Characterization of the artisanal stone crushing activity in the informal sector in the collines department in benin

The artisanal stone crushing activity, which has grown in recent years, has multiple risk factors. Les Collines, a department of 3 health zones, located between parallels 7 ° and 8 ° 45 north latitude, over 13,931 km2, is a peneplain area composed mainly of granite rocks whose gravel is in great demand in construction. A documentary review was associated with data collection in the field combining observations and interviews on 5 sites in the communes of Savalou, Dassa-Zoumé and Glazoué. The sample size was obtained by the homogeneous exposure group (GHE) technique. The stone crushing activity includes several stages: removal of the bedrock by pyro-diaclasage on the hill, fragmentation in 2 or 3 phases, reduction to gravel, loading and transport. The tools used are manual, mainly hammers, but also iron bars, shovels, hoes, cutters, metal hoops and used tires with large diameter. Pieces of stone serve as a seat and an anvil. The dominant posture is sitting with bent legs framing the anvil. The work is done mainly in the sun; there are some precarious shelters. The activity is made up of repetitive movements, intense physical efforts, awkward postures, often beyond 10 hours a day, long working times in an atmosphere of heat, complex deafening noises and significant manual vibrations. with exposure to pointed and sharp projectiles and mineral dust. This characterization highlights in addition to the traumatic risk, the risk of musculoskeletal disorders and the cardio-respiratory risk, the major risk to be feared being landslide.