Background: Electrical injuries are rarely happened but it makes more harmful lesions comparing to other thermal injuries. The aim of this study was to report electrical burned patients according to electrical voltage in Shahid Motahari Burn Center.Methods: This Routine data base study was performed on patients with electrical burns which were admitted to Shahid Motahari Burn Center from April 2010 to March 2012. Demographic and clinical data had gathered from medical records. Association between voltage and morbidity or mortality was evaluated used SPSS v. 16.Results: Mean total body surface area of 287 patients (283 (98.60%) male and 4 (1.4%) female) with mean age of 30±0.7 years was 13.56±0.76% (range 1-100). There were 203 patients (70.7%) with low and 84 patients (29.31%) with high voltage injury. There was significant association between voltage and place of injury (p=0.001).Conclusion: High voltage injuries constitute large number of electrical injuries which more of these injuries occurred outdoor and in workplace and need more hospitalization. High voltage injuries are related with more amputation, so people and authorities should pay more attention to such injuries.

The mechanical, thermal, morphological, dynamical mechanical and electrical properties of polymeric insulators are tested and reported. Low density polyethylene (LDPE), ethylene-propylene-diene monomer (EPDM) and blends of LDPE/EPDM are known polymers for use as low, medium and high voltage insulators. Several formulations containing EPDM and LDPE were prepared. EPDM was blended with LDPE in different weight ratios of LDPE/EPDM (100/0, 80/20, 60/40, 50/50, 40/60, 20/80, 0/100). The change in Haake-viscosity mixing torque with time for different blend compositions was obtained. The torque at any time is dependent on the blend composition. For EPDM the observed torque is directly influenced by its cross-linking density. However, for LDPE or blends of high percentage of LDPE the influence of cross-linking density on torque is relatively low. The mechanical properties of cross-linked EPDM are weaker than LDPE. Therefore changing the cross-link density of EPDM will not affect the blend properties significantly especially at high LDPE content. A drop shape analysis system G l0 (Kruss-USA) was used for hydrophobicity studies. Studies illustrate that in LDPE/EPDM blends, tensile strength of the blends are higher than either polymer component alone. But the synergism effect in LDPE/EPDM compound is stronger than HDPE/EPDM. Also the blends of LDPE/EPDM show good breakdown voltage strength and heat resistance comparing to LDPE. The result of mechanical measurement shows that mechanical properties such as tensile strength, modulus and elongation-at-break of blends can be enhanced with increase in LDPE in the formulation. Also tests were conducted to study various properties (mechanical, surface, electrical) under accelerated ageing condition. Because the life time of these compounds are generally too long to wait for a verdict on their behaviour in use. The ageing results show that mechanical properties follow the same trend as pre-ageing stage.