So today a burned-out 4-foot flourescent tube bulb exploded on my kitchen floor.

[Liberty Belle]

1. Here are guidelines for how to clean up a broken flourescent bulb:

https://www.hazwastehelp.org/mercury/broken.aspx

How to clean up a broken fluorescent bulb or tube

Compact fluorescent light bulbs (CFLs) and tubes save energy and are safe to use but they contain mercury. If you break one, follow these instructions to safely clean it up before you recycle or safely dispose of the waste.
Do not sweep it. Do not vacuum.
How to clean up a broken compact fluorescent light bulb or tube from hard surfaces such as a tile floor or countertop

Have people and pets leave the room. DO NOT let anyone walk through the breakage area on their way out.
Open windows and shut off central forced-air heating/cooling system if you have one then leave the room to vent vapors for at least 15 minutes.
Remove jewelry and put on rubber gloves.
Use stiff paper or cardboard to pick up large pieces.
Place them in a secure closed container, preferably a glass jar with a metal screw top lid and seal like a canning jar. This type of container works best to contain the mercury vapors.
Use index cards or playing cards to pick up small pieces and powder.
Use sticky tape, such as duct tape or masking tape to pick up fine particles.
Wipe the area clean with a damp paper towel or wet wipe.
Place all materials used to clean-up into a sealed container, preferably glass.
Continue ventilating the room for several hours.
If clothing, bedding or other soft materials have come in direct contact with broken glass or mercury powder, they should be taken to your local household hazardous waste facility. DO NOT wash in washing machine, sink or by other methods. Place soft materials in a sealed plastic bag.
If shoes come into direct contact with broken glass or mercury powder, DO NOT spread mercury over a larger area. Wipe shoes with a damp paper towel or wet wipe and place towel or wipe into a sealed container, preferably glass.
Immediately place all clean-up materials in a protected area away from children and pets.
Wash your hands.
Dispose of cleaning supplies, broken bulbs and tubes and clothing, bedding or other soft materials at your local household hazardous waste facility – not in your garbage.


How to clean up a broken compact fluorescent light bulb or tube from carpet.

Follow the same instructions as for cleaning-up on a hard surface.

Consider removing and disposing of throw rugs or the area of carpet where the breakage occurred as a precaution, particularly if the rug is in an area frequented by infants, small children or pregnant women.
If the carpet is not removed, shut off central forced air heating/cooling system and open the window to the room during the next several times you vacuum the carpet to provide good ventilation. Remove the vacuum bag and put the bag in a sealed plastic bag outside of the house. Take the sealed plastic bag to a household hazardous waste facility for disposal.
How to clean up a broken fluorescent bulb or tube

Compact fluorescent light bulbs (CFLs) and tubes save energy and are safe to use but they contain mercury. If you break one, follow these instructions to safely clean it up before you recycle or safely dispose of the waste.
Do not sweep it. Do not vacuum.
How to clean up a broken compact fluorescent light bulb or tube from hard surfaces such as a tile floor or countertop

Have people and pets leave the room. DO NOT let anyone walk through the breakage area on their way out.
Open windows and shut off central forced-air heating/cooling system if you have one then leave the room to vent vapors for at least 15 minutes.
Remove jewelry and put on rubber gloves.
Use stiff paper or cardboard to pick up large pieces.
Place them in a secure closed container, preferably a glass jar with a metal screw top lid and seal like a canning jar. This type of container works best to contain the mercury vapors.
Use index cards or playing cards to pick up small pieces and powder.
Use sticky tape, such as duct tape or masking tape to pick up fine particles.
Wipe the area clean with a damp paper towel or wet wipe.
Place all materials used to clean-up into a sealed container, preferably glass.
Continue ventilating the room for several hours.
If clothing, bedding or other soft materials have come in direct contact with broken glass or mercury powder, they should be taken to your local household hazardous waste facility. DO NOT wash in washing machine, sink or by other methods. Place soft materials in a sealed plastic bag.
If shoes come into direct contact with broken glass or mercury powder, DO NOT spread mercury over a larger area. Wipe shoes with a damp paper towel or wet wipe and place towel or wipe into a sealed container, preferably glass.
Immediately place all clean-up materials in a protected area away from children and pets.
Wash your hands.
Dispose of cleaning supplies, broken bulbs and tubes and clothing, bedding or other soft materials at your local household hazardous waste facility – not in your garbage.


How to clean up a broken compact fluorescent light bulb or tube from carpet.

Follow the same instructions as for cleaning-up on a hard surface.

Consider removing and disposing of throw rugs or the area of carpet where the breakage occurred as a precaution, particularly if the rug is in an area frequented by infants, small children or pregnant women.
If the carpet is not removed, shut off central forced air heating/cooling system and open the window to the room during the next several times you vacuum the carpet to provide good ventilation. Remove the vacuum bag and put the bag in a sealed plastic bag outside of the house. Take the sealed plastic bag to a household hazardous waste facility for disposal.


(Note: After realizing the hazards of compact mercury fluorescent bulbs a few years ago, I got rid of them all. Not worth the health risks in my view, but since yours broke on a hard surface and you did take reasonable steps you'll probably be fine.