These look familiar; I've long known about such things from reading newspapers and magazines, rare bouts of watching TV news and occasionally being "hypnotized" by the always lurid prison porn that is shown, usually late at night, on MSNBC, usually the most interesting thing that that cable channel runs on air.
A couple of the shivs look like they might be constructed of "starched" cardboard. Is that correct? If only those benighted sociopaths would apply just some of their energy and resourcefulness to honest work, we'd have a very little better economy, and they'd be a lot happier themselves. Too bad.
Many years ago, I covered a prison riot for Time magazine at Jackson Prison in Michigan. Scary places, those maximum security lock-ups. I hope you don't have to be too involved with the population in your work. It will be a lot better for your mental health if this was the last time you had to go inside the walls.
As far as photography and Canon goes, well, I'm kind of glad I didn't get the point. 
Regards,
David
Yeas, Dear Friend dafrank.
Yes " the shivs look like they might be constructed of "starched" cardboard ", after dry, and re starched 4-5 times = the good sharp knife, after sharp with concrete floor slab's rough texture.
They( the Inmates), have 24 hours per day, 7 days a week, and 52 weeks per years to imagination and invent the SHIVE / weapon from every thing in front of them. I ask the Inmates " Why"---They say the same thing = to protect them self from another inmate from Rape and Beating Them at the Exercise Yard. No, They,the inmates will not harm the Jailers or the Guards, Because they can get Kill by the Special Security guard with the real GUN, Incase of the Guards/ Jailers injure , or move to another Jail Facility, where are worst than my Jail.
Yes, The Jails that I design with a great Restaurant Grade Kitchen, where will provide 3 Great Meals per NS. State Laws( Beef, Pork or Chicken for Lunch and Dinner as your Choice ), 2 Hours out door Exercise in every 7 days, Health care, Denture care with Doctors/ Nurses, Library that they can check out the Book to read and study--- 14 hours of Cable TV.---1 Hour per week of Relative Visitation---- No one want to leave from my Jail----Ha, Ha, Ha.
Yes, When I work in Jails, I must have 2 Big Guards/ Jailers stand behind my back all the times, Yes, I can fight with 2 Inmate, But not 3 or 5 ( With SHIVS) at the same time---No, I am not Bruce Lee----Ha, Ha, Ha.
Good night.
Surapon