Freida Carson wrote a wonderful publication about Bis CME many years ago,
and not only is hydrochloric acid a problem but also nitric and some other
acids.  Apparently formation of this chemical occurs with strong mineral
acids.  

I always took it to heart that mixing formalin and HCl were a no no, and
rinse bone specimens before immersion in HCl mixtures.  It is everyone's
best interest to use a chemical fume hood when dealing with formalin then
hydrochloric acid or any other acid - when dispensing stock or ready made
solutions, making up, and/or using any of these solutions.  The acids very
corrosive, toxic, and nasty to breathe - formic and HCl, nitric are
horrible.  As for drain dumping, neutralizing the acids is probably a good
idea, and whether or not you can drain dump formalin per local water
treatment plant regulations is something one need to look into.     

Actually, a combination fixation/decalcifier mixture (strong mineral
acidand formalin is NEVER used in this lab, in fact would not even buy them
per reference to Bis CME formation.  We prefer to fix, rinse briefly, and
then decalcify the bone - always inside a hood. 

As for the proprietaary word "decal", you can always use D'cal to
circumvent, we went through this years ago on Histonet.    
Gayle Callis
MT,HT,HTL(ASCP)
Histopathology Supervisor
Veterinary Molecular Biology - Marsh Lab
Montana State University - Bozeman
19th and Lincoln St
Bozeman MT 59717-3610

406 994-6367
406 994-4303 (FAX)