Who uses American Sign Language and who doesn't
          among the deaf and hard of hearing ?

"Counting the number of ASL speakers is difficult because ASL users have never been counted by the American census.[1]:1[nb 4] The ultimate source for current estimates of the number of ASL users in the United States is a report for the National Census of the Deaf Population (NCDP) by Schein and Delk (1974).[1]:17 Based on a 1972 survey of the NCDP, Schein and Delk provided estimates consistent with a signing population between 250,000 and 500,000.[1]:26 The survey did not distinguish between ASL and other forms of signing; in fact, the name "ASL" was not yet in widespread use.[1]:18Incorrect figures are sometimes cited for the population of ASL speakers in the United States based on misunderstandings of known statistics.[1]:20 Demographics of the deaf population have been confused with those of ASL use, since adults who become deaf late in life rarely use ASL in the home.[1]:21 This accounts for currently cited estimations which are greater than 500,000; such mistaken estimations can reach as high as 15,000,000.[1]:1, 21 A 100,000-person lower bound has been cited for ASL users; the source of this figure is unclear, but it may be an estimate of prelingual deafness, which is correlated with but not equivalent to signing.[1]:22ASL is sometimes incorrectly cited as the third- or fourth-most-spoken language in the United States.[1]:15, 22 These figures misquote Schein and Delk (1974), who actually concluded that ASL speakers constituted the third-largest population requiring an interpreter in court.[1]:15, 22 Although this would make ASL the third-most used language among monolinguals other than English, it does not imply that it is the fourth-most-spoken language in the United States, since speakers of other languages may also speak English.[1]:21–22”

Above taken from Wikipedia/Web source.

However Sign Language is the 4th most studied language (which is not saying same the same thing as ‘user population’):http://usatoday30.usatoday.com/news/education/2010-12-08-1Alanguages08_ST_N.htm

How many people use American Sign Language? 500,000 according to this source at https://research.gallaudet.edu/Presentations/2004-04-07-1.pdf and also http://research.gallaudet.edu/Publications/ASL_Users.pdf

"Fourth most used language" confusion versus "Fourth most studied language" (which is not saying the same thing):  See http://libguides.gallaudet.edu/content.php?pid=114804&sid=991835  (estimated 500,000 up to 2 million ASL users is this web source link)

3% of the Hearing loss population uses sign language as PRIMARY Language (native) at :  http://www.nchearingloss.org/article_demographics.htm

While this data is almost 10 years old and hearing loss demographics have sky rocketed to 48 million now (and counting) with aging baby boomers driving up the demographics,  it does give you an idea of hearing loss:

 "  In a Better Hearing Institute survey published in 2005, 31 million people are currently estimated to suffer from hearing loss. Of those 31 million, 29 million people are hard of hearing and 2 million are deaf. And of those 2 million, 1.5 million are late-deafened (deafened after the acquisition of spoken language)…" (Source:  http://healthbridges.info/?p=333)  These people generally do not know sign language and can benefit from CART or real time captioning

"Out of 100 people, 10 have a significant hearing problem. Of those 10 people, one or two use sign language. The rest do not now sign language.” Source:  http://captioningtheword.com/information.html)

In the research here on how many deaf/HOH: http://research.gallaudet.edu/Demographics/factsheet.php/deaf-US.php#Q1 

The reference is  to deaf in audiogram concepts, not culture and linguistic concepts.  Just saying one can't hear or understand speech or deaf in both ears doesn't mean the person uses sign language.

 They may or may not because the research is based on audiogram perceptions.   This includes those with severe and profound hearing loss, late deaf and oral deaf as well as culturally deaf because the stats do not define cultural and linguistic preferences.

In other words, it only tells you who could be deaf but it doesn't tell you who uses sign language.

On the other hand, there are many hard of hearing people who are 'Deaf' as a cultural and linguistic worldview even though their audiograms reflect mild and moderate  hearing loss.  If one wants to research the number of 'Deaf' (culturally speaking, that is those who use sign language) a different research would be needed, one that reflects the language user and not audiogram perceptions.

"The majority of people who are deaf and hard of hearing do not know sign language. According to a Johns Hopkins study, more than 48 million people in the United States are deaf or hard of hearing, or a fifth of all Americans. Of these, almost 99 percent lost their hearing or were raised orally–not using sign language–and rely on their residual hearing (aided by hearing aids or cochlear implants), speech reading, and the printed word for communication access. This group of people are greatly aided by text forms of access." (Source:  http://www.captionaccess.com/communication-access-101/?replytocom=41)

"However, like 98% of the 35 million* deaf and hard of hearing people in the USA, I consider ASL (American Sign Language) a gorgeous language that I can't fluently understand. CART (Communication Access Real time Transcription) offers an alternative option for folks like me;…”(Source: http://opensource.com/life/11/12/open-source-changes-face-stenography-and-possibilities-hearing-impaired)  * note: now 48 million and counting and will double by 2030

"Terminology usage varies. People may refer to themselves as “hard of hearing,” “hearing impaired,” late-deafened,” “deaf,” or may say they have a “hearing loss.” " (Source: http://healthbridges.info/?p=333)

"CART is a type of “accommodation” service for people with disabilities.  In function, CART is similar to sign language interpreting for people who are deaf, because it transforms spoken language into a visual format that is appropriate for people with hearing loss.  But CART can be used by the 95% of hard of hearing and deaf people who do not use American Sign Language (ASL) to communicate." 

(Source: http://www.visiblevoices.com/faq.html

“Statistics show that only 10% of the 24,000,000 deaf and hard-of-hearing people in the United States understand sign language.

The other 90% rely on captioning.” 

(Source: http://www.abercap.com/blog/2008/10/07/sign-language-interpreter-vs-closed-captioning/)

"What does it mean for communication to be “effective”? Simply put, “effective communication” means that whatever is written or spoken must be as clear and understandable to people with disabilities as it is for people who do not have disabilities."

(Source: http://www.ada.gov/pcatoolkit/chap3toolkit.htm)

Effective communication:   http://www.dartmouth.edu/~accessibility/effcomm/index.html

"Accessible meeting space allows

 everyone to participate." 

(Source: http://www.ada.gov/business/accessiblemtg.htm

This is an interesting article how churches could provide better access for the deaf and hard of hearing:  

Losing My Religion? : http://origin.misc.pagesuite.com/pdfdownload/7c11713b-7af4-45b3-86b6-2026d9ce54e4.pdf

Catholics With Hearing Loss Yahoo Forum Group

If you are Catholic with a hearing loss (mild to profound) and  interested in
discussing with others about how to make the Mass and other parts of church
life more accessible, along with supporting one another spiritually  - Subscribe at

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Group Description

Catholics with Hearing loss interested in having the Mass in CC (CART), audio induction loops and other accommodations, along with conferences and workshops and how to support accessibility in the church and one another.