It was in the 1980s that USBM published one of the first regulations to protect buildings from the effects of vibrations caused by mine blasting. Several countries have made their own regulations or recommendations since then with vibration limits that are often lower. However, in many places, operators choose vibration limits that are lower than those of existing standards, in order to limit the number of complaints received. The real question is how can we know what level of vibration is likely to create or worsen an existing crack in a construction. MCM, in northern Quebec, is working in a warehouse on the outskirts of the city of Malartic. Within the scope of its environmental monitoring program, together with the joint monitoring committee, MCM has equipped four sample houses for more than 18 months, to know if there is a relationship between the evolution of damage to existing buildings and seismic levels of vibrations created by the blasting of the mine. The publication presents the results of this unique study that has analyzed millions of measurements (seismic, extensometric and temperature) to define what relationship exists between vibration levels and the movement of cracks. Some surprising results compared to some previously published (see ref) could change our perception of the subject.