When Pete is showing MacGyver and Nikki the safe with the diamonds, he puts his ID card into the reader and the number 919747 appears on the screen. When he pulls his card out, the number changes to 841969.
When first opens the vault to store the diamond he is "buying" from Nikkie, the code to open the door is 919747. Later when MacGyver breaks into the vault with Nikki and Amir, the code he uses is 936167.
Rakes generally do not have screw-threaded handles like a broom; they have a tapered metal ferule that fits over a tapered end on the wooden handle, and attaches with hot-hammered rivets, not screw-threads.
Threads made in wood have to be fairly "coarse" to avoid splintering, so even if the rake had threads to attach its head and handle together, like a broom does, the threads would not be nearly so "fine" as a garden hose has; Mac could not have attached them together just by screwing them into each other.
Near then end, Macgyver covers his mouth with a handkerchief to avoid breathing in a gas leaking from a pressurized cylinder. A cloth will only filter out particles, not gas molecules. The gas will still be breathed in.