Improving Safety Through Engineering Assessments for Change in Location Class

2016 ◽  
Author(s):  
Shahani Kariyawasam ◽  
Mohammad Al-Amin ◽  
Hong Wang
Keyword(s):  
Acceptable Level ◽  
Lower Probability ◽  
Location Factor ◽  
Site Specific ◽  
Location Class ◽  
Standard Design ◽  
Operating Stress ◽  
Design Requirements ◽  
New Location ◽  
Level Of Risk

In Canada, when location class changes on a gas pipeline CSA Z662-15 requires operators to comply with design requirements of the new location class or perform an Engineering Assessment (EA). The compliance option is often perceived by regulators and the public as the better option compared to the EA option. This paper demonstrates that a well-executed EA that accounts for relevant threats and consequences, and provides explicit levels of reliability, can deliver improved pipeline safety. To comply with design requirements with respect to location factor, the two compliance options are to de-rate or replace the pipeline to achieve the lower operating stress level dictated by the new location factor. However, lower operating stress levels do not always address the higher risk levels or safety concerns caused by the change in class and ensuing potential increase in mechanical damage. For gas pipelines, where class location is applicable, ensuring human safety is the primary objective of pipeline integrity management. In this context, safety is defined as the control of recognized hazards to achieve an acceptable level of risk. To provide site-specific safety, an acceptable level of risk needs to be achieved by ensuring sufficiently low enough probabilities of failure for given site-specific consequence levels. Increased wall thickness via pipe replacement, can lead to lower probability of failure for a pipeline. However, as pipelines are subjected to many different combinations of threats, which depend on site specific conditions, the pipelines that are designed with thicker walled pipes for higher location classes do not always provide lower probabilities of failure. As the general design considerations do not account for the site specific threats and mitigation actions, complying with design requirements alone do not consistently provide lower probabilities of failure, especially in areas of potentially higher third-party activities. In TransCanada’s site-specific EAs, quantitative risk or reliability assessments consider verified population estimates, actual lethality zones and site-specific threats. Appropriate and site-specific mitigation actions address the actual risk. This enables providing an appropriate site specific reliability level. Case studies and comparison between methodologies are used to illustrate the importance of performing site-specific EAs using site-specific information to achieve safety levels that are greater than those achieved by strictly complying with the standard design requirements. Accounting for actual-site specific threats and the actual consequences ensures accurate assessment of risk and consequent appropriate mitigation and efficient risk reduction.

An Engineering Assessment to Evaluate Integrity Options for Out of Class Pipelines

2014 ◽  
Author(s):  
Hong Wang ◽  
Shahani Kariyawasam ◽  
Pauline Kwong
Keyword(s):  
Urban Areas ◽  
Operating Pressure ◽  
Pressure Reduction ◽  
Safety Level ◽  
Location Factor ◽  
Site Specific ◽  
Testing Procedures ◽  
Location Class ◽  
Regulatory Constraints ◽  
Pipe Replacement

As population growth and development occurs along the pipeline right of way, the class location of pipeline segments could change to a higher class designation. A higher location class designation has a more stringent location factor according to Canadian Standard Association (CSA) Z662-11 Clause 4.3.7. For this situation, Onshore Pipeline Regulations (OPR) s.42 requires pipeline operators to submit a proposed plan in conformance with CSA Z662 requirements in Clause 10.7. Typically for compliance, a change to higher class designation leads to pipe replacement or operating pressure reduction (compliance options). Alternatively, the pipeline segment could also be subjected to an engineering assessment (EA) to develop other measures which are as safe as or safer than the compliance options. The CSA code requirements of pipeline replacement or pressure reduction for out-of-class pipe cater to generic cases, and essentially make the out-of-class pipe segment comply such that it is within class. In contrast, a site-specific EA considers the actual pipe conditions, the relevant hazards, and the case specific solutions. Therefore, the site-specific EA provides a more appropriate solution for the problem at hand and ensures a risk consistent approach for the class change site. This also provides a safety level that is equivalent or above the regulatory requirements. A three-level engineering assessment methodology was developed for an out-of-class EA. In the first level assessment, the design, construction, testing procedures and the location class development are reviewed to understand the regulatory constraints and compliance aspects. In the second level assessment, all the potential hazards are identified and assessed to determine the pipeline condition. Finally, in the third level assessment, quantitative reliability assessment techniques were utilized to determine the optimized mitigation activities that can make the pipe segments as safe as or safer than the compliant options. The class change EA used the above methodology to quantitatively compare mitigation activities with pipe replacement and reduced operating pressure scenarios. Some mitigation activities provided greater safety than pipe replacement and reduced operating pressure scenarios, thus providing safer options while avoiding pipeline service interruption; minimizing in-field disturbances and related risks of replacement; and providing cost-benefit optimization. The growth of urban areas and related encroachment on pipeline corridors is a common occurrence. Therefore this EA approach has industry wide applications in providing safer and more optimized solutions.

DIGITAL ECONOMY AS A BASIS OF ECONOMIC SECURITY OF THE COUNTRY

2021 ◽  
pp. 70-72
Author(s):  
М.В. Свирина
Keyword(s):  
Economic Development ◽  
Economic Security ◽  
Digital Economy ◽  
Security System ◽  
Acceptable Level ◽  
Complete Elimination ◽  
Level Of Risk

В данной статье рассматриваются особенности функционирования цифровой экономики в современных условиях. В условиях цифровой экономики полное устранение опасности или риска неизбежно влечет за собой отказ от дополнительных возможностей развития экономики. Поэтому при построении системы безопасности необходимо определить приемлемый уровень риска как с точки зрения его управляемости и предсказуемости, так и возможных последствий. This article discusses the features of the functioning of the digital economy in modern conditions. In the digital economy, the complete elimination of danger or risk inevitably entails the rejection of additional opportunities for economic development. Therefore, when building a security system, it is necessary to determine an acceptable level of risk, both in terms of its controllability and predictability, as well as possible consequences.

scholarly journals Visual drainage assessment: A standardised visual soil assessment method for use in land drainage design in Ireland

2016 ◽  
Vol 55 (1) ◽  
pp. 24-35 ◽  
Author(s):  
P. Tuohy ◽  
J. Humphreys ◽  
N.M. Holden ◽  
J. O’Loughlin ◽  
B. Reidy ◽  
...  
Keyword(s):  
Water Table ◽  
Discharge Capacity ◽  
Drainage System ◽  
Assessment Method ◽  
Site Specific ◽  
Soil Assessment ◽  
Land Drainage ◽  
Standard Design ◽  
Rainfall Recharge ◽  
A Site

AbstractThe implementation of site-specific land drainage system designs is usually disregarded by landowners in favour of locally established ‘standard practice’ land drainage designs. This is due to a number of factors such as a limited understanding of soil–water interactions, lack of facilities for the measurement of soil’s physical or hydrological parameters and perceived time wastage and high costs. Hence there is a need for a site-specific drainage system design methodology that does not rely on inaccessible, time-consuming and/or expensive measurements of soil physical or hydrological properties. This requires a standardised process for deciphering the drainage characteristics of a given soil in the field. As an initial step, a new visual soil assessment method, referred to as visual drainage assessment (VDA), is presented whereby an approximation of the permeability of specific soil horizons is made using seven indicators (water seepage, pan layers, texture, porosity, consistence, stone content and root development) to provide a basis for the design of a site-specific drainage system. Across six poorly drained sites (1.3 ha to 2.6 ha in size) in south-west Ireland a VDA-based design was compared with (i) an ideal design (utilising soil physical measurements to elucidate soil hydraulic parameters) and (ii) a standard design (0.8 m deep drains at a 15 m spacing) by model estimate of water table control and rainfall recharge/drain discharge capacity. The VDA method, unlike standard design equivalents, provided a good approximation of an ideal (from measured hydrological properties) design and prescribed an equivalent land drainage system in the field. Mean modelled rainfall recharge/drain discharge capacity for the VDA (13.3 mm/day) and ideal (12.0 mm/day) designs were significantly higher (P< 0.001, s.e. 1.42 mm/day) than for the standard designs (0.5 mm/day), when assuming a design minimum water table depth of 0.45 m.

Overview of Seismic Issues in Design Certification and Combined License Application Reviews

2009 ◽  
Author(s):  
Jim Xu ◽  
Sujit Samaddar
Keyword(s):  
Seismic Design ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Response Spectra ◽  
Nuclear Regulatory Commission ◽  
Lessons Learned ◽  
Site Specific ◽  
License Application ◽  
Standard Design

The U.S. Nuclear Regulatory Commission (NRC) established a new process for licensing nuclear power plants under Title 10 of the Code of Federal Regulations (10 CFR) Part 52, “Licenses, Certifications, and Approvals for Nuclear Power Plants,” which provides requirements for early site permits (ESPs), standard design certifications (DCs), and combined license (COL) applications. In this process, an application for a COL may incorporate by reference a DC, an ESP, both, or neither. This approach allows for early resolution of safety and environmental issues. The COL review will not reconsider the safety issues resolved by the DC and ESP processes. However, a COL application that incorporates a DC by reference needs to demonstrate that pertinent site-specific parameters are confined within the safety envelopes established by the DC. This paper provides an overview of site parameters related to seismic designs and associated seismic issues encountered in DC and COL application reviews using the 10 CFR Part 52 process. Since DCs treat the seismic design and analysis of nuclear power plant (NPP) structures, systems, and components (SSC) as bounding to future potential sites, the design ground motions and associated site parameters are often conservatively specified, representing envelopes of site-specific seismic hazards and parameters. For a COL applicant to incorporate a DC by reference, it needs to demonstrate that the site-specific hazard in terms of ground motion response spectra (GMRS) is enveloped by the certified design response spectra of the DC. It also needs to demonstrate that the site-specific seismic parameters, such as foundation-bearing capacities, soil profiles, and the like, are confined within the site parameter envelopes established by the DC. For the noncertified portion of the plant SSCs, the COL applicant should perform the seismic design and analysis with respect to the site-specific GMRS and associated site parameters. This paper discusses the seismic issues encountered in the safety reviews of DC and COL applications. Practical issues dealing with comparing site-specific features to the standard designs and lessons learned are also discussed.

Determining an acceptable level of risk

1988 ◽  
Vol 22 (8) ◽  
pp. 873-876 ◽  
Author(s):  
Curtis C. Travis ◽  
Holly A. Hattemer-Frey
Keyword(s):  
Acceptable Level ◽  
Level Of Risk

scholarly journals The Use of Predictive Maintenance in the Production Processes

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Aneta NAPIERAJ
Keyword(s):  
Data Analysis ◽  
Production Process ◽  
Preventive Maintenance ◽  
Cost Reduction ◽  
Predictive Maintenance ◽  
Acceptable Level ◽  
Safety Requirements ◽  
Production Processes ◽  
Machine Reliability ◽  
Level Of Risk

Failures are a problem for every company that causes the plant to stop working and thus incur losses. It is therefore obvious thatcompanies want to eliminate unplanned downtime in the production process. In the wake of the still increasing demands in termsof productivity and safety requirements, cost reduction, the industry is forced to seek the optimum between economic requirementsand an acceptable level of risk in terms of security. Modern factories equipped with computerized processes and extensive diagnostictools often do not use all the information that is collected from the hardware level. It happens that some of the relationshipsbetween events are often overlooked or neglected.The article presents an approach to increasing machine reliability through predictive data analysis. The assumptions of the predictiveand preventive maintenance methods are presented. The threats and possibilities offered by this methodology implemented inthe production process are presented.

scholarly journals Cluster analysis and individual anthropogenic risk

2021 ◽  
Author(s):  
V.V. Moskvichev ◽  
U.S. Postnikova ◽  
O.V. Taseiko
Keyword(s):  
Cluster Analysis ◽  
Population Density ◽  
Risk Analysis ◽  
Assessment Methods ◽  
Acceptable Level ◽  
Mathematical Approach ◽  
Multivariate Statistic ◽  
General Basis ◽  
Territorial Group ◽  
Level Of Risk

Models and assessment methods of anthropogenic risk are analyzed at this article, general basis of mathematical approach for risk analysis is disclosed. Based on multivariate statistic methods, algorithm of analysis for Siberian territories safety is formulated, it allows to define acceptable level of risk for each territorial group (cities with population density more than 70 000, towns with population less than 70 000, and municipals areas).

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