Ventilation facilities could easily be destroyed by gas explosion in a coal mine and usually lead to the cascade collapse of the entire ventilation system. Altering the ventilation facilities could increase the value of the overpressure peak and the propagation speed of the shock waves. The attenuation law for blast waves in restricted roadway networks was analysed. and calculation mo... https://mysocialfeeder.com/story4381580/posi%C3%A7%C3%B5es-verticalizadas-no-parto-e-a-preven%C3%A7%C3%A3o-de-lacera%C3%A7%C3%B5es-perineais-revis%C3%A3o-sistem%C3%A1tica-e-metan%C3%A1lise