They produced a database documenting the task, the tools used, the occupation, the degree of confinement of the premises, the construction sector, the purpose or reason for the construction site, the exposure control methods, and the sampling and analysis techniques. [...] The occupation titles were coded from the list of occupations in the Regulation respecting the vocational training of the workforce in the construction industry [35] and the occupations described in the most recent collective agreements for the Québec construction industry (Civil IRSST -. Construction Workers' Exposure to Crystalline Silica 7 Literature Review and Analysis Engineering and Roadwork [...] The efficiency is reported as a percentage in relation to the concentration of dust observed in the absence of control methods and in terms of the capacity of these methods to reduce the exposure below the threshold limit values (TLV) applicable in the jurisdictions involved. [...] IRSST -. Construction Workers' Exposure to Crystalline Silica 15 Literature Review and Analysis All of the statistical parameters retained to describe the distribution of the measurements are presented in tables in Appendices 4 to 9. This completes the information presented in the graphs and shows the data dispersion including the extreme values in the distribution. [...] Nature of the sampling site Comparison of the geometric means of the exposure levels associated with each of the values of the “Nature of the sampling site” parameter does not confirm the intuitive assumption that these levels should progressively decrease when going from an enclosed space to a completely open outdoor environment.