HazMat Prinnies, according to their accounts, were hired through the Netherworld Shopping Channel and then trained by their original boss to deal with hazardous material spills.
Given an overenthusiastic order to clean the Ten'ou Haus living room to Class 4 standards they proceeded to get the room to those standards. In the process, rei.bot took over their direction and assigned them to get the entire house to the same standards.
The HazMat Prinnies have enthusiastically attacked the job and may be seen in any part of the house in their bright yellow HazMat suits. They have been so enthusiastic that they managed to get Haruka's room to a state of clean (if not to their Class 4 goal yet), and keep it there with daily decon duties.
There are roughly 100 prinnies in the group:
- Eight Groups of 10 (These prinnies run on a rotating series of three hour shifts of Primary, Secondary, and Backup, such that any one squad works a total nine hours a day and the house is covered 24/7.):
- HazMat Prinny Squad Alpha
- HazMat Prinny Squad Bravo
- HazMat Prinny Squad Charlie
- HazMat Prinny Squad Delta
- HazMat Prinny Squad Echo
- HazMat Prinny Squad Foxtrot
- HazMat Prinny Squad Golf
- HazMat Prinny Squad Hotel
- 20 prinny HQ Group:
- HazMat Prinny Engineers (10)
- HazMat Prinny Document Control & Contracts(5)
- HazMat Prinny Project Control & Finance (2)
- HazMat Prinny Lieutenant (2)
- HazMat Prinny Captain (1)
They have taken the initiative to fit the whole house ventilation system with HEPA filters in every room, and they pass the air system through a rather advanced air purifier. While they are constantly cleaning, it is primarily with vacuum-cleaners and dust-collectors. They typically save the Bleach and Hydrogen Peroxide for "biological spills," although they make sure the bathrooms are very clean... especially when Haruka has been using them.
There is at least one Prinny, called The Quartermaster (he wears Steel Rimmed Glasses), who has designed most of their mecha and special weapons.