What do they mean by Mass for the Hearing Impaired?

Do you ever see that on some  Catholic church websites? I do.  Check it out for yourself.  It makes me scratch my head.  What does that mean?

Does it mean the Mass is accessible to the hearing impaired?  Who are the hearing impaired?   When I check it out, I often only find ASL.  Is
a Mass in ASL, a Mass for the hearing impaired?

Indeed the mainstream often think all the deaf and hard of hearing use sign language when the diversity is not explained further.  You can find many church websites saying something to the effect 'Mass for the Hearing Impaired' only to find out it only offers sign language, while totally necessary, it does not provide access to the majority of the 'hearing impaired'. Both Captioning, Sign language, and Audio loops are very effective communication access that can provide 'Sacrosanctum Concilium'  for the diverse deaf and hard of hearing population.

"Only a small percentage of those who are deaf, deafened, and hard of hearing communicate through American Sign Language. Providing CART services can help overcome this barrier.

ASL is a form of language, and many people who communicate through ASL may not have the reading comprehension or speed necessary to utilize CART. However, many individuals who are deaf, deafened, and hard of hearing, especially late-deafened adults and those who lost their hearing after learning speech, read lips and rely solely on CART and captioning in group settings. There is not a one-size-fits-all solution when dealing with communication access. Consumers need access to the accommodation that best meets their individual needs. “ 

(Source:  http://alacarteconnection.com/how-works/