References: Wikipedia: http://en.wikipedia.org/wiki/Cremation
At a crematorium, the body, lying in a coffin, is placed in a cremator.
A cremator is an industrial furnace that generates enough heat to burn a body to ashes.
Typical heat: 760 - 1150 degrees Celsius (1400 - 2100 degrees Fahrenheit).
The intense heat can cause any implanted battery - in a pacemaker or defibrillator - to explode in the cremator.
A certification process must identify any at-risk batteries and ensure that they are removed before cremation.
Human bodies are made up of a high proportion of water - this vaporises in the furnace.
Most of the solid tissue is vaporised and/or combusted in the intense heat. The resulting gases are released into the atmosphere.
The cremation process takes approximately 1.5 to 2 hours to complete.
At the end of the process there is some residual matter, including ash and fragments of bone, weighing approximately 1.5 - 3 kg.
Once these remains have cooled sufficiently, a special grinding process (in a cremulator) reduces the fragments to a fine ash, similar in texture and colour to sand. These ashes are returned to the family.
Surgical implants such as artificial joints, dental implants, fillings are safe to go into a cremator so long as there is no battery.
Titanium implants do not melt even at the high temperatures in a cremator: these are removed after the cremation process and can be disposed of separately.
A "leadless" pacemaker is a new category of battery-powered devices.
- It has no wires or leads that connect the device (in the heart) to a battery that is implanted in the body (usually the chest wall).
- Leadless pacemakers have a tiny battery that is self-contained in a device that is the size and shape of a medication capsule.
- Leadless pacemaker units are entirely embedded in the heart muscle and cannot readily be removed.
- The batteries in leadless pacemakers are so small that they are safe to be cremated.