Interruption Duration Research Articles

An Analysis of the Operation of Distribution Networks Using Kernel Density Estimators

Efficiency in the operation of distribution networks is one of the commonly recognised goals of the Smart Grid aspect. Novel approaches are needed to assess the level of energy loss and reliability in electricity distribution. Transmission of electricity in the power system is invariably accompanied by certain physical phenomena and random events causing losses. Identifying areas where excessive energy losses or excessive grid failure occur is a key element for energy companies in resource management. The study presented in the article is based on data obtained from distribution system operators concerning 41 distribution regions in Poland for a period of 5 years. The first part of the article presents an analysis of the distribution of values for the introduced energy density and energy losses in the lines of medium- and low-voltage networks and in transformers supplying the low-voltage network. The second part of the article presents the assessment of the network reliability of the same distribution regions based on analysis of the distributions of System Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Index (SAIFI) values for planned and unplanned outages. Data analysis is performed by non-parametric methods by means of kernel estimators.

Power Outage Sensing Device based on IOT for Service Quality Evaluation in the PLN Distribution System

In overcoming electrical disturbances, PLN implements an equipment protection system that aims to reduce the areas experiencing power outage. However, this protection system has not been integrated with the SCADA system. As a parameter to maintain customer service continuity, PLN uses customer-based indexes, i.e., the Customer Average Interruption Duration Index (CAIDI) and Customer Average Interruption Frequency Index (CAIFI). In the calculation of those index values, the record of power outage occurrence at PLN is still not accurate because the duration and frequency of power outage based on customer complaints. In this study, a Power Outage Sensing device is installed on the secondary distribution system transformer 380/220 which can ensure the location, record the frequency and duration of power outage and serve customers in real time based on IOT using WEMOS D1 and optocoupler sensors which can then be accessed on a web. In its implementation, all power outage is recorded in the database and can be accessed on the web interface. This device can speed up the recovery of disturbances in the system after an outage and perform accurate CAIDI and CAIFI index calculations as customer service evaluations.

Distribution network reliability enhancement and power loss reduction by optimal network reconfiguration

Voltage instability, power imbalance, and unreliability are all caused by power interruptions and losses in the distribution system. The optimal reconfiguration of the distribution network is offered in this research as a solution to such challenges. The investigation is carried out using an actual distribution system in Kombolcha, Ethiopia. Modified shark smell optimization (MSSO) is used in the MATLAB environment to improve system reliability and voltage profile with low power loss. Tie switches are optimally placed to reduce power losses, total cost of outages, and reliability indices such as the system average interruption frequency index (SAIFI), system average interruption duration index (SAIDI), and expected energy not supply (EENS) all at the same time. The MSSO's effectiveness is demonstrated through a comparison with other approaches. Furthermore, a real-time digital simulator is used to implement the suggested task in real time with allowable mistakes in the results (RTDS).

Resilience in supply systems – What the food industry can learn from energy sector

Drastic events such as pandemics, earthquakes or other disasters not only threaten the immediate living conditions of people but also indirect circumstances such as energy supply, infrastructure and food production. To ensure that damage and failures in these areas do not lead to a disaster, special requirements are placed on this critical infrastructure. In this context resilience, which is defined as the resistance of a system to external effects, is required. A field that is indeed part of the critical infrastructure, but which has not been considered as intensively as the energy sector, is food production.The investigation focuses on how fundamental principles of thermodynamics, system theory and reliability theory can be applied to the modelling of food production processes to obtain a measure of resilience. Using known state and process variables from thermodynamics and electrical power engineering, analogous variables are derived for the food industry. These variables serve as an evaluation standard for a quality measure Q. In addition to system-theoretical considerations, it is investigated how existing evaluation criteria of power engineering, such as System Average Interruption Duration Index (SAIDI) and Customer Average Interruption Duration Index (CAIDI), can be transferred to food production.Design: The investigation focuses on how fundamental principles of thermodynamics, system theory and reliability theory can be applied to the modelling of food production processes to obtain a measure of resilience. Using known state and process variables from thermodynamics and electrical power engineering, analogous variables are derived for the food industry.Purpose: Drastic events such as pandemics, earthquakes or other disasters not only threaten the immediate living conditions of people but also indirect circumstances such as energy supply, infrastructure and food production. To ensure that damage and failures in these areas do not lead to a disaster, special requirements are placed on this critical infrastructure. In this context resilience is required.Findings: The aforementioned state and process variables serve as an evaluation standard for a quality measure Q. In addition to system-theoretical considerations, it is investigated how existing evaluation criteria of power engineering, such as SAIDI and CAIDI, can be transferred to food production.Originality: This paper fulfils an identified need to study a part of the critical infrastructure that has not been as extensively looked at as the energy sector, namely food production.

Energy trilemma in active distribution network design: Balancing affordability, sustainability and security in optimization-based decision-making

A significant reduction in greenhouse gas emissions entails complex trade-offs among economic, environmental and security objectives of the energy trilemma. The associated proliferation of distributed energy resources in power distribution networks requires optimized planning to ensure economic efficiency and security, where security is defined as the ability to withstand outages (reliability) and imbalances between generation and load (flexibility). This paper investigates the trade-offs among active distribution network design solutions in the energy trilemma. Storage, renewable and dispatchable generators are installed to minimize cost, interruptions and emissions via epsilon-constraint mixed integer linear program. The ramping capability of distributed energy resources is harnessed to provide flexible capacity to the surrounding grid, and to enable the transition from active distribution networks into microgrids with islanding capability. Decision-making strategies for selecting the best design from a Pareto-optimal set are contrasted based on the economic, sustainability and security of the design and operations. Applying these strategies to a Californian distribution network shows nonlinear trade-offs between the trilemma objectives, reducing both emissions and interruption durations by up to 64%. Remarkably, energy supply is diversified with up to 47% of local generation entailing a strong reduction in operating expenditures. While the increase in local generation can reduce the peak imports from the surrounding grid by 56% compared to a network without distributed energy resources, enforcing strict emission limits can lead to renewable exports that exceed the peak load by 130%. Sensitivity analyses identify the performance indicators which strongly influence the selection of the best design.

Application Study in the Field of Solutions for the Monitoring Distribution Transformers of the Overhead Power Grid

This paper will present the development and application of overhead transformers of the distribution grid, as well as the different technologies used for the gathering of electrical quantities, in the field of a monitoring solution. The solution reports the values of the quantities and alarms of operation remotely and almost in real-time. The development of this solution seeks to provide an electrical grid with greater reliability, proposing the reduction of KPIs (Key Performance Indicator), such as SAIDI (System Average Interruption Duration Index) and SAIFI (System Average Interruption Frequency Index), through more transparent monitoring of the behavior of the electrical distribution grid and its equipment. Through the research and development (R&D) project Urban Futurability, ENEL (Ente nazionale per l’energia elettrica) Distribution São Paulo seeks to apply the solution by implementing the concept of smart grids, an idea that has been growing each year by virtue of technological developments and the employment of new sensors in electrical distribution grids. Urban Futurability seeks to innovate the automation area, digital twin, and construction enhancement in the Vila Olímpia neighborhood of São Paulo, Brazil.

Advanced Metering Infrastructure—Towards a Reliable Network

In order to ensure continuous energy supply, Distribution System Operators (DSOs) have to monitor and analyze the condition of the power grid, especially checking for random events, such as breakdowns or other disturbances. Still, relatively little information is available on the operation of the Low Voltage (LV) grid. This can be improved thanks to digital tools, offering online processing of data, which ultimately increases effectiveness of the power grid. Among those tools, the use of the Advanced Metering Infrastructure (AMI) is especially conducive for improving reliability. AMI is one of the elements of the system Supervisory Control and Data Acquisition (SCADA) for the LV grid. Exact knowledge of the reliability conditions of a power grid is also indispensable for optimizing investment. AMI is also key in providing operational capacity for carrying out energy balance in virtual power plants (VPPs). This paper deals with methodology of identification and location of faults in the AMI-supervised LV grid and with calculating the System Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Index (SAIFI) on the basis of the recorded events. The results presented in the paper are based on data obtained from seven MV/LV transformer stations that supply over 2000 customers.

The influence of the type and size of the reactor and the influence of the heating interruption during curing on the solid composite propellant properties

AbstractThe solid composite propellant is a viscoelastic material that retains the treatment received during its all‐useful life. As a result, its manufacturing conditions induce differences in its final mechanical properties. The present study aims to evaluate the influence of the type and size of the reactor and the effects of the heating interruption during curing on the final mechanical properties of the propellant. Thus, four production processes with identical propellant formulations were performed in four different reactors. One of them was vertical, while the others were horizontal reactors. The heating interruption during curing was performed in 10 samples, at different moments of the curing process and with different duration. The study determines that vertical reactors tend to produce propellants less rigid than those produced in the horizontal type. In addition, the bigger the reactor size, the less rigid the propellant becomes. Finally, the heating interruptions at the beginning of the curing process tend to be insignificant. However, when they occur in an advanced stage of the curing process, they tend to hinder the curing progress, being more significant for interruptions of medium duration.

Neonatal resuscitation practices in Uganda: a video observational study

BackgroundNeonatal mortality, often due to birth asphyxia, remains stubbornly high in sub-Saharan Africa. Guidelines for neonatal resuscitation, where achieving adequate positive pressure ventilation (PPV) is key, have been implemented in...

Stochastic Planning and Operational Constraint Assessment of System-Customer Power Supply Risks in Electricity Distribution Networks

Electricity-distribution network operators face several operational constraints in the provision of safe and reliable power given that investments for network area reinforcement must be commensurate with improvements in network reliability. This paper provides an integrated approach for assessing the impact of different operational constraints on distribution-network reliability by incorporating component lifetime models, time-varying component failure rates, as well as the monetary cost of customer interruptions in an all-inclusive probabilistic methodology that applies a time-sequential Monte Carlo simulation. A test distribution network based on the Roy Billinton test system was modelled to investigate the system performance when overloading limits are exceeded as well as when preventive maintenance is performed. Standard reliability indices measuring the frequency and duration of interruptions and the energy not supplied were complemented with a novel monetary reliability index. The comprehensive assessment includes not only average indices but also their probability distributions to adequately describe the risk of customer interruptions. Results demonstrate the effectiveness of this holistic approach, as the impacts of operational decisions are assessed from both reliability and monetary perspectives. This informs network planning decisions through optimum investments and consideration of customer outage costs.

Replacing protein via enteral nutrition in a stepwise approach in critically ill patients: A pilot randomized controlled trial (REPLENISH pilot trial)

The optimal amount of protein intake in critically ill patients is unclear. The objective of this pilot trial is to assess the feasibility of a large randomized controlled trial testing higher versus lower protein intake in critically ill patients. In this pilot randomized controlled trial (REPLacing Protein via Enteral Nutrition in a Stepwise ApproacH in critically ill patients: A pilot randomized controlled trial (REPLENISH pilot trial), critically ill patients underwent 2-step screening for eligibility on ICU day 1 and 5. Patients with renal disease were excluded. Eligible patients were randomized into REPLENISH group (target protein 1.8-2.2gkg/day) and Standard group (target protein 0.8-1.0g/kg/day) from day 6-14 after ICU admission. Dietitians adjusted caloric and protein intake throughout the study period (Day 1-14) to maintain similar caloric targets of permissive underfeeding (40-60% of estimated energy expenditure) in both study groups. Of 704 patients screened at 3 centers in Saudi Arabia from May 2018 to May 2019, only 63 (8.9%) were eligible and 40 (5.7% of screened) were randomized with an average of 2 patients enrolled in the trial per month. Among eligible patients, the consenting rate was high at 89%. During the intervention period, patients in the REPLENISH group (N=21) had a modestly higher protein intake (median of 1.30g/kg/day (Q1 Q3: 1.11, 1.57)) than those in the standard group (median of 0.77g/kg/day (Q1 Q3: 0.57, 1.00); P=0.0004). Only 31.4% of patients in the whole cohort had >80% of prescribed protein. The duration of daily interruption of feeding was almost 4h in both groups. The 90-day mortality for the patient study cohort was 20.5%. Anthropometric and muscle strength measurements were performed in less than 50% of patients. This pilot trial highlighted several areas for improvement in the study protocol before launching a large randomized controlled trial. The restrictive eligibility criteria, the complex adjustments of protein and energy and some of the outcome measurements were identified as targets for modifications, to improve enrollment and generalizability and to enhance adherence to study interventions and measurements. CLINICALTRIALS. NCT03480555.

Preparatory Operation of Automated Distribution Systems for Resilience Enhancement of Critical Loads

This paper proposes a stochastic optimization model for preparatory operation of distributed energy resources that enhance the resilience of critical loads against extreme weather events. Adopting hurricanes as a case study of extreme weather events, a high-precision spatio-temporal hurricane impact analysis model is first developed to enhance the situational awareness of automated distribution systems and generate a set of hurricane-induced outage scenarios. A stochastic mixed-integer conic programming model is then developed for co-optimizing the preparatory schedule of distributed energy storage and distributed generation ahead of hurricane along with post-event decisions of restoring services to customers, while minimizing the expected cost of energy not served as the index to measure the resilience. The proposed model prioritizes the service restoration of critical loads by integrating customer interruption cost function, which captures the customer type and outage costs as well as interruption duration in making restoration decisions. Additionally, a conic power flow model is adopted to accurately capture network operation constraints in pre- and post-outage scenarios. Numerical results conducted on the IEEE 33-bus system show that the proposed model can enhance the performance of automated distribution systems in responding to hurricane-induced outages by efficiently utilizing grid resources to improve the resilience of critical loads.

Utility of Virtual Platform for Conducting Practical Examination for Medical Students During Covid Times: A Prospective Study from Gynaecology Department.

BackgroundAs the novel coronavirus 2019 (COVID-19) continues its pandemic surge globally along with its social distancing norms, the physical conduction of practical examinations for medical graduates and postgraduates has become difficult. Software-based systems and social media platforms could provide alternatives for ensuring regular medical education and exam-oriented assessments. In this context, we evaluated our own experience with virtual conduction of semester practical exams for medical graduates.Material and MethodsThis prospective study was conducted in Gynaecology and Obstetrics department. We employed live streaming educational video conferencing software for virtual consultation between medical students, patients (case presentations), internal and external examiners. The outcomes were evaluated in terms of conduction of various components of practical examination—Viva, case presentations, instruments, slides, specimen examination. Statistical analysis was performed by descriptive statistics through Microsoft Excel sheet.ResultsVirtual conduction examination/evaluation was performed on 150 medical students by examiners from a distant location. No problems occurred except few short duration (less than 5 min) interruptions due to internet connectivity issues. 125/150 (83.5%) of medical students and all examiners (2 internal and 2 external) expressed satisfaction with virtual medical evaluation.Conclusions83.5% of medical students and all examiners expressed satisfaction with virtual medical evaluation during this COVID pandemic. Our findings suggest that virtual conduction of practical annual medical exams through virtual video conferencing platform appears to be an optimal alternative during COVID pandemic.

Optimal operation and management of multi‐microgrids using blockchain technology

This paper tries to address the optimal operation of networked microgrid from the reliability perspective in a correlated atmosphere for the wind generators. The suggested approach performs based on unscented transformation in the form of a nonlinear projection and the heuristic method as the optimizer. The proposed structure is arranged as a complex constraint optimization problem with several targets seeing the varied objectives such as energy not supplied, system interruption frequency, system interruption duration and energy losses. Owing to the interrelated natural surroundings of multi-microgrids, it is a necessity for the microgrids to let the each other access the operation info and with the central unit. In this situation, it is quite wise to provide a secured construction made of the blockchain for the assurance of the reliability and adequate security of data sharing in the microgrids. With the aim of validation of the proposed model, an IEEE standard system is considered and divided into four interrelated microgrids with one side connection to the main grid. The simulation results show the high capability of the proposed framework for enhancing the operation and reliability indices. Moreover, it is seen that almost 0.6% and 0.77% additional cost is imposed to the system in the deterministic framework in the first and second scenarios, respectively.

Assessment of chest compression interruptions during advanced cardiac life support

AimTo identify potentially avoidable factors responsible for chest compression interruptions and to evaluate the influence of chest compression fraction on achieving return of spontaneous circulation and survival to hospital discharge. MethodsIn this prospective observational study, each resuscitation managed by mobile medical teams from August 1st, 2016, to August 1st, 2018 was video recorded using a body-mounted GoPro camera. The duration of all chest compression interruptions was recorded and chest compression fraction was calculated. All actions causing an interruption of at least 10 s were analyzed. ResultsTwo hundred and six resuscitations of both in- and out-of-hospital cardiac arrest patients were analysed. In total 1867 chest compression interruptions were identified. Of these, 623 were longer than 10 s in which a total of 794 actions were performed. In 4.3% of the registered pauses, cardiopulmonary resuscitation was interrupted for more than 60 s. The most performed actions during prolonged interruptions were rhythm/pulse checks (51.6%), installation/use of mechanical chest compression devices (11.1%), cardiopulmonary resuscitation provider switches (6.7%) and ETT placements (6.2%). No statistically significant relationship was found between chest compression fraction and return of spontaneous circulation or survival. ConclusionThe majority of chest compression interruptions during resuscitation were caused by prolonged rhythm checks, cardiopulmonary resuscitation provider switches, incorrect use of mechanical chest compression devices and ETT placement. No association was found between chest compression fraction and return of spontaneous circulation, nor an influence on survival. This was presumably caused by the high baseline chest compression fraction of >86%.

Increasing Electric Vehicle Penetration Using Smart Switching and Emergency Uprating

One of the key challenges facing distribution network operators today is the expected increase in electric vehicles. The increased load from EV charging will result in distribution assets becoming “thermally overloaded” due to higher operating temperatures. In addition to the issue of increased load, we have a limited understanding of the behavior and performance of the distribution assets and their potential to accept the increased load. It has been well acknowledged that EVs increase the network loading level, leading to a reduced system reliability performance. These results have not been quantified in a realistic case study, including actual cable rating and design properties. To address this gap, this paper proposes a novel methodology in the existing power network reliability evaluation framework, which quantifies the impact of different EV penetration levels on distribution network reliability, and the thermal performance of distribution cables. Novel approaches using smart switching technology and emergency uprating are proposed to reduce the peak power demand caused by EVs, in order to reinforce the reliability of the grid and to boost the maximum allowable EV penetration in the distribution networks. The methodology was applied using a case study on the modified EV-integrated RBTS (Roy Billinton Test System) bus four distribution network. The results showed that the negative impact of EVs on network performance can be mitigated by the implementation of smart switching technology. The peak demand under contingencies can also be accepted by the cables though emergency uprating. The frequency and duration of EV demand interruption was also significantly reduced. Thus, a higher EV penetration can be accommodated.

German S3-Guideline on the treatment of Psoriasis vulgaris, adapted from EuroGuiDerm - Part 2: Treatment monitoring and specific clinical or comorbid situations.

German S3-Guideline on the treatment of Psoriasis vulgaris, adapted from EuroGuiDerm - Part 2: Treatment monitoring and specific clinical or comorbid situations.

Analysis of smart grid technology application for power distribution system reliability enhancement: A case study on Bahir Dar power distribution

Reliability improvement of power distribution systems is a pre-request for economic and social development of any country. Currently, there is a rapid growth of industrial, commercial, residential and other service supplying institutions. All of these institutions need reliable power supply. Due to this, utilities must work hard and ensure that the customers are getting a reliable power supply. However, higher power interruption frequency and longer interruption duration are the most serious problem facing Ethiopian power distribution systems and this problem affects the daily activity of customers. In this paper, smart grid technology applications using optimal placement of switching/automating devices, network reconfiguration and rapid power restoration is performed to improve the reliability problem of Bahir Dar power distribution system. Optimal placement of switching/automating devices and network reconfiguration is determined by the Genetic Algorithm optimization technique using mat lab software. The rapid power restoration is carried out by Prim‘s Algorithm used for constructing the Minimum Spanning Tree in mat lab software. The study is tested at Bata the 34 bus feeder of Bahir Dar distribution system. The existing network is assessed and the reliability indices such as SAIFI, SAIDI, ASAI, CAIDI and EENS are evaluated using ETAP 12.6.0 software.

Individualized 6-Mercaptopurine Increments in Consolidation Treatment of Childhood Acute Lymphoblastic Leukemia: A NOPHO ALL2008 Randomized Controlled Trial

Introduction: In contemporary treatment protocols for childhood acute lymphoblastic leukemia (ALL), most chemotherapeutic agents are prescribed as a fixed dose per m2. 6-mercaptopurine (6-MP) is frequently used during consolidation therapy and mediates its effect through incorporation into DNA as thioguanine nucleotides (DNA-TGN), higher levels of which are associated with a decreased risk of relapse. In this randomized controlled trial on children with non-high risk ALL, we tested the hypothesis that individualized, toxicity-titrated 6-mercaptopurine (6-MP) increments during consolidation therapy with high-dose methotrexate were superior to the standard fixed-dose 6-MP regimen. The primary end point was minimal residual disease (MRD) positivity at end of consolidation, and the secondary end point was event-free survival. The trial was registered at clinicaltrials.gov (NCT00816049).Methods: Between January 2009 and March 2016 we randomized 392 children aged 1-17 years to experimental and 396 to standard therapy. Patients allocated to standard therapy received oral 6-MP (25 mg/m2/day) from day 30 to 85, while the experimental arm received stepwise increments with 25 mg/m2/day beginning on days 50 and/or 71 unless they had experienced dose-limiting myelosuppression (neutrophil count ≤ 0.5 x 109/L or thrombocyte count < 50 x 109/L) following the preceding dose of high-dose methotrexate (days 36 and 57). MRD was measured using PCR for T-cell ALL and flow cytometry for B-cell precursor ALL (or PCR, if flow was not technically possible). MRD positivity was defined as any detectable marker with PCR and more than 10 leukemic events with flow cytometry. As a measure of treatment intensity and physician and patient compliance, we analyzed concentrations of DNA-TGN and methylated 6-MP metabolites (MeMP) in blood samples collected throughout consolidation therapy. Analyses were carried out on an intention-to-treat basis.Results: In the experimental arm, 166 patients (42%) received one dose increment, and 62 (16%) received two. Of 387 patients in the experimental arm, 57 (15%) were MRD positive at end of consolidation versus 77 of 389 (20%) in the control arm (P=0.08). Five-year probability of event-free survival was 0.89 (95% CI: 0.85-0.93) in the experimental arm versus 0.93 (0.90-0.96) in the control arm (P=0.13). The median cumulative length of 6-mercaptopurine treatment interruptions was 7 days (IQR 2-12) in the experimental arm versus 4 (IQR 0-10) in the control arm (P=0.002), but duration of treatment interruption was not associated with risk of relapse (P=0.99). There were seven treatment-related deaths in the experimental arm versus three in the control arm (P=0.22), and none of the deaths in the experimental arm were related to 6-MP increments. At the final risk stratification on day 79, one patient in the experimental arm and seven in the control arm (P=0.07) had MRD values ≥0.1%, which is the cutoff for stratification to high risk treatment with stem cell transplantation. The mean DNA-TGN levels at end of consolidation in patients given zero, one, or two dose increments were 162 fmol/µg DNA (95% CI 144-179), 237 (194-280), and 293 (156-430) respectively, P<0.0001. The corresponding MeMP values were 1 879 nmol/mmol Hb (1 397-2 360), 5 930 (4 368-7 492), and 12 173 (7 625-16 721), P<0.0001.Conclusion: Despite 6-MP dose intensifications in 58% of patients in the experimental arm and a strong association between dose increments and DNA-TGN levels, as well as a non-significant improvement in MRD at end of consolidation, we found no survival benefit from individualized 6-MP increments compared to standard therapy. DisclosuresNo relevant conflicts of interest to declare.

Current status and influencing factors of nursing interruption events.

To investigate the status of nursing interruption events during medicine administration and to analyze the factors influencing interruptions. The nursing drug delivery process was divided into 3 segments: the processing of doctors' orders, drug allocation, and bedside drug administration. The frequency, source, type, and outcome of interruption events during these 3 segments were observed. The interruption time and medication errors caused by interruptions were analyzed. The structural observation method was used to observe the 3 steps of the drug delivery process. The observations were performed between 8:30 and 10:30 and between 13:30 and 14:30. Count data are described as frequency, composition ratio, and cumulative percentage. R×C contingency table, t tests, and analysis of variance were used to analyze the data. In 270 hours of observation, 3424 nursing interruptions occurred, for a mean of 12.68 interruptions per hour. The mean (SD) interruption time was 28.03 (11.01) seconds, and the total duration of drug administration interruptions was 26.65 hours, accounting for 9.87% of the total observation time. The sources of interruption events were as follows: family members, the environment, doctors, patients, colleagues, the nurses themselves, and others; of these interruptions, 2340 were low-priority events (eg, visitor inquiry, telephone call, consultation, discharge questions), accounting for 68.34%. The incidence of medication errors due to interruptions was 1.139%. Nursing interruption events occur frequently, come from many sources, have complex causes, and commonly lead to negative outcomes. Interruption also has a time cost and can directly lead to medication errors.