Construction risk assessment is the final and decisive stage of risk analysis. When highly changeable conditions of works execution are predicted, risk should be evaluated in the favorable, moderate, and difficult random conditions of construction. Given the random conditions, the schedule and cost estimate of the construction are developed. Based on these values, the risk of final deadline delay and the risk of total cost increase of construction completion are calculated. Next, the charts of the risks are elaborated. Risk changes are shown in the charts and are analyzed in the range [1, 0].

This paper addresses the issue of antibacterial drugs, estrogens and cytostatic drugs’ presence in

surface waters and their influence on animals. The ecotoxicity and the impact of three active compounds: ciprofloxacin, 17α-ethinylestradiol and 5-fluorouracil on protozoa, crustaceans and fish were examined. Acute

tests (crustaceans’ immobilization test, fish survival test, enzymatic test on Daphnia magna) and chronic tests

(growth test on protozoa, reproduction test on crustaceans and juvenile growth test on two species of fish) were

performed. Acute toxicity studies revealed diversified species - sensitivity to the tested compounds. Crustaceans Artemia salina were the most resistant to all three pharmaceuticals. Fish also demonstrated low sensitivity

to ciprofloxacin and 5-fluorouracil (LC(EC)50-96h > 100 mg/l). In the survival tests, the greatest harm in respect

to fish and crustaceans was demonstrated by 17α-ethinylestradiol, and in the enzymatic tests - by ciprofloxacin.

In all chronic tests, the toxic effects of drugs were proven. Tested compounds limited reproduction of crustaceans and growth of protozoa and fry. The risk assessment, conducted on the basis of the PEC/PNEC quotient,

showed a significant risk in relation to aquatic animals caused by the presence of 17α-ethinylestradiol and

5-fluorouracil in concentrations detected in surface waters.

Environmental risks associated with Co, Cr, Cu, Mn, Ni, Pb, V and Zn in street dust collected from Baotou, a medium-sized industrial city in a semi-arid area of northwest China, were assessed by using enrichment factor and the potential ecological index. Their spatial distributions and sources in the dust were analyzed on the basis of geostatistical methods and multivariate statistical analysis, respectively. The results indicate that street dust in Baotou has elevated heavy metal concentrations, especially of Co, Cr, Cu, Pb and Zn. Co in the dust was significantly enriched. Cr and Pb were from moderate to significant enrichment. Cu and Zn were from minimal to moderate enrichment, whereas Mn, Ni and V in the dust were from deficient to minimal enrichment. The ecological risk levels of Co and Pb in the dust were moderate to considerable and low to moderate, respectively, whereas those of other heavy metals studied in the dust presented low ecological risk. Different distribution patterns were found among the analyzed heavy metals. Three main sources of these heavy metals were identified. Cr, Mn, Ni and V originated from nature and industrial activities. Cu, Pb and Zn derived mainly from traffic sources, and Co was mainly from construction sources.

This study presents a fuzzy analytic hierarchy process (FAHP) by integrating analytic hierarchy process (AHP) and fuzzy cognition to evaluate the construction risks of tunnel portals. Wuguanyi Tunnel is taken as the research objective to validate the performance of the proposed method. The result shows that the proposed decision making method can effectively identify risk factors and determine the risk level during the construction of tunnel portals. Finally, the corresponding control measures during the construction of the Wuguanyi Tunnel portal are proposed according to the risk assessment results.

The paper concerns a risk assessment and management methodology in critical infrastructures. The aim of the paper is to present researches on risk management within the experimentation tool based on the OSCAD software. The researches are focused on interdependent infrastructures where the specific phenomena, like escalating and cascading effects, may occur. The objective of the researches is to acquire knowledge about risk issues within interdependent infrastructures, to assess the usefulness of the OSCAD-based risk manager in this application domain, and to identify directions for further R&D works. The paper contains a short introduction to risk management in critical infrastructures, presents the state of the art, and the context, plan and scenarios of the performed validation experiments. Next, step by step, the validation is performed. It encompasses two collaborating infrastructures (railway, energy). It is shown how a hazardous event impacts the given infrastructure (primary and secondary eects) and the neighbouring infrastructure. In the conclusions the experiments are summarized, the OSCAD software assessed and directions of the future works identified.

The paper concerns the assessment of blackout hazards in the power systems. On the basis of statistical data from more than one hundred failures in power systems that affected the world in the last fifty years, the analysis was carried out regarding the number of people affected by a blackout, power losses in the system, duration of a failure and its direct causes. The paper also describes the methodology of risk analysis and vulnerability analysis of the extraordinary events occurrence in electrical power systems resulting in failures. The structure of risk analysis was based on the bow tie model, identifying threats, unwanted events, barriers and consequences of a system failure. Moreover, particular attention was drawn to the impact of the power reserve deficit in the Polish Power System in the coming years on the increase in the risk of a blackout failure.

Uranium concentrations in groundwater taken from private drilled wells have been never determined in Poland, implying a lack of available data to quantify the human exposure to U through drinking water consumption, especially in rural areas influenced by mining activities. The main aim of the study was the assessment of human health risk related to the consumption of well waters containing U, collected from selected rural areas of the Lower Silesian region (Poland). The random daytime (RDT) sampling method was applied to the collection of well waters from three control study areas (CSA): Mniszków (CSA-A), Stara Kamienica/M. Kamienica/Kopaniec (CSA-B) and Kletno (CSA-C). The analyses of RDT samples were performed by validated method based on inductively coupled plasma mass spectrometry (ICP-MS). Uranium concentration ranges in well waters and the estimated geometric means for individual control study areas were: 0.005-1.03 μg/L and 0.052 μg/L (CSA-A), 0.027-10.6 μg/L and 0.40 μg/L (CSA-B), and 0.006-27.1 μg/L and 0.38 μg/L (CSA-C). The average and individual chronic daily intakes (CDI) of U by drinking water pathway (adults/children) were in the ranges of: 0.0017-0.013/0.0052-0.040 μg · kg-1 · day-1 and 0.0002-0.90/0.0005-2.71 μg · kg-1 · day-1. The average %TDI and ranges of individual %TDI (adults/children) were: 0.17%/0.52% and 0.02-3.4%/0.05-10.3% (CSA-A), 1.3%/4.0% and 0.09-35%/0.27-106% (CSA-B), and 1.3%/3.8% and 0.02-90%/0.06-271% (CSA-C). The estimated average CDI values of U through well water are significantly lower than the TDI (1 μg · kg-1 · day-1), while for individual CDI values the contribution to the TDI can reach even 90% (adults) and 271% (children), indicating essential human health risk for children consuming well water from private drilled wells located in CSA-B and CSA-C (5.3% of total number of samples collected).

The influence and the potential risk due to hidden faults of a relay protection system on power supply in distribution systems are paid more and more attention to. A probability analysis method is used to analyse fault characteristics and action mechanism of dominant faults, hidden misoperation and non-operation of the relay protection systems, and failure probability model of relay protection system is constructed and simplified. The effects of dominant faults, hidden misoperation and non-operation of the relay protection systems on the reduced power supply load power are analysed, and a probabilistic model for reduced power supply load power is constructed by three parts corresponding to dominant faults, hidden misoperation and non-operation. A probability calculation method of power supply risk occurrence due to hidden faults of relay protecttion system is proposed considering the fault probability of the relay protection systems, the frequency of the hidden faults occurring in operation period, the reduced power supply load power or load power outage, and the connection mode of the in-lines, out-lines and transformers in a substation. The feasibility and applicability of the proposed method for estimation of risk value probability of the relay protection systems is verified by two studied examples.

The offshore Oil & Gas Industry is very important to the European Union economy. Therefore it must be properly monitored and protected, and legal regulations must be in place. Directive 2013/30/EU implemented on July 18, 2018 obliged EU Member States as well as operators and owners of oil and gas related activities in sea areas to implement solutions reducing the risk of major accidents, minor accidents and dangerous situations.

The purpose of the article is to identify all the possible hazards that may occur during oil and gas operations in marine areas and attempt to assess the risk along with providing effective responses in the event of its occurrence by preparing appropriate plans for responding to the situation. For the completion of the main purpose of the work the provisions of Directive 2013/30/EU of the European Parliament and of the Council of 12 June 2013 on safety of offshore oil and gas operations were presented and analyzed using the Hazard Identification method, the analysis of available reports prepared by the European Commission, classification bodies and own experience obtained while working in the offshore industry during searching, drilling and oil and gas production located under the seabed at the Polish Economic Executive Zone. The study presents numerous analyses and comments, which were presented in the form of graphs and tables, based on international reports and own experience gained while working in an offshore company.