Standard precautions can prevent transmission of micro-organisms. This study investigated hand hygiene, handling of needles and use of personal protective equipment in an Indonesian teaching hospital, and performed a multi-faceted intervention study to improve compliance. An intervention was performed in an internal medicine ward and a paediatric ward, consisting of development of a protocol for standard precautions, installation of washstands, educational activities and performance feedback. Before, during and after the intervention, observers monitored compliance with hand hygiene, safe handling of needles and use of gloves, gowns and masks. A gynaecology ward served as the control. Unobtrusive observations were performed to check for an influence of the observers on the overt observations. In total, 7,160 activities were observed. Compliance with hand hygiene increased from 46% to 77% in the internal medicine ward and from 22% to 62% in the paediatric ward. Before the intervention, no safe recapping of needles was recorded in either ward. After the intervention, 20% of needles were recapped safely. Inappropriate gown use decreased in the internal medicine ward. There were no significant changes in use of gloves and masks. There may have been an effect of the overt observations in the paediatric ward, but there was no effect in the internal medicine ward. There were no significant changes in the control ward, except for a decrease in the use of gloves. In conclusion, compliance with hand hygiene procedures improved significantly due to an intervention project focused on education and improved facilities. Compliance with safe handling of needles improved slightly due to introduction of the one-handed method for safe recapping of used needles.