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Catch Tank
A separate containment vessel intended to receive an emergency discharge from relief devices in the process vessel's vapor space. Catch tanks are usually employed where substantial two-phase relief flow, entrained solids, or reaction mass carryover is expected to occur.
Causal factor (CF)
A major unplanned, unintended contributor to an incident (a negative event or undesirable condition), that if eliminated would have either prevented the occurrence of the incident or reduced its severity or frequency. Also known as a critical causal factor or contributing cause.
Causal factor chart
A sequence diagram that graphically depicts an incident from beginning to end; typically used to organize incident data and identify causal factors.
Cause (in Hazard Evaluation)
In the context of hazard evaluation procedures, an initiating cause.
Cause (Incident)
An event, situation, or condition which results, or could result (Potential Cause), directly or indirectly in an accident or incident.
Cause-Consequence Analysis [Cause-Consequence Diagrams]
A method for illustrating the possible outcomes arising from the logical combination of selected input events or states. A combination of Fault Tree and Event Tree models.
Centerline height
Elevation of plume centerline above ground after plume rise is completed.
Checklist
A list of items requiring verification of completion; typically, a procedure format in which each critical step is marked off (or otherwise acknowledged/verified) as it is performed. Checklists are often appended to procedures that provide a more detailed description of each step, including information regarding hazards, and a more complete description of the controls associated with the hazards. Checklists are also used in conjunction with formal hazard evaluation techniques to ensure thoroughness.
Checklist Analysis
A hazard evaluation procedure using one or more pre-prepared lists of process safety considerations to prompt team discussions of whether the existing safeguards are adequate.
Chemical
Any element, chemical compound or mixture of elements and/or compounds. (OSHA 1994)
Chemical Family
A group of single elements or compounds with a common general name. Example: acetone, methyl ethyl ketone, and methyl isobutyl ketone are of the "ketone" family; acrolein, furfural, and acetaldehyde are of the "aldehyde" family. Importance: Elements or compounds within a chemical family generally have similar physical and chemical characteristics.
Chemical Isolation
The stopping of a flame by means of a chemical suppressant.
Chemical Process Industry
The phrase is used loosely to include facilities which manufacture, handle and use chemicals.
Chemical Reactivity
The tendency of substances to undergo chemical change. (NOAA 2002)
Chemical Reactivity Hazard
A situation with the potential for an uncontrolled chemical reaction that can result directly or indirectly in serious harm to people, property or the environment. The uncontrolled chemical reaction might be accompanied by a temperature increase, pressure increase, gas evolution or other form of energy release.
Chronic
Long-term, usually multiple exposures
Chronic Effect
An adverse effect on a human or animal body, with symptoms which develop slowly over a long period of time. Also, see "Acute". Importance: The length of time that a worker is exposed is the critical factor. Long periods of time pass, with repeated exposure to a chemical, before any ill effects are detected in a worker.
Chronic Exposure
A frequent or continuous exposure to a toxic agent over an unspecified, but generally lengthy, period of time.
Chronic Hazard
The potential for injury or damage to occur as a result of prolonged exposure to an undesirable condition (e.g., smoking, with the potential for causing lung cancer).
Chronic Toxicity
Adverse (chronic) effects resulting from repeated doses of or exposures to a substance over a relatively prolonged period of time. Importance: Ordinarily used to denote effects in experimental animals.
Client
The term used in this text to identify the company issuing the tolling contract to the toller. The toller's client.
Cloud
Any type of pollutant mass moving through the atmosphere.
Code
Written requirements that affect a facility and/or the process safety requirements that apply to a facility. Codes contain requirements that apply to the design and implementation of management systems, design and operation of process equipment, or similar activities. The difference between a code and a standard is that codes have become part of a law or regulation, and therefore their requirements become mandatory within the jurisdictions that have adopted the code requirements in their laws or regulations. This usually occurs at the state level, but may also occur in local or federal laws or regulations.
Combustible
Capable of burning.
Combustible Concentration
Reduction The technique of maintaining the concentration of combustible material in a closed space below the lower flammable limit. This is also called Air Dilution.
Combustible Dust
A finely divided combustible particulate solid that presents a flash fire hazard or explosion hazard when suspended in air or the process specific oxidizing medium over a range of concentrations.
Combustible Liquid
A term used to classify certain liquids that will burn on the basis of flash points. The National Fire Protection Association (NFPA) defines a combustible liquid as any liquid that has a closed-cup flash point above 100 degF (37.8 degC) (NFPA 30). There are three subclasses, as follows; Class II liquids have flash points at or above 100 degF (37.8 degC) but below 140 degF (60 degC). Class III liquids are subdivided into two additional subclasses; Class IIIA: Those having flash points at or above 140 degF (60 degC) but below 200 degF (93.4 degC), Class IIIB: Those having flash points at or above 200 degF (93.4 degC). The Department of Transportation (DOT) defines degcombustible liquids deg as those having flash points above 140 degF (60.5 degC) and below 200 degF (93.4 degC).
Combustion
An exothermic reaction between a fuel and an oxidizer (usually but not necessarily oxygen) that results in a significant temperature rise and usually a visible flame or glow.
Commit to Process Safety
CCPS RBPS Pillar I: Its five Elements represent authentic management commitment to process safety, including nurturing the workforce through strong leadership and process safety activities.
Common cause failure
The occurrence of two or more failures that result from a single event or circumstance.
Common Cause Failure
Concurrent failures of different devices, resulting from a single event, where these failures are not consequences of each other.
Common Cause Failure (CCF)
The failure of more than one component, item, or system due to the same cause.
Common Cause or Common Mode Failure
Failure, which is the result of one or more events, causing coincident failures in multiple systems or on two or more separate channels in a multiple channel system, leading to system failure. The source of the common cause failure may be either internal or external to the systems affected. Common cause failure can involve the initiating event and one or more safeguards, or the interaction of several safeguards.
Common Mode Failure
Concurrent failures of different devices characterized by the same failure mode (i.e., identical faults).
Compatibility
The ability of materials to exist in contact without specified (usually hazardous) consequences under a defined scenario. (ASTM E 1445)
Competency
A PSM program element associated with efforts to maintain, improve, and broaden knowledge and expertise.
Compliance With Standards
CCPS RBPS Element 02: This Element is the system used to provide access to, including acquiring or developing, as needed, process safety technologies, codes, and standards.
Component
An equipment part.
Computer
Equipment composed of hardware (H/W) and software (S/W) that performs basic control functions or process control optimization.
Computerized Maintenance Management System (CMMS)
Computer software for planning, scheduling, and documenting maintenance activities. A typical CMMS includes work order generation, work instructions, parts and labor expenditure tracking, parts inventories, and equipment histories.
Conceptual design
The initial design of a project when basic parameters are known but design details have yet to be developed.
Condensed Phase Explosion
An explosion that occurs when the material is present in the form of a liquid or solid.
Conditional Modifier
One of several possible probabilities included in scenario risk calculations, generally when risk criteria endpoints are expressed in impact terms (e.g., fatalities) instead of in primary loss event terms (e.g., release, vessel rupture). Conditional modifiers include, but are not limited to: probability of a hazardous atmosphere, probability of ignition, probability of explosion, probability of personnel presence, probability of injury or fatality, and probability of equipment damage or other financial impact.
Conduct of Operations
CCPS RBPS Element 15: This Element reinforces that personnel at every level perform their work using operational discipline - doing the right thing at the right time in the right way.
Conduct of Operations (COO)
The embodiment of an organization's values and principles in management systems that are developed, implemented, and maintained to (1) structure operational tasks in a manner consistent with the organization's risk tolerance, (2) ensure that every task is performed deliberately and correctly, and (3) minimize variations in performance.
Confidentiality Disclosure Agreement
An agreement that allows a toller to release information to a third party that would ordinarily be considered proprietary.
Configuration
A set of interconnected equipment forming a system.
Confined Explosion
An explosion of fuel-oxidant mixture inside a closed system (e.g. vessel or building).
Confined Volume Deflagration
A deflagration occurring in an enclosed volume such as a pipe or pressure vessel.
Confinement
Obstacles such as walls and ceilings of a building, vessel, pipe, etc. that serve to limit the expansion of a dispersing or exploding vapor cloud.