High-tension electrical-arc-induced thermal burns caused by railway overhead cables

Impact of DC Transient Disturbances on Harmonic Performance of Voltage Transformers for AC Railway Applications

This paper analyzes the impact of typical DC transient events occurring in railway grids on the frequency performance of instrument transformers (ITs) installed onboard trains and in AC substations for power quality (PQ) applications. PQ monitoring in railway systems is an issue of great interest because it plays a key role in the improvement of energy efficiency. The measurement chain for the PQ measurements, at 15 kV at 16.7 Hz and 25 kV at 50/60 Hz, commonly includes ITs to scale the voltage to levels fitting the input of the measurement units. Nevertheless, the behavior of ITs in the presence of PQ phenomena represents an open issue from a normative point of view, even for those installed in conventional AC power supply systems. In this context, the paper presents a possible definition of DC transient disturbances test waveforms, a measurement procedure, and a setup to assess the impact of these disturbances on the harmonic performances of ITs for railway systems. Preliminary experimental tests carried out on two commercial ITs under wide ranges of variation for the amplitude and the time duration of DC disturbances show that, in some cases, the error introduced in harmonic measurements can exceed 100%.

Train surfing and other high voltage trauma: differences in injury-related mechanisms and operative outcomes after fasciotomy, amputation and soft-tissue coverage

BACKGROUND

In the context of scarce reports on train surfers among high voltage electric injuries, we conducted a retrospective review between January 1994 and December 2008.

METHODS

After matching for inclusion criteria we reviewed patient records of 37 true high voltage injuries (12 train surfers [TS] and 25 other high voltage injuries [HV]).

RESULTS

TS were significantly younger (TS 15.8 years vs. HV 33.3 years, p<0.0001), and had a greater %TBSA (TS 49.7%TBSA vs. HV 21.5%TBSA, p=0.0003) without affecting the median length-of-stay (TS 52 days vs. HV 49 days) or number of operations (TS 4 vs. HV 3). TS had different injury patterns, with a higher percentage of affected extremities (TS 72.9% vs. HV 52.0%, p=0.0468) and associated injuries (TS 58% vs. HV 20%, n.s.) than HV. Both groups demonstrated comparable fasciotomy (TS 71.4% vs. HV 55.8%) and amputation rates (TS 17.1% vs. HV 15.4%). While TS required less flaps (TS 3/12 vs. HV 18/25; p=0.0153), soft-tissue reconstruction revealed an overall low incidence of complication rates (one partial pedicled flap loss and two total free flap losses).

CONCLUSIONS

Train surfers have proven to be a distinct group of patients among high-voltage injuries notably as a result of a younger age, a shorter electric contact duration and higher velocity-induced trauma. With a possibly declining trend of train surfing-related accidents in an aging society, it will be interesting to see if emerging economies will face comparable phenomena, for which prevention strategies remain key.

Electrocution by arcing: a nonfatal case study

Accidental electrocution during working activities account for a considerable amount of morbidity and mortality. Workers often misjudge the danger of electric wires or high-tension power cables, thereby exposing themselves to electrocution hazard. This article describes a nonfatal case of injuries by arcing from high-tension power-line cables involving a young farmer who was thrashing an olive tree by means of aluminum ladder. The circumstances surrounding the manner of electrocution and the features of electric injuries are presented and discussed.

"Train surfers": analysis of 23 cases of electrical burns caused by high tension railway overhead cables

The term "train surfers" describes a group of adolescents from the outskirts of the city of Rio de Janeiro, who are compelled by the overcrowded railway trains to travel on the roofs of the wagons. Collision with electrical high-tension wires is a relatively frequent occurrence, causing extensive and complex injuries. This study analyzes this clinical and surgical phenomenon which has caused over 100 fatalities in more than 200 registered accidents over the past 10 years.

Electrical injury from subway third rails: serious injury associated with intermediate voltage contact

BACKGROUND

Railway and subway-associated electrical trauma is rare and typically involves high voltage (> 20,000) arc injuries. Not all rail systems utilize such high voltage. We report 16 cases of electrical trauma due to 600 V direct contact with subway 'third' rails.

METHODS

A case series of injured patients presenting to Shriners Burns Institute, Boston or Massachusetts General Hospital between 1970 and 1995 was retrospectively analyzed.

RESULTS

A total of 16 cases was identified. Among seven subway workers, the mechanism of rail contact was unintentional by a tool, a hand or by falling; no deaths occurred. Among nine non-occupational victims, injuries involved suicide attempts, unintentional falls, or risk-taking behavior. This group suffered greater burn severity, operative procedures, and complications; three deaths occurred.

CONCLUSIONS

This is the largest report series of direct electrical trauma from a subway third rail. The high morbidity and mortality from this 600 V contact suggests that the traditional classification of low voltage (< 1000 V) exposure can be subdivided to reflect the serious and lethal potential of intermediate range exposures compared to household range exposures (0-220 V).

Intracerebral venous thrombosis and hematoma secondary to high-voltage brain injury

We report the case of a 19-year-old male who sustained an electrodynamic (16.67 Hz) high-voltage (15,000 V) railway overhead cable injury. He lost consciousness 30 minutes after contact and died secondary to brainstem herniation as a result of intracerebral swelling within 8 days. Repeated cranial computed tomography revealed a huge hemispheric mass bleeding accompanied by subarachnoidal hemorrhage. Additionally, necropsy showed an extensive thrombosis of the adjacent cerebral veins. The pathophysiological mechanism of this unusual injury is discussed.

Pattern of burn injury in hang-glider pilots

High-voltage electrical injury has been well documented in a number of situations, such as the occupational hazard of linesmen and construction workers, and in the context of overhead railway power lines. Two cases of hang-glider pilots contacting 11,000-volt power lines have recently been treated in the Royal Brisbane Hospital Burns Unit. They demonstrate an interesting pattern of injury, not described in current burns literature, involving both hand and lower abdominal burns. Both patients sustained full-thickness patches of burn injury, with underlying muscle damage and peripheral neurological injury. This distribution of injury seems to be closely related to the design of the hang glider.

A clinical study of electrical injuries

Over a period of 10 years (January 1983 to December 1992), 173 patients with electrical burns were admitted to our Burn Center, constituting 6.8 per cent of acute admissions. There is a relative abundance of data in the medical literature concerning electrical burns, clearly depicting the local characteristics and peculiarities in different countries or societies. Our purpose is to present some statistical, epidemiological data from a Burn Center in China which has a multitudinous population, as well as to compare our data with that from other countries. Our data show that prevention and early wound management of electrical burns are very important in decreasing this incidence and the subsequent tissue amputation rate.

Very deep burns of the hand due to low voltage electrical laboratory equipment: a potential hazard for scientists

A low voltage (24 V) electrical deep burn of the hand injured a professor of applied physics when performing an experiment in his laboratory. The potential hazard of the equipment is described, the injuries are reported and the literature is reviewed.