Noise-Induced Hearing Loss (NIHL) is a global issue that is caused by many factors. The purpose of this study was to survey noise level to identify NIHL and its relationship with other factors in cement plants in Vietnam. Noise level was measured at one cement plant and three cement grinding stations located in the South of Vietnam. The audiometric data of exposed workers were surveyed to determine NIHL. Finally, the relationship between NIHL and noise level in cement plants was determined. The results show that noise level in almost all processes exceeded the permissible exposure limit (PEL). In this study, 42 cases (10% of exposed workers) with occupational NIHL were found with mean age (SD) of 49 (9.0) years. All NIHL cases were found in the departments in which the noise level exceeded the PEL, which included quarry (n = 16), maintenance (n = 12), production (n = 10), co-waste processing (n = 3) and quality assurance (n = 1). There was a positive and significant correlation between the NIHL and the excessive noise exposure in the cement plants (r = 0.89, p = 0.04).

Fire is defined as an extremely hazardous event, causing a threat to life and health of persons, but also damage to the economic sphere. It has been shown many times that fire can occur anywhere and at any time. In order to minimize the risk of fire manifestations, it is necessary to understand its course. In technical practice, computational models are used to determine the partial manifestations of fire, such as fire spread rate, smoke generation rate in the burning area, formation of toxic burning products, flame height, and others. One of the important characteristics is also the energy balance in the burning area relating to the character of burning material, access of oxygen necessary for exothermic reaction of burning, and reaction of the installed safety devices. In this paper we will point out the fire safety of the building. The FDS (Fire Dynamics Simulator) model is recently used in practice, and its advantage is the possibility to model fire even in large and atypical spaces. The contribution of this paper is the practical application of fire safety of construction using the FDS Model, to reduce the cost of fire safety for the structure being constructed. Attention was paid to evaluating how the heat energy that is released during a fire can be influenced by the installed stable fire-extinguishing equipment, taking into consideration the fire resistance of the building structures.

Air pollution associated with suspended particles has become a significant concern in Vietnam recently. The study aimed to (1) investigate dust sources; (2) measure concentration levels of Total Suspended Particulate (TSP), Particulate Matter (PM) fractions; (3) identify silica levels and the correlation with respirable particles at a cement grinding plant in Vietnam. A total of 312 samples (52 TSP, 160 PMs) at 13 processes were measured using the direct-reading dust meter. The silica composition was analyzed in a certified laboratory using the X-ray fluorescence (XRF) technique. SPSS version 26 for Window was used to analyze the data. The operations of the cement grinding plant created multiple dust sources from the jetty to the cement dispatch process. The TSP levels ranged 0.06–38.24 mg m⁻³, and 40.38% (n = 21) TSP samples exceeded the Permissible Exposure Limit (PEL) for an 8-h working shift. Besides that, there was a wide range and significant concentration levels of PMs in the cement processes. The levels of PMs were PM₁ (0.00–0.06 mg m⁻³), PM_2.5 (0.01–0.83 mg m⁻³), PM₄ (0.02–4.59 mg m⁻³), PM₇ (0.03–16.94 mg m⁻³), and PM₁₀ (0.04–26.85 mg m⁻³). The highest mean levels of PMs factions were measured at the pre-grinding process. The inefficient operation of the dust collector contributed a significant factor to the dust dispersion in this process. The silica’s mean (SD) composition in respirable dust was 20.4% (0.86) and was not significantly different amongst the processes. There was a significant correlation between the levels of respirable dust and silica exposure in the cement grinding plant (r = 0.99). The improvement of indoor air quality is needed to prevent health effects on cement workers.

This paper investigates the possibilities of using an agent-based evacuation model to analyse the formation of queues at the exits of enclosed spaces and the evacuation process of people. The aim is to investigate how the density of people in a crowd affects the safe movement of people and how the width, number, and location of exits affect evacuation time. The analysis was carried out using the Pathfinder evacuation model, which provides two modes to simulate the movement of people: steering and SFPE. An enclosed space of 20 m × 30 m was investigated. First, the differences between the modes of the evacuation model to simulate the movement of people were compared. Then, the steering mode with limited door flow was set and the effect of the width, number, and location of the exits with a total width of 4 m on the evacuation time was investigated. The results of this study highlight differences in the simulation of the movement of people according to the different modes and provide valuable information for the design of safe escape routes. Proper design of escape routes can prevent an adverse situation that could arise when evacuating a large number of people.

Electricity is the most important form of household energy and one of the most important forms of energy for industry and transport. Electrical distribution in construction and transport is almost exclusively implemented using electrical cables. One of the unresolved problems associated with electrical cables is the release of smoke and the resulting reduction of visibility in case of fire in the area. In this study, a new approach was developed to assess the reduction of visibility in an area affected by an electrical cable fire. This approach is based on the determination of the critical ratio of smoke volume (in the smoke layer and exhausted from the fire compartment) to the length of the burning cable, through which the visibility of reflective and illuminated signs was reduced to a lower limit value (a standard of 10 m). The input data for this approach was the extinction area of the smoke released from one meter of burning cable and the length of the cables in the area. This approach was used to test two power cables (CHKE-V J3x1.5 and CHKE-R J3x1.5) and one signal cable J-H(St)H 1 × 2 × 0.8 with the B2_ca, s1, d1, a1 fire reaction class. The smoke extinction area of the examined cables was determined using a cone calorimeter at a heat flux of 50 kW/m². The obtained data showed that in order to maintain a visibility of 10 m for reflective signs, the critical ratio of smoke volume to length of burning cable was 7.5 m³/m. For illuminated signs, the critical ratio was 2.8 m³/m. The relationship between burning length and visibility allows the calculation of visibility in the fire compartment affected by cable fire only from cables length.

The increasing use of wooden cladding in multi-storey buildings raises critical fire safety concerns, especially in ventilated façade systems where the chimney effect can accelerate vertical flame spread. This study combines theoretical analysis with three full-scale fire tests to investigate key factors influencing fire propagation, including the influence of façade design details. Results show that poorly constructed lintels and jambs significantly accelerate flame entry into ventilated cavities, while wooden fire barriers—despite being combustible—can delay flame spread if properly installed. These findings inform design recommendations and underscore the need for more robust fire safety strategies in modern timber construction.