Figure 1 Mean (SD) for Personal Attenuation Rating (PAR). Group size by fit method and protocol are indicated on x-axis. PAR indicates the amount of sound attenuation provided by a hearing protection device (HPD). A larger value indicates greater sound attenuation. Dark gray columns (SELF-Fit) represent results when training recruits fit their own HPDs. Cross-hatch columns represent the PAR results when HPDs were fit by the experimenter (EXP-Fit). Light gray columns show results when training recruits fit their own HPDs following an experimenter fit (SUB Re-Fit). ^*SDs could not be calculated with one recruit and should be viewed with caution with three recruits; means are included to show results for follow-up subjects