Toilet Design Specifications
The specifications listed below represent the maximum allowed values. Proposed designs should at least meet them and will preferentially be lower than them. The toilet design should:
- Function in both microgravity and lunar gravity
- Have a mass of less than 15 Kg in Earth’s gravity
- Occupy a volume no greater than 0.12 m3 (4.24 ft3)
- Consume less than 70 Watts of power
- Operate with a noise level less than 60 decibels (no louder than an average bathroom fan)
- Accommodate both female and male users
- Accommodate users ranging from 58 to 77 inches tall and 107 to 290 lbs in weight
Toilet Performance Specifications
We are looking for a design that captures all the functionality of a toilet on Earth. At a minimum, crew using lunar toilets should not be exposed to vacuum during use, and toilet designs should be able to:
- Accommodate simultaneous urination and defecation
- Collect up to 1 liter of urine per use, with an average of 6 uses per crew per day
- Accommodate 500g of fecal matter per defecation, with an average of 2 uses per crew per day
- Accommodate 500g of diarrhea per event
- Accommodate an average of 114g of female menses, per crew per day
- Stabilize urine to avoid the generation of gas and particulates
- Accommodate crew use of toilet hygiene products, like toilet paper, wipes, and gloves
- Be clear of previous user’s urine and feces in preparation for the next use
- Allow for transfer of collected waste to storage and/or provide for external vehicle disposal. Minimal Lander volume requires regularly minimizing waste storage or removing it from the vehicle
- Allow for easy cleaning and maintenance, with 5 minute turnaround time or less between uses
Additionally, in the event of a system failure, the toilet designs will ensure that:- All waste materials collected remain safely stored
- The crew is not exposed to urine, feces, or other collected materials
- The crew is not exposed to vacuum