Final answer:
Pacemakers must be removed before cremation to prevent the risk of explosion, which poses a safety threat to crematorium facilities and personnel.
Step-by-step explanation:
A pacemaker must be removed prior to cremation primarily due to the risk of explosion. Pacemakers contain a battery that can generate an intense heat when exposed to the high temperatures of a crematorium. This intense heat can cause the device to explode, posing a safety risk to the crematorium facilities and personnel. Furthermore, the explosion can damage the cremation equipment and cause delays in operations. Therefore, for safety reasons, pacemakers and other biomedical devices with batteries should be removed before the cremation process.