Data processing: measuring – calibrating – or testing – Measurement system – Statistical measurement
Reexamination Certificate
2002-08-02
2004-05-25
Hoff, Marc S. (Department: 2857)
Data processing: measuring, calibrating, or testing
Measurement system
Statistical measurement
C702S034000, C702S081000, C702S082000, C702S108000, C702S116000, C702S123000, C702S182000
Reexamination Certificate
active
06741951
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to safety analysis of a product or system. More particularly, it relates to a method for conducting an analysis of a product or a system to evaluate risk(s) to personnel or equipment and identify mitigating conditions that may control or avoid such risks.
A variety of different processes have been used in the past to determine safety of various systems. These processes are often introduced after the occurrence of a catastrophic event or after the occurrence of a consistent series of events resulting in harm to personnel.
Preliminary hazard assessment (PHA) had origins from a combination of generic industry hazard checklists. These checklists required identification of inherent hazards, which a test applicant must address specifically in a subsequent review session. One of the shortcomings of this process involves the task of addressing the risk that was left entirely to an applicant—in any style deemed appropriate to the applicant's knowledge. Thus, the documentation of the approach and the results greatly varied and required additional time and resources to ensure completeness. Also, gathering information with respect to critical hazardous features and combinations depended on an initial reviewer's expertise.
Hazard characterization and personal safety analysis involves examination of hazards associated with a job or a task. In this technique, workers are grouped so that risks and exposures experienced by any member of a group are representative of the group as a whole. Information about the nature of a workplace, equipment and materials used, and the tasks to be performed may be considered as the basis of this step.
In another approach, a preliminary assessment of hazards require a minimal effort to identify the inventory of hazardous materials to perform an initial hazard categorization. Reviewing basic facility information on intended facility operations and using estimates of materials may lead to an acceptable assessment. Hazard characterization also uses information from existing hazard analysis documentation such as, for example, safety analysis reports, process hazard analysis, job safety analysis (JSA), and the job hazard analysis.
Hazards are identified and resultant risks are assessed by considering probability of occurrence and severity of consequence. System safety is part of the overall program risk management decision process. Severity is an assessment of the worst potential consequence, defined by degree of injury or property damage, which could occur. For example, hazard severity may be categorized as: catastrophic, critical, marginal and negligible.
Factors for identification of hazards include, for example, (a) identification of hazardous components, (b) identification of hazardous operating conditions, (c) safety related interface considerations, (d) environmental constraints including operating environments, (e) training and certification pertaining to hazardous and safety critical operations and maintenance of hazardous and safety critical systems, etc.
Hazardous operations review analysis is performed to evaluate activities for hazards or risks introduced into a system by operational and support procedures and also to evaluate the adequacy of operational and support procedures that are used to eliminate or control identified hazards or risks. Typically, hazards are identified and evaluated by considering such criteria as plan system configuration and state at each phase of an activity; facility interfaces; supporting tools including software controlled automatic test equipment, to name but a few. Human factor(s) may be considered as an element of the total system, receiving both inputs and initiating outputs during the conduct of the analysis.
Safety efforts related to the hazardous operations review process focus primarily on the safe operation of a system. This process focuses on the operational phase of the system with specific emphasis on single-point failures. This process is not easily implemented for multiple system and multiple point failures.
There is a need for a structured, standardized and efficient methodology for conducting a thorough analysis of a single product or a complex system to evaluate risk(s) to personnel and equipment, and identify mitigating factors to reduce the identified risk(s).
BRIEF DESCRIPTION OF THE INVENTION
The present invention provides a structured, standardized and efficient methodology for conducting a effective analysis of a product or a complex system to evaluate the risk to personnel and equipment safety. Further, the present invention identifies and implements mitigating factors to control possible risks to personnel and equipment.
The safety review process methodology of the present invention combines preliminary hazard assessment, hazardous operations review, and accident scenario review processes into a unique systemic series of actions. The present method further provides the flexibility to invoke and execute the safety review process at almost any stage in the development of a new product, or the use of an existing product.
Specifically, the present method analyzes, using a preliminary hazard assessment, a system or product to identify inherent hazards associated with the system or product. Of the inherent hazards, those hazards that are safety-comprising are identified in a hazardous operations review. Safety-compromising hazards are analyzed to rate the severity of the potential unsafe condition. Predetermined and established operating parameters of the product are considered, along with deviations from those established operating parameters. With respect to a deviation for an operating parameter, the possible safety consequences of the deviation are considered. This process is repeated until all the factors contributing to credible single-point failures and unsafe conditions are considered.
A system or product is also evaluated for a multi-system or multi-point failure using an accident scenario review, if an identified unsafe condition is of sufficient severity, is associated with a plurality of components of the system or is associated with various distinct systems. In this case, a thorough analysis of mitigating factors is performed to stop progression of the risk(s). Additional control measures are adopted to further reduce the likelihood of potential hazards from occurring. This process is repeated until the overall risk level is found to be acceptable.
An embodiment of the present invention is a method for analyzing a system for safety to personnel or other systems, said method comprising: a) segmenting a product into subcomponents for hazard review; b) identifying at least one operating parameter of a first subcomponent of said product; c) identifying an inherent hazard of said first subcomponents based on an analysis of the at least one operating parameter; d) identifying features of the structure or operation of the subcomponent corresponding to the inherent hazard; e) identifying modifications or controls for the identified features which would mitigate the inherent hazard; f) prioritizing the identified features with respect to the effect that each of said features has on safety of the product; g) identifying current documentation that defines the structure or operation of the subcomponent; h) including in the current documentation, a safety audit procedure that identifies one or more of said prioritized features for inspection, and i) determining whether an unsafe condition could result from the inherent hazard after step (e).
This embodiment of the invention may further include a method, wherein an unsafe condition has been determined, for conducting a hazardous operation review comprising: j) identifying at least one contributing factor to the unsafe condition, where said factors are selected from a group comprising at least one of: a design deviation of the subcomponent, an operating mode of the subcomponent, and a mode of personal interaction with the subcomponent; k) generate a matrix correlating the identified features and
Kaufman Eric Stephen
Starr William Michael
Whaling Kenneth Neil
General Electric Company
Hoff Marc S.
Nixon & Vanderhye P.C.
Tsai Carol S W
LandOfFree
Method for performing a hazard review and safety analysis of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for performing a hazard review and safety analysis of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for performing a hazard review and safety analysis of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3240520