Nine lives were lost in separate incidents in just 12 weeks between June 2012 and September 2012. Half of the deaths occurred in skip hire and waste transfer premises.
HSE operations director Heather Bryant, who leads the HSE's waste and recycling strategy, said: "These fatal accidents should be a stark reminder for all employers in this sector to check their controls on use of vehicles and equipment, and to make sure that staff are properly trained and supervised.
"We will not hesitate to take action if we find evidence that lives are being put at risk.
"There is no room for complacency in this sector - close attention must be given to equipment like compactors and skip vehicles."
HSE investigations into the nine fatalities are continuing.