Design Certification Research Articles

Urban Sustainability: Network Dependency Across the Urban Rural Divide in Canada’s Built Environment

Urban sustainability and sustainable development have permeated both public and academic discourse since the 1980s Brundtland Commission Report. The report defined sustainability and situated it within social, economic, and environmental factors emphasizing sustainable development as a path forward. Academics, scientists, and policy makers undertook the task over the subsequent decades to define sustainability, operationalize it, measure it, and monitor it. However, despite the rapid progress and leaps in understanding the discourse has its weaknesses, its singular focus on particular elements of sustainability systems, its lack of cross level examination across scalar divides, its primarily urban focus, and its majority functionalist approach. These weaknesses leave a void in the understanding of urban sustainability as an element of an economic, social, and environmental interconnected urban-rural system. A subfield is emerging to understand this interconnectedness of sustainability through examining the built environment and the urban-rural divide. However, currently, Canada is largely absent from this subfield’s exploration. In order to expand this exploration and analyze the sustainability interconnections within Canada through the urban built environment, the Leadership in Energy and Environmental Design (LEED) certification will be a key element going forward, because LEED is a globally accepted green building certification system that is primarily utilized in North America. This research thesis contributes, as a substantive text, to this subfield through answering the main question left open by current discourses: Are there any discrepancies between the projected sustainability of LEED projects and the actual sustainability realities of the projects? With further queries being posited: What is the sustainability reality of the LEED buildings; what are the sustainability realities of the users/tenants within the LEED buildings; and, what is the sustainability reality of the LEED buildings across the urban-rural divide? I garnered the answers through a mixed quantitative/qualitative analysis of case studies within the Canadian urban built environment: LEED projects. The projects will be examined utilizing an urban metabolic analysis of the quantitative data and a point-based scoring system adapted from a Strengths, Weaknesses, Opportunities, and Threats analysis (SWOT) I named Focus Factor Analysis to quantify qualitative elements of the projects. Consequently, the analysis will also highlight connections between the urban area projects and the rural surroundings using a combination of databases and LEED, corporate, and government reports. Discrepancies have been found and although the LEED projects are sustainable on the local level on a network level they are not.

Quality Concerns in Nursing Homes That Serve Large Proportions of Residents With Serious Mental Illness.

Nursing homes (NHs) are serving greater proportions of residents with serious mental illness (SMI), and it is unclear whether this affects NH quality. We analyze the highest and lowest quartiles of NHs based on the proportion of residents with SMI and compare these NHs on facility characteristics, staffing, and quality stars. National Certification and Survey Provider Enhanced Reports data were merged with NH Compare data for all freestanding certified NHs in the continental United States in 2016 (N = 14,460). NHs were categorized into "low-SMI" and "high-SMI" facilities using the lowest and highest quartiles, respectively, of the proportion of residents in the NH with SMI. Bivariate analyses and logistic models were used to examine differences in organizational structure, payer mix, resident characteristics, and staffing levels associated with high-SMI NHs. Linear models examined differences in quality stars. High-SMI facilities were found to report lower direct-care staffing hours, have a greater Medicaid-paying resident census, were more likely to be for-profit, and scored lower on all NH Compare star ratings in comparison to all other NHs. As the SMI population in NHs continues to grow, a large number of residents have concentrated in a few NHs. These are uniquely different from typical NHs in terms of facility characteristics, staffing, and care practices. While further research is needed to understand the implications of these trends, public policymakers and NH providers need to be aware of this population's unique-and potentially unmet-needs.

Safety analysis of an advanced passively-cooled small modular reactor during station blackout scenarios and normal operation with RELAP5/SCDAP

NuScale reactor design utilizes natural circulation for heat removal in the primary system, and it is maximized the usage of passive safety systems. Elimination of pumps from the primary system leads to specific phenomenology in this reactor. In this research, NuScale design is selected as a reference case study based on its design certification application (DCA). The main objective of this study is to evaluate the capability of the reactor to withstand against station blackout and to represent phenomenology involved in this specific integral PWR design. In this research, RELAP5/SCDAP is used to model the thermal-hydraulics performance of the reactor during steady-state and station blackout conditions. Furthermore, a new loading pattern is proposed for the reactor core, and its neutronic parameters are calculated using MCNP5, and three-dimensional visualization of the neutron flux in the core is depicted. Critical heat fluxes along the reactor core height are calculated based on Groenveld look-up table and Bowring correlation in the steady-state operation. Also, minimum departure from nucleate boiling ratio is computed for the proposed core based on hot rod heat flux. The results of this research are validated based on design certification application data. Then, the reactor behavior during two station blackout scenarios is getting focused. In the first scenario, no additional failure is assumed, while in the second scenario, failure of the emergency core cooling system is taken into account, and the performance of the reactor is studied for three days after the initiation of these accidents. The dominant phenomenon in each phase of these accidents has been analyzed. Results show significant improvements in decay heat removal in comparison with typical current PWRs during the station blackout accident. However, in some stages of accidents, remarkable fluctuations in the fluid flow of the primary system have been observed. In the case of long term exposure of the reactor to these flow oscillations, it may lead to structural damages and its further consequences.

The Impact of Indoor Environmental Quality of Green Buildings on Occupants' Health and Satisfaction: A systematic review

Introduction: The main benefits of green buildings for energy and water conservation have been investigated and well recognized in previous studies. However, indoor environmental quality (IEQ) and human health benefits of green buildings have not been examined comprehensively. This study aimed to conduct a systematic review over the current status of green and non- green buildings on their occupants’ health and satisfaction. Method: A systematic search was conducted throughout the following databases: Science Direct, Google Scholar, and Springer. We reviewed 690 articles that examined the relationship between buildings and health. In total, after excluding the irrelevant titles and non-­English articles, 40 papers were included in the final analysis. Articles that evaluated IEQ factors and occupants’ health through surveys from 2005 to 2018 years were selected for investigation. Results: The most important result of this study was identification of important factors in IEQ, including building design, aesthetics, and ergonomics, which have been less evaluated in previous research. Contrary to our assumption, the results of several studies indicated a further decline in IEQ parameters in buildings with Leadership in Energy and Environmental Design (LEED, USA) and Building Research Establishment Environmental Assessment Method (BREEAM, Europe) certification. However, performance improvements were reported in green buildings located in Asia (especially Singapore and Taiwan). Conclusion: According to this systematic review, we cannot claim that occupants of the green buildings enjoy higher IEQ, satisfaction, or health, compared with the occupants of non-green buildings.

Understanding the Effects of Capturing Climate and Occupancy Trends During Concept-Stage Sustainable Building Design

Abstract This paper presents a model prediction to capture specifically how energy usage in sustainable buildings on college campuses is affected by different variables of student life. The California State University, Fullerton (CSUF) Student Housing Phase III, which received a Platinum Leadership in Energy and Environmental Design (LEED) certification for the Building Design and Construction category, with its performance in a LEED California Nonresidential Title 24 (NRT24) and ASHRAE 90.1 climate zones, is used as a case study to illustrate the method. Through LEED-approved software, the standard compliant energy models are compared with the occupancy-scheduled models along with the actual energy consumption in different climate zones. The results provide insight into how variables within student dormitory life affect the total building energy usage. The total amount of energy consumed per area is one new factor providing understanding into occupancy trends. This new data set reveals more understanding regarding how and where the energy is consumed to maintain a comfortable learning environment. The LEED certification program is one benchmark used to determine sustainable building design. Designers must adhere to set standards before being awarded a U.S. Green Building Council (USGBC) certification such as LEED. The results from this paper will provide input over which variables within student dormitory life affect the energy usage of the building. With the model results, some solutions are presented to update the LEED project certification as well as to reduce student energy usage.

Heterogeneous Iris One-to-One Certification with Universal Sensors based On Quality Fuzzy Inference and Multi-Feature Fusion Lightweight Neural Network.

Due to the unsteady morphology of heterogeneous irises generated by a variety of different devices and environments, the traditional processing methods of statistical learning or cognitive learning for a single iris source are not effective. Traditional iris recognition divides the whole process into several statistically guided steps, which cannot solve the problem of correlation between various links. The existing iris data set size and situational classification constraints make it difficult to meet the requirements of learning methods under a single deep learning framework. Therefore, aiming at a one-to-one iris certification scenario, this paper proposes a heterogeneous iris one-to-one certification method with universal sensors based on quality fuzzy inference and a multi-feature entropy fusion lightweight neural network. The method is divided into an evaluation module and a certification module. The evaluation module can be used by different devices to design a quality fuzzy concept inference system and an iris quality knowledge concept construction mechanism, transform human logical cognition concepts into digital concepts, and select appropriate concepts to determine iris quality according to different iris quality requirements and get a recognizable iris. The certification module is a lightweight neural network based on statistical learning ideas and a multi-source feature fusion mechanism. The information entropy of the iris feature label was used to set the iris entropy feature category label and design certification module functions according to the category label to obtain the certification module result. As the requirements for the number and quality of irises changes, the category labels in the certification module function were dynamically adjusted using a feedback learning mechanism. This paper uses iris data collected from three different sensors in the JLU (Jilin University) iris library. The experimental results prove that for the lightweight multi-state irises, the abovementioned problems are ameliorated to a certain extent by this method.

Critical Heat Flux Model for Vertical Annular Mist Flow Conditions in a Rod Bundle

As part of its design certification effort, NuScale Power has completed a series of low mass flux [<1000 kg/(m2‧s)] critical heat flux (CHF) tests for a wide range of pressures at Stern Laboratories in Canada. Earlier studies have demonstrated that under annular flow conditions, disturbance waves with circulating vortices traverse the rod surface. The disturbance wave slides over and significantly influences energy transport in the co-current vapor-liquid sublayer at the heater interface. This paper describes the mechanisms leading to the onset of CHF in a vertical rod bundle experiencing annular mist flow conditions. The paper presents a new CHF model that implements a local disturbance wave velocity. A comparison of the model to the U1 CHF data set from Stern Laboratories shows excellent agreement over the full range of annular mist flows, pressures, and subcooled conditions for the specific spacer grids implemented in the study.

Multibody modeling for concept-level floating offshore wind turbine design

Existing Floating Offshore Wind Turbine (FOWT) platforms are usually designed using static or rigid-body models for the concept stage and, subsequently, sophisticated integrated aero-hydro-servo-elastic models, applicable for design certification. For the new technology of FOWTs, a comprehensive understanding of the system dynamics at the concept phase is crucial to save costs in later design phases. This requires low- and medium-fidelity models. The proposed modeling approach aims at representing no more than the relevant physical effects for the system dynamics. It consists, in its core, of a flexible multibody system. The applied Newton–Euler algorithm is independent of the multibody layout and avoids constraint equations. From the nonlinear model a linearized counterpart is derived. First, to be used for controller design and second, for an efficient calculation of the response to stochastic load spectra in the frequency-domain. From these spectra the fatigue damage is calculated with Dirlik’s method and short-term extremes by assuming a normal distribution of the response. The set of degrees of freedom is reduced, with a response calculated only in the two-dimensional plane, in which the aligned wind and wave forces act. The aerodynamic model is a quasistatic actuator disk model. The hydrodynamic model includes a simplified radiation model, based on potential flow-derived added mass coefficients and nodal viscous drag coefficients with an approximate representation of the second-order slow-drift forces. The verification through a comparison of the nonlinear and the linearized model against a higher-fidelity model and experiments shows that even with the simplifications, the system response magnitude at the system eigenfrequencies and the forced response magnitude to wind and wave forces can be well predicted. One-hour simulations complete in about 25 seconds and even less in the case of the frequency-domain model. Hence, large sensitivity studies and even multidisciplinary optimizations for systems engineering approaches are possible.

The Influence of Low-Temperature Restorative Heat Treatment on the Structure and Mechanical Properties of Boiler Drum Metal after Long-Term Operation

The drum metal properties of the BKZ-160-100FB and TP-85 boilers installed at the Irkutsk TETs-11 combined heat and power plant were investigated after these boilers had been in operation for 259 000 and 224 000 h, respectively, and after they had been subjected to low-temperature restorative heat treatment, which was carried out with steam produced by an external boiler after replacing all unions installed in the drum’s water volumes. “Plugs” made of grade 22K carbon steel and of grade 16GNM low-alloy steel cut from the drum shell rings were used as research subjects. The samples were subjected to metallographic analysis, tensile tests, impact bending test, and hardness measurement test. The results of tensile tests carried out at room temperature and at the metal operation temperature are presented. The results of drum metal U-notched specimens impact strength tests obtained at room temperature are given. Impact strength tests on V-notched specimens were carried out for samples after their metal had been subjected to low-temperature restorative heat treatment in the temperature range from –10 to +80°C. Based on the results of the V-notched specimens tests, the ductile constituent in the fractures was determined, and the drum metal ductile-to-brittle transition temperature was determined. The microstructure and mechanical properties that the drum metal had after having been in operation and having passed subsequent low-temperature restorative heat treatment were in compliance with the requirements of the relevant regulatory documents. After the boiler drum metal had been subjected to low-temperature restorative heat treatment, the studied steel samples showed a higher proof strength both at room temperature and at the operation temperature. Based on the data obtained from the investigations of boiler drum metal after it had been in operation and then subjected to low-temperature restorative heat treatment, technical diagnostics, and numerical strength analysis, it was recommended to extend the service life of the drums at their design (certificate) parameters.

The effect of green practices on emotional attachment and green loyalty of coffee shop consumers (Turkey)

As individuals have recently become more sensitive towards environmental issues, green marketing has emerged as an important strategic tool in order to gain competitive advantage for hospitality and food and beverage enterprises. This study is aimed at determining the effect of green marketing practices on coffee shop customers' loyalty and emotional attachment. For this aim, the customers of 3 Starbucks (coffee shop) operating in Mugla province (Turkey) and having Leadership in Energy and Environmental Design (LEED) Certificate (n=404) were included in the scope of this study. The hypotheses determined for this aim were tested via path analysis with latent variables which was one of the structural equation modellings. According to test results, it was concluded that green practices had a positive significant effect on attachment to green businesses; customer attachment to green businesses had a positive significant effect on green loyalty to both green businesses and green products and also loyalty towards green businesses had a negative impact on loyalty towards green products. These results show that it is important for food and beverage businesses to adopt green practices both for raising awareness towards environmental protection and also for creating customer loyalty and emotional attachment. In this way, environmentally friendly practices provide competitive advantage as well as an increase in the number of environmentally friendly customers for businesses.

A Novel Semantic Cohesion Approach for Chinese Airworthiness Regulations: Theory and Application

Airworthiness regulation documents are critical, which contain massive safe constraints for system design and airworthiness certification. The textual information of airworthiness regulations is organized and stored in a hierarchical and scattered form due to the unique provision structure. The linguistic form of legal provision brings the problems of incompleteness semantic information and syntactic structure to each legal clause, which limits the application of Natural Language Processing (NLP) technology in the field of airworthiness safety. In this article, a novel theory of semantic cohesion is proposed for Chinese airworthiness regulations, in which four critical elements are contained, including definition, model, theorem and rules. The definition of attributive directed graph model is proposed to achieve the graphical representation of airworthiness regulation texts. Moreover, the graphical issue of regulation texts is proved in accordance with the characteristic of hierarchical provision structure based on graph theory, and the rules of edge structure construction are provided. Based on the theory, a new node content link algorithm is proposed to achieve the tasks of semantic cohesion and structure conversion for Chinese airworthiness regulation texts. According to the hierarchical structure characteristic of regulation texts, the algorithm can convert the provision structure to the general narrative linguistic form by constructing edges with semantic cohesion relation. As a result, provision sentences with complete semantic information and syntactic structure can be generated. The algorithm has been deployed on the current 119 airworthiness regulation texts to verify the validity and feasibility. The experimental results show that the algorithm achieves efficient performance in the tasks of structure conversion and semantic cohesion, and the algorithm performs reliably with an accuracy rate of 100%. The problem of application limitation for NLP technology to Chinese airworthiness regulation texts has been resolved, which promotes the intelligent and automatic development of airworthiness safety.

Urban Built-Up and Leader in Energy and Environmental Design (LEED) Certification: A Case Study of National Capital Territory (NCT) of Delhi, India

Urban Built-Up and Leader in Energy and Environmental Design (LEED) Certification: A Case Study of National Capital Territory (NCT) of Delhi, India

Federal policy, local policy, and green building certifications in the U.S.

Buildings account for about 40% of total U.S. energy consumption and around a third of total energy-related CO2 emissions. Concerns about these emissions have led federal, state, and local governments to pass policies to reduce energy use in buildings. In this paper, we examine whether policies aimed at encouraging green building certifications are associated with an increase in the gross floor area per capita of Leadership in Energy and Environmental Design (LEED) certifications. We focus specifically on commercial LEED building retrofits certified under - :existing buildings: operations and maintenance (EB), commercial interiors (CI), and core and shell (CS) rating system categories. Using a panel data approach, we find that metropolitan statistical areas (MSAs) with local policies, particularly requirement and density programs, are associated with significant increases in commercial LEED retrofits. Specifically, we find that the switch of an MSA from having no requirement policy to having a requirement policy is associated with an increase of 0.22 LEED sqft/capita [0.02 LEED sqm/capita] (compared to an average of 0.6 LEED sqft/capita [0.06sqm/capita] across all buildings in 2016). We also find that federal policies and improvements to the LEED rating system are associated with increases in LEED certifications. While the impacts of federal policy and LEED rating system updates are difficult to separate, our work suggests that local policy, federal policy, and modifications to the LEED rating system can work in concert to drive green building adoption.

Evaluating Improvements and Shortcomings in Clinician Satisfaction With Electronic Health Record Usability

With the widespread adoption of electronic health records (EHRs), there is increased focus on addressing the challenges of EHR usability, ie, the extent to which the technology enables users to achieve their goals effectively, efficiently, and satisfactorily.1 Poor usability is associated with clinician job dissatisfaction and burnout and could have patient safety consequences.2,3,4 The US Department of Health and Human Services Office of the National Coordinator for Health Information Technology established safety-enhanced design certification requirements for EHRs to promote usability. These requirements stipulate that vendors must conduct and report results of formal usability testing, including measuring satisfaction with the EHR system.5 Results are publicly available. While some vendors use a 5-point, ease-of-use rating scale, most vendors use the system usability scale (SUS), which is a validated posttest questionnaire that measures user satisfaction with product usability.6 The questionnaire provides a score (range, 0-100) based on a participant’s rating of 10 statements regarding a product’s usability.6 Higher scores indicate greater satisfaction with usability.6 Based on an analysis of more than 200 studies of various products in various industries, an SUS score of 68 is considered the average benchmark, and an SUS of 80 is considered the above-average benchmark.6 Recognizing the importance of satisfaction with EHR usability to clinician burnout and patient safety, reported product 2015 SUS scores for EHR systems were compared with 2014 SUS scores and with benchmarks to evaluate whether satisfaction is improving.2,3,4

Human-centered Approach for Proper Functioning of LEED Criteria; A Case Study in Tehran

Buildings are rated in five main categories according to the LEED standard to receive an environment-friendly design certificate. Sustainability, water efficiency, material properties, energy consumption, and the quality of indoor spaces are main criteria which confirm the proper function of a building in terms of optimal energy consumption. However, the role of residents and behavioral aspects in the consumption of energy and the decent application of energy standards are neglected. It is beyond doubt that the residents’ behavior is one of the most important factors in performance-based building design. Moreover, the individual mistakes, which most of the times cause energy dissipation, cannot be ignored. This research proposes "Integrated Interactive System" as a human-centered approach with the aim of minimizing energy consumption. A survey is conducted, and this system is evaluated as a case study in Tehran.

Environmental and sustainable aspects of green building: A review

Public and scientific focus of interest on climate changes, population increase, rapid urbanization is rising day by day. Thus, increased demand for green buildings that reduces negative impacts, and can creates positive impacts on climate, natural environment and sustainable development is a new topic. Green buildings must be not only eco-friendly (efficiently use energy, water, and other resources, use renewable energy, reduce pollution and waste, enable reuse and recycling, have good indoor environmental quality, use of materials that are non-toxic, ethical and sustainable) but also function as the key part to provide a comfortable working/living environment for human activities and improve quality of life. It is realised that green buildings as a worldwide response to raise awareness of the role of human activity in global climate changes, with maximum expression in Leadership in Energy and Environmental Design (LEED) Certification and its five basic requirements: Sustainable Space (SS), Materials and Resources (MR), Energy and Atmosphere (EA), Environmental Quality (EQ), and Water Efficiency (WE).The aim of this study is to review the environmental and sustainable aspects of green buildings. For this goal, environmental and sustainable aspects of green building including its origin, concept, eco-friendly properties, benefits, tools, rating systems, certifications are given and discussed in detail in this study.

Small Modular Reactor Control Room Workstation Demonstration

A control room simulator was designed to model the operation of a NuScale small modular reactor (SMR) nuclear power plant and provide enough fidelity to perform staffing validation studies for Nuscale’s Nuclear Regulatory Commission Design Certification Application. The simulator serves as a simulated control room with work stations to mimic the operation of an SMR module, turbine generator, and support systems using a proprietary human system interface (HSI) software package. The simulator, which includes all HSI screens, was designed by a team of Human Factors and Plant Operations staff to capitalize on best practices, lessons learned, and operating experience using the Agile development process. Finally, the design process included the development of plant operating procedures and training material as well as a training platform for future plant operators at an SMR nuclear power plant.

“Alternative” materials in the green building and construction sector

Purpose The construction, use and demolition of buildings carry enormous environmental burdens. As one step to reduce a building’s environmental impact, green building design guidelines and certification programs, such as Leadership in Energy and Environmental Design, Cradle to Cradle and the Whole Building Design Guide, promote the specification of alternative, non-traditional building materials. Alternative materials carry a variety of potential benefits: reducing the amount of energy and other resources needed to create building materials; creating healthier indoor and outdoor environments; diverting or reducing waste from landfills; reducing the use of scarce, critical or economically volatile materials; and spurring innovation in the building industry. However, a lack of clarity surrounds alternative materials and creates a barrier to their usage. The purpose of this paper is to review definitions of alternative materials in various design guidelines in order to provide context to their specification and usage. Design/methodology/approach Through a survey of green building programs and guidelines, existing literature on alternative materials, and life-cycle assessment using multiple inventory databases, this study tackles the following questions: what constitutes an alternative building material; what are the current barriers to their specification; how are they specified in the most common design guidelines; and do alternative building materials present a “greener” alternative? Findings These results show that while often alternative materials do in fact show promise for reducing environmental impacts of the built environment, by how much can be a challenging question to quantify and depends on a variety of factors. While many green building guides and certification systems provide recommendations for use of alternative materials, the sheer diversity and uncertainty of these systems coupled with the complexity in understanding their impacts still present a significant barrier to their specification. Much work remains in a variety of disciplines to tackle these barriers. A clear emphasis should be on better understanding their environmental impacts, particularly with respect to the context within the built environment that their specification will provide energy, resource and emission savings. Other key areas of significant work include reducing costs, removing regulatory and code barriers, and educating designers, consumers, and end-users. Originality/value Alternative materials are defined and specified in a diversity of contexts leaving the design and construction communities hesitant to promote their use; other work has found this to be a key barrier to their widespread usage. By compiling definitions, barriers and design guidelines instructions while also exploring analytically the benefits of specific cases, this work provides a foundation for better understanding where new, more sustainable materials can be successfully specified.

Added value? Denaturalizing the “good” of urban greening

AbstractIn recent years, “urban greening” has become a new keyword in urban policy and practice, used to describe a proliferation of urban quality of life and environmental sustainability initiatives including street trees, public parks, greenways, farmers' markets, green roofs, and LEED certification in design. The emerging critical literature on urban greening has highlighted important ways green's social and economic added value affects the political economy of contemporary greening and produces inequalities in access to real or perceived environmental goods. However, such research has only infrequently asked why and under what conditions naturalized understandings of green as “good” make it possible for such initiatives to add value in the first place. As a result, it offers only partial explanations of why green has the effects it has—for instance, increasing property values—and only very rarely questions the fundamental “good” of nature itself. I argue that integrating insights on green's naturalized social and economic value from a growing body of social‐theoretical work across geography and the social sciences can complement political economic explanations for greening and provide new vantage points for critique.

Design-airworthiness integration method for general aviation aircraft during early development stage

PurposeMajor changes of an aircraft configuration are conducted during the early design stage. It is important to include the airworthiness regulations at this stage while there is extensive freedom for designing. The purpose of this paper is to introduce an efficient design framework that integrates airworthiness guidelines and documentation at the early design stage.Design/methodology/approachA new design and optimization process is proposed that logically includes the airworthiness regulations as design parameters and constraints by constructing a certification database. The design framework comprises requirements analysis, preliminary sizing, conceptual design synthesis and loads analysis. A design certification relation table (DCRT) describes the legal regulations in terms of parameters and values suitable for use in design optimization.FindingsThe developed framework has been validated and demonstrated for the design of a Federal Aviation Regulations (FAR) 23 four-seater small aircraft. The validation results show an acceptable level of accuracy to be applied during the early design stage. The total mass minimization problem has been successfully solved while satisfying all the design requirements and certification constraints specified in the DCRT. Moreover, successful compliance with FAR 23 subpart C is demonstrated. The proposed method is a useful tool for design optimization and compliance verifications during the early stages of aircraft development.Practical implicationsThe new certification database proposed in this research makes it simpler for engineers to access a large amount of legal documentation related to airworthiness regulations and provides a link between the regulation text and actual design parameters and their bounds.Originality/valueThe proposed design optimization framework integrates the certification database that is built of several types of legal documents such as regulations, advisory circulars and standards. The Engineering Requirements and Guide summarizes all the documents and design requirements into a single document. The DCRT is created as a summary table that indicates the design parameters affected by a given regulation(s), the design stage at which the parameter can be evaluated and its value bounds. The introduction of the certification database into the design optimization framework significantly reduces the engineer’s load related for airworthiness regulations.