Mike, you're confused the LectraSan/ElectroScan, PuraSan and other USCG certified Type I MSDs with the original Raritan
Crown Head (which is what had to be in your pre-1980 boats), and which, unlike real Type I and II MSDs, IS a toilet.
The Crown Head was one of the very first macerating electric
toilets...it also had/has a chemical reservoir that shot little chemical (Raritan Concentrate) at the flush as it went down the discharge line on its way to the thru-hull....and because it did macerate and knock down bacteria at least a little, the CG issued a waiver allowing it to be used in lieu of a real treatment device for a few years. But once all the marine
sanitation regs were in place in the CFR, which happened in the early '80s, that waiver was withdrawn. But the Crown Head wasn't the only device that the CG allowed to be used in lieu of a tank or a treatment device...Wilcox Crittenden and Danforth (yes, the anchor
Danforth company) had "macerator chlorinators" that could be used with any toilet. Those ceased to be approved at the same time the Crown Head lost
That waiver has caused a lot of consternation among boat owners on non-navigable inland lakes, all of which are "no discharge" under federal law. However, 40 CFR 140.3 has a clause in it that "grandfathers" any REAL Type I or II installed on a boat built before 1980, on which the device was also installed before 1980, allowing it to be used in lieu of a tank for "the life of the device"...iow, as long as it can be kept working. There are a whole BUNCH of old farts who own boats built before 1980 that also have pre-1980 Crown Heads on 'em who were convinced their boats were "grandfathered"...and some of 'em STILL do!
Today's Type I MSDs aren't toilets...they're devices into which the toilet flushes, where waste is treated and discharged overboard
. Mfrs must submit a prototype to a USCG approved lab, where it's tested...the results then sent to the CG with a recommendation to certify or not. And each device must be recertified every 5 years. The whole certification
process is spelled out in 33 CFR 159.11-19 if you want to read it.
The devices on your pre 1980 boats wouldn't be considered legal
treatment devices anywhere in the US, even in waters where the discharge of treated waste is legal... but you wouldn't be able to use a modern Type I in most of the waters of MA, nor in any RI or CT waters, because they've been designated "no discharge"...making holding tanks
the only legal option. However, the discharge of treated waste from a CG certified Type I or II device IS legal in 95% of coastal waters between New England
the FL Keys. You might want to see what's out there today...and how the various devices work. Raritan Waste Treatment