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Understanding The Cremation Process


Cremation fire blazing

Cremation fire blazing


Cremation is the use of high-temperature burning, vaporization, and oxidation to reduce dead animal or human bodies, to basic chemical compounds, such as gases and mineral fragments retaining the appearance of dry bone



A cremator is an industrial furnace that is able to generate temperatures of 870–980 °C (1600–1800 °F) to ensure disintegration of the corpse. A crematorium may be part of a chapel or a funeral home or may be an independent facility or a service offered by a cemetery. ( In the case where I work it's part of a chapel and also a cemetery too)

The chamber where the body is placed is called a retort and is lined with heat-resistant refractory bricks. Refractory bricks are designed in several layers. The outermost layer is usually simply an insulation material, e.g., mineral wool. Inside is typically a layer of insulation brick, mostly calcium silicate in nature. Heavy duty cremators are usually designed with two layers of fire bricks inside the insulation layer. The layer of fire bricks in contact with the combustion process protects the outer layer and is required to be replaced from time to time. The coffin or container is inserted into the retort as quickly as possible to avoid heat loss through the top door.



In the United States federal law does not dictate any container requirements for cremation. Certain states however may require an opaque or non-transparent container of all cremations. This can be a simple corrugated-cardboard box or a wooden casket (coffin). Most casket manufacturers provide lines of caskets that are specially built for cremation.Another option is a cardboard box that fits inside a wooden shell, which is designed to look like a traditional casket. After the funeral service, the box is removed from the shell before cremation, permitting the shell to be re-used. Funeral homes may also offer rental caskets, which are traditional caskets used only during the services, after which the bodies are transferred to other containers for cremation. Rental caskets are sometimes designed with removable beds and liners, which are replaced after each use.

The photo used for this post is a picture of the cremation container that we use. They start off as flat boxes and are put together when needed... which I do sometimes



Depending on the container ( casket or cardboard box) It takes an average of 3-5 hours for the cremation to be completed. Then after the chamber is opened and has to cool down for about an hour before the remains can be collected in a collection tray. This is done with a big broom or brush as shown here.



Contrary to popular belief... even before I worked here this is what I thought... only one person goes in the retort at a time. They are kept track of when they come in by a tag system. The names are written in a book and given a number which then corresponds with a metal tag that has the same number and is put in the retort with the body. The tag does not burn and stays with the cremains at all times.



When the cremated remains come out of the retort they look like this. Everything burns away except for the bones, also if you have any artificial body a knee or a hip...rods or pins anywhere..etc. They do not burn and are collected in a recycling bin, when the bin is full it is sent to a recycling center. Unless the family specifically asks for the part back..which they sometimes do..although I can't imagne what they would do with it.

This picture is not from our facility but this is what the remains look like...they do not burn into ashes...another common misconception



The bone fragments are then combed through with a big magnet to remove any metal we may have missed, staples from surgeries.. parts of the casket...etc. They are then put in a grinder, which is much like a big food processor or blender, and are ground into the " ASHES" which is what the family gets back.

This is a picture of our grinder... everything is cleaned out before the next person so there is also no mixing of people.. I know that sounds weird.. but you wouldn't want some part of a stranger mixed in with your loved one... also I know this is not technical but I think it's better for me to describe it in an understandable way rather than the technical jargon the articles were using.




This is what you end up with when it's all said and done. The round metal tag is the one that stays with the person from start to finish. In fact one time someone found a box with cremains like this in a park and we were able to trace back who it was and what funeral home it came from by using the number on the tag.

Also something interesting. How big the person is doesn't have anything to do with the amount of ashes. It's the person's bone structure. So you can cremate a 500 lb person who is short and a 100 pound person who is tall...and there will be more ashes from the 100 lb person than the 500 lb one.



After this there is an infinite number of things the family can do with the ashes. Other than just putting them in an urn on their mantel. Some people bury them. you can have some of the ashes put in special necklace charms or bracelets and wear them. You can put them in small keep sake urns and give a little to everyone in the family. Usually the funeral director will sell you the urn or whatever you will be putting them in. At our facility , if the funeral director doesn't request a certain urn, they are packaged in cardboard boxes with a permit ( which I type up from other paperwork that I get) and given to the funeral director. We do not deal directly with the family ever. You have to go through a funeral director to have a cremation done.

the picture is a selection of the urns we sell..but there are catalogs with hundreds of different ones and also you can buy them yourself on line. The cardboard boxes on the table are waiting to be picked up



Here we have what's called an in-door Columbarium. Which is a room with niches that you can put your urn in to display it but also not have to have it in your house. The benefit of this is you can come and visit no matter what the weather is since it's inside... all year long.

In the picture above on the left is the original columbarium room, we are just about out of space in there so this past december we added another wall of niches. In both rooms there are places to sit and it's quiet if you want to sit and reflect or pray...etc

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These are our outdoor Columbarium niches. Behind each of the marble panels there are 2 spaces to fit an urn. This type of memorialization is good when you don't want your loved one interred in the ground but still want to be able to visit them whenever you'd like. The outdoor Columbarium is available no matter what time or day you wish to visit



There is much more I can write on this subject, but I just wanted to give the reader a gist of how cremation is done. As for me personally I am choosing cremation. The place where I work is also a cemetery. To me the process and end results of cremation are much cleaner and humane than being left to decompose in the ground for 20 years. However, the choice is yours. Thank you for reading !!


This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.


Marinda Seiwell (author) from Pennsylvania on September 27, 2016:

Zachary, So sorry to hear about your Mother :( I'm glad you were able to feel a little better after reading about the cremation process ! God Bless you and your Family !

Zachary Green on April 29, 2016:

I just want to say thank you. My mother passed last week and we decided to have her cremated. And well I was use to the traditional funeral, casket, and cemetery but this has really helped kinda bring some closure that I guess I have been looking for since her service.

Marinda Seiwell (author) from Pennsylvania on February 12, 2016:

Jack Hagan, Cremation is a very personal choice. Some nationalities as well as different religions forbid being cremated. Thank you for the kind words about my Hub... it was my intention to inform people on the process so I am happy to hear I've done that :)

Marinda Seiwell (author) from Pennsylvania on February 12, 2016:

Baylie, I'm not familiar with the cremation process for pets. Although I suspect the cremation aspect itself is probably the same, I'm sure the procedures are different than with a human body. I have 2 cats and that is something for me to think about when their time comes. Thank you for your comment :)

Jack Hagan from New York on July 15, 2015:

I don't prefer the cremation process over burial because I think it is more environment friendly idea and I don't wish to be burned after my death. However, I admit that this guide is very informative and by the help of these instructive facts, people can easily learn the details about the cremation process.

Baylie on June 01, 2015:

It depends on how your vet hdenlas the bodies. Call as soon as possible to find out. If you want your cat's ashes back, you will probably have to pay extra, and the ashes may be given back to your in just a cardboard box. However, many vets these days, if the pet's owners haven't given any other instruction as to what to do with the body, sell the bodies to rendering plants where sometimes they are skinned (and the pelts sold to other places) and the bodes are just thrown into acid vats. Or the bodes are sold to labs for vet school use. And probably other things I don't really want to think about. So get ahold of your vet as soon as possible and hope he hasn't already sent the body off.

Marinda Seiwell (author) from Pennsylvania on April 14, 2015:

Thank you Lee ! I feel the same way as you. Also I work in a cemetery and have heard horror stories of people being exhumed to be moved to different cemeteries YEARS after they have 15 years later...and they are a pile of goo and bones and hair and smelly.. YUCK. I definitely don't want to linger that long after death !

Lee Cloak on April 14, 2015:

Very good hub, great information, I have always wondered about the process, I think its for me, I Don't fancy waking up in a coffin six feet under I read story's, thanks , voted up, Lee

Marinda Seiwell (author) from Pennsylvania on March 21, 2015:

Thank you very much Rachel!!

Rachel L Alba from Every Day Cooking and Baking on March 21, 2015:

A very well written and informative hub. I'm sure it will allow other people decide what they would like to do for themselves or their loved ones. I voted up, useful and interesting and 5 stars.

Blessings to you.

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