanned releases of hazardous chemicals. A PHA is directed toward analyzing potential causes and consequences of fire
s, explosion
s, releases of toxic or flammable chemicals and major spills of hazardous chemicals, and it focuses on equipment, instrumentation, utilities, human actions, and external factors that might impact the process.
There are a variety of methodologies that can be used to conduct a PHA, including but not limited to:
Checklist, What if?, What if?/Checklist, Hazard and Operability Study, Failure Mode and Effects Analysis
, Process Flow Failure Modes (PFFM) Analysis, Layer of Protection Analysis http://www.absconsulting.com/svc_opRisk_LOPA.html, and Fault Tree Analysis
.
The selection of a methodology to use depends on a number of factors, including the complexity of the process, the length of time a process has been in operation and if a PHA has been conducted on the process before, and if the process is unique, or industrially common.
In the United States
, the use of PHAs is mandated by the Occupational Safety and Health Administration
(OSHA) in its Process Safety Management
regulation for the identification of risks involved in the design
, operation, and modification of processes that handle highly hazardous chemicals.
Hazard
A hazard is a situation that poses a level of threat to life, health, property, or environment. Most hazards are dormant or potential, with only a theoretical risk of harm; however, once a hazard becomes "active", it can create an emergency situation. A hazard does not exist when it is not...
s associated with an industrial process
Industrial process
Industrial processes are procedures involving chemical or mechanical steps to aid in the manufacture of an item or items, usually carried out on a very large scale. Industrial processes are the key components of heavy industry....
. A PHA provides information intended to assist managers and employees in making decisions for improving safety
Safety
Safety is the state of being "safe" , the condition of being protected against physical, social, spiritual, financial, political, emotional, occupational, psychological, educational or other types or consequences of failure, damage, error, accidents, harm or any other event which could be...
and reducing the consequences of unwanted or unplanned releases of hazardous chemicals. A PHA is directed toward analyzing potential causes and consequences of fire
Conflagration
A conflagration or a blaze is an uncontrolled burning that threatens human life, health, or property. A conflagration can be accidentally begun, naturally caused , or intentionally created . Arson can be accomplished for the purpose of sabotage or diversion, and also can be the consequence of...
s, explosion
Explosion
An explosion is a rapid increase in volume and release of energy in an extreme manner, usually with the generation of high temperatures and the release of gases. An explosion creates a shock wave. If the shock wave is a supersonic detonation, then the source of the blast is called a "high explosive"...
s, releases of toxic or flammable chemicals and major spills of hazardous chemicals, and it focuses on equipment, instrumentation, utilities, human actions, and external factors that might impact the process.
There are a variety of methodologies that can be used to conduct a PHA, including but not limited to:
Checklist, What if?, What if?/Checklist, Hazard and Operability Study, Failure Mode and Effects Analysis
Failure mode and effects analysis
A failure modes and effects analysis is a procedure in product development and operations management for analysis of potential failure modes within a system for classification by the severity and likelihood of the failures...
, Process Flow Failure Modes (PFFM) Analysis, Layer of Protection Analysis http://www.absconsulting.com/svc_opRisk_LOPA.html, and Fault Tree Analysis
Fault tree analysis
Fault tree analysis is a top down, deductive failure analysis in which an undesired state of a system is analyzed using boolean logic to combine a series of lower-level events...
.
The selection of a methodology to use depends on a number of factors, including the complexity of the process, the length of time a process has been in operation and if a PHA has been conducted on the process before, and if the process is unique, or industrially common.
In the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, the use of PHAs is mandated by the Occupational Safety and Health Administration
Occupational Safety and Health Administration
The United States Occupational Safety and Health Administration is an agency of the United States Department of Labor. It was created by Congress of the United States under the Occupational Safety and Health Act, signed by President Richard M. Nixon, on December 29, 1970...
(OSHA) in its Process Safety Management
Process Safety Management
Process Safety Management is a regulation, promulgated by the U.S. Occupational Safety and Health Administration . A process is any activity or combination of activities including any use, storage, manufacturing, handling or the on-site movement of Highly Hazardous Chemicals as defined by OSHA...
regulation for the identification of risks involved in the design
Process design
Process design is the design of processes for desired physical and/or chemical transformation of materials. Process design is central to chemical engineering and it can be considered to be the summit of chemical engineering, bringing together all of the components of that field.Process design can...
, operation, and modification of processes that handle highly hazardous chemicals.