Remember, we are talking about an incinerator that reaches temperatures over 1600 degrees F – to say there is no risk of fire is insane. I have included links below to news reports of several crematories that have caught fire.
Arkansas addresses fire safety in their laws
(I) Sanitation and Fire Safety
(1) The Crematory, Cremation Chamber, and all related buildings and equipment shall be maintained in a clean and sanitary manner. All equipment in and related to the Crematory shall be maintained in good condition according to the directions given by the manufacturer of the equipment and the appropriate regulatory authorities.
(2) Crematory Authorities applying for licensure after the promulgation of these rules shall construct their crematory in such a manner as to meet the following minimum standards:
a. The floor of the crematory shall be of concrete and not covered with a flammable material.
b. The walls and ceiling of the Crematory shall be of fireproof and/or fire retardant materials.
c. The Crematory shall have adequate ventilation and adequate entrances and exits for the protection of the public and Authority personnel.
(3) No flammable material shall be stored within five feet of the cremation chamber.
So, I think it is not an invalid concern.