This work reports the results obtained from the comparison involving 7 laboratories in Brazil. This exercise is about the calibration service of surface contamination monitors. The monitor has been calibrated to BS ISO 7503-3, the calibration factor in terms of surface emission rate. The comparison was conducted by the Brazilian National Laboratory of Ionizing Radiation Metrology (LNMRI / IRD) from October 2018 to July 2019. The extensive sources used were 14C, 137Cs, 60Co, 90Sr/90Y, 36Cl and 241Am. The result of this proficiency test was excellent and proved the calibration capacity of the Brazilian network in the calibration service for surface contamination monitors.