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High-voltage overhead lines produce low-frequency electromagnetic fields around them. These fields are easy to compute wherever the line route is straight, as opposed to places where its direction is changed. The purpose of this paper is to perform a numerical analysis of an electromagnetic field occurring along a high-voltage overhead line at the places of the changed direction and to compare the results with the exposure limits for low-frequency electromagnetic fields in order to assess their effects on living organisms.

The computation was conducted in the MATLAB SW by means of a combination of integral and differential methods in a three-dimensional (3D) arrangement, taking into account the location and shape of the tower. Special procedures within the MATLAB software had to be coded.

Within the research, the following electromagnetic field quantities were computed: the distribution of electric field strength, magnetic flux density, Poynting vector, electric potential and surface charge density. The results obtained indicate the influence of both the line route changing its direction and the deviation tower location on the electromagnetic field around the tower.

In order to shorten the computation time, it was necessary to achieve a minimum number of degrees of freedom by adjusting the real shape of both the cross-section of the deviation tower beam and the conductors. In some further research, attempts could be made to further optimize the results by using the real shapes of the cross-section of the deviation tower beam and the conductors. Furthermore, it could be beneficial to shorten the set distance between two adjacent nodes in order to obtain a finer mesh while still achieving an optimal ratio between the number of nodes and the computation time.

The Czech Regulation no. 1/2008 Coll., concerning protection of health against non-ionized radiation, stipulates 100 μT to be the maximum safe value of magnetic flux density in case of an uninterrupted exposure and frequency of 50 Hz. The investigated area did not exhibit values exceeding this limit. The same was true for the maximum permissible level of electric field strength being specified at 5,000 V/m.

Similar problems are often solved by means of FEM in 2D arrangements. However, when applying this method for conductors passing through a large 3D area, it is difficult to model an optimal 3D mesh within the conductors and the tower beams. This research shows that the application of integral methods reduces the complexity of the generated mesh. Unlike FEM, requiring the generation of a 3D mesh, the integral method only requires a surface mesh on the conductors and tower beams, thus significantly reducing the number of degrees of freedom. FEM only remains necessary for areas adjacent to the tower beams and conductors.

May 5, 1972 Factory — Statutory duty — Breach — Fume — Prolonged inhalation of low concentration — Chronic lung illness — Employer's actual or constructive knowledge of health hazard — Whether to be determined up to time when action brought — Limits of statutory duty — Whether need to act on expert speculation unaccompanied by hazard warning — Factories Act, 1961 (9 & 10 Eliz. II, c.34), ss. 4(1), 63(1).

This paper aims to assess the Jos Plateau Tin-mining region as an abandoned mine area being used for housing development with a view to make recommendations.

Utilising secondary data, which maps out ten different locations in the region, this paper highlights the level of radioactive substances (X-ray, beta and gamma rays) and the presence of heavy metals in the environment, abandoned mines, home for the people as well as housing development within a derelict region. Face-to-face interviews were conducted with heads of selected settlement within the Jos Plateau Tin-mining region.

Subsequent analysis shows that the radioactive substances exceed the international standards and therefore have a serious impact on the health of the local population who reside in the affected area. This is particularly significant as people use the contaminated soil as a basic material for their homes as well as farming and food production.

With overpopulation of neighbouring city and rising house prices, an increasing number of people have moved to the Tin-mining areas often without any knowledge about the perils of contaminated soil. At the same time, the planning authority has no presence in the affected area, as it falls outside its jurisdiction.

However, there is an urgent need to address this problem and prevent people from moving to this area, otherwise this would become a serious long-term human catastrophe.

Drawing from international experience, the paper argues that it is possible to develop housing in former Tin-mining areas but require careful remediation and engagement by the public and private sector.

The discussion in this paper makes a case for appropriate physical planning measure as people build their homes on the abandoned Tin-mining areas, with the presences of heavy metals and radioactive substances which are dangerous to human health where the governments have not made provision to address the problem. It is a bridge linking a previous paper on the environment and now consideration on housing/home which together form part of an ongoing PhD research “A potential application of spatial planning in Jos, Nigeria”.

Nigeria, a prominent country in Sub-Sahara Africa, is plagued with a protracted, erratic and low power supply. The purpose of this paper is to present an experimental investigation of the noise levels and pollutants’ (CO, CO₂ and particulate matter (PM_2.5)) concentrations associated with the prevalent use of diesel-powered generators in the country. It is aimed to provide information on the level of gaseous, particulate and noise pollutants that are related to diesel-powered generators that could assist in policy formulation and create public awareness on the possible health risks.

Diesel-fueled generators (105) with age and installed capacity ranging from 0.5 to 14 years and 10 to 500 kVA, respectively, were engaged in this work at Sango area of Ogun State, Nigeria. Standard measuring instruments were placed at 1 m from the diesel-powered generators to determine the noise levels and concentrations of CO, CO₂ and PM_2.5.

Ranges of 72.6–115.6 dB, 19–198 ppm, 501–5,805 ppm and 221–492 µg/m³ for the noise level, CO, CO₂ and PM_2.5 concentrations, respectively, were obtained. Both the averages and ranges of the noise levels and pollutants’ concentrations were considerably higher than the recommended maximum limits. Thus, this study substantiated the pollution of ambient noise and air because of the operation of diesel-fueled generators. Furthermore, the health risks connected to the exposure to CO and PM_2.5 as implied via the evaluation of the air quality index revealed very unhealthy and hazardous conditions, respectively.

The measurement of the pollutants’ concentrations at the tips of the exhaust pipes of the diesel-powered generators was desirable but could not be achieved using manually logged devices. Nonetheless, adequate pollutants’ concentration data that satisfactorily represent the level of air pollution associated with diesel-fueled generators’ operations were obtained at around 1 m from the exhaust pipes.

The study provided additional knowledge on the levels of noise and pollutants, and the public health risks connected to the operations of diesel-powered generators that will be beneficial to the public and policymakers.

The results revealed a considerably high level of noise and air pollution, and the inherent environmental and public health problems connected to diesel-powered generators’ usage in Nigeria. This could serve as a viable tool for formulating environmental policy and providing the necessary societal awareness in this regard.

This paper studies the integration of production and maintenance planning for an unreliable production system subject to gradual deterioration. The goal of this planning is to optimize production and maintenance while reducing workers' exposure to silica dust. The objective will therefore be to offer manufacturers a production strategy that minimizes the total cost of production while considering the health of employees.

Adequate prevention methods are determined and integrated into the granite transformation production system, which evolves in a stochastic environment. With the failure rate of the dust reduction unit being a function of its degradation state, the authors solve the optimization problem using stochastic dynamic programming in the context of nonhomogeneous Markov chain.

The resulting planning strategy shows that one can manage stock optimally while ensuring a healthy environment for workers. It ensures that crystalline silica prevention equipment is available and effective and defines the production rate according to a critical threshold, which is a function of the age of the dust reduction unit.

This article illustrates that it is possible to integrate silica dust reduction measures into production planning while remaining optimal and ensuring the health of operators. In the present study, the machined granite was assumed to be a natural granite, and production takes place in a closed environment.

The originality of this work lies in its development of an optimal joint production and maintenance strategy, which considers limits of exposure to crystalline silica. An optimal production and maintenance control policy considering employees' health is therefore proposed.

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

In counterparty credit risk management for swaps, forwards, and other derivative contracts, it is recognized that most common applications of credit exposure measurement suffer from the bias that counterparty default is independent of the amount of exposure. Stress tests are often proposed to compensate for this bias, but these measures tend to be arbitrary and cannot be uniformly applied to setting prices and limits as readily as more standardized approaches. The author proposes a framework in which standard measures of counterparty exposure are conditioned on default probabilities. These conditional measures thus account for “rong way” exposures, but fit naturally into current applications.

The Secretary of State for the Environment, after consulting with the Advisory Committee established under the Radioactive Substances Act 1948, makes these regulations in exercise of his powers under Section 5(2) and (3) of that Act, and under the Radioactive Substances Act 1948 Appropriate Minister Designation (No. 2) Order 1964, and of all other enabling powers:—

Summarises the environmental cadmium loading, human body cadmium (Cd) burden and the biological indicators of the early‐stage health effects induced by exposure to cadmium on the population of Daye county in China. Claims that urinary calcium and urinary low molecular weight protein are good biological indicators for the detection of the early‐stage renal dysfunction and recommend that the prevention and treatment of cadmium pollution be incorporated into primary health care. Cost‐benefit analysis of reduction of Cd emissions from the non‐ferrous smelter in Daye county indicates that the benefit‐cost ratio taking into account both direct health costs and indirect costs is far in excess of unity.

The attention of all concerned is drawn to the need for guarding against the effects of poisonous fumes when using chemical fire extinguishers of the types usually carried in civil aeroplanes. One of the dangers to be guarded against is that at low concentrations the fumes may have no smell, or such smell as there is may not be unpleasant, and may not suggest that breathing the air is in any way dangerous. Exposure for half an hour or so to such fumes may nevertheless produce subsequent ill effects, though none may be noticed until some hours after the exposure has ceased.