A Health Canada warning aimed at health-care facilities says three people have died and nine have been injured since 2009 after becoming trapped in hospital beds.

The warning, issued Monday, says there have been 12 reported incidents of patients getting entangled in beds.

The federal health agency says the warning relates to unprotected side rails and improperly fitted mattresses, as well as beds made before 2000.

Here's the breakdown of the 12 verified incidents of death and injury related to bed entrapment:

• Eight were in nursing homes or long-term-care facilities.
• Three happened in hospitals.
• One incident happened at home.

In one incident, says Health Canada, a patient became trapped in the opening between the split side rails of a Stryker Model FL14E1 long-term-care electric bed. That bed is no longer being manufactured but it's still in use in various facilities.

The agency advises health-care facilities that still use beds made before 2000 to contact manufacturers to get advised on how to reduce entrapment hazards, including using covers to fit over the gaps between rails and ensuring replacement mattresses are the correct size for the bed frame.