Abstract: Taking the practice of mining activities in an underground mine for example,the design of blasting work for pillar drawing and goaf treatment is described.According to the fact that there are usually only few stages of short delay detonators,an inhole outhole combined,relaywise microsecond delay blasting system using short delay detonator,fuse primer and initial firing detonator is developed.In addition,methods for inspecting the safety in blasting work are explained in details.