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Re: Example of accessible CAPTCHAS that work well

From: Sandi Wassmer <sandi@copious.co.uk>
Date: Thu, 17 Nov 2011 19:38:13 +0000
Message-Id: <428A1CCF-2A52-42F2-9E85-AA5B18C2BB2F@copious.co.uk>
Cc: Ginger Claassen <ginger.claassen@gmx.de>, Denis Boudreau <dboudreau@accessibiliteweb.com>, wai-eo-editors <wai-eo-editors@w3.org>, WAI Interest Group <w3c-wai-ig@w3.org>
To: "accessys@smart.net" <accessys@smart.net>
This is an area that we have agonised over in considerable detail, in order to make form completion as effortless as possible for end users, whilst also maintaining site security.

I agree with Denis that Captcha is a resounding No and that SAPTCHA, or Text Captcha as it is commonly referred to, is the better option. 

It is not my place to comment on W3C Policy, but my concern is that ignoring it altogether will give rise to folk seeking guidance in places that may not follow accessibility best practices. If options are presented including their associated areas of concern, this would not be deemed as endorsement:  providing practical examples that keep folk on the path of accessibility has got to be the best bet! 

These are the sort of commercial conundrums we grapple with every day, when accessibility conformance competes with other best practices, client requirements, integration with third party systems and suchlike.  

In using SAPTCHA, developers should give consideration to the areas where accessibility is compromised. 

As SAPTCHA puts demands on the cognitive capabilities of end users, ensuring that questions place the lowest cognitive load possible is essential.  

It is also important to avoid cultural, geographical and other such anomalies. 

It is optimal to have control over SAPTCHA's functionality and not have recourse to third parties if at all possible. 

In order to assist with error prevention, providing a brief explanation as part of the <label>, such as "helps to stop spam", rather than using ambiguous statements such as "are you human?" is also helpful.

Kind regards,


Sent from my iPad

Sandi Wassmer
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On 17 Nov 2011, at 16:27, accessys@smart.net wrote:

> yes one and only one web site I have visited uses a similar system. it asks if fire is 1 hot or  2 cold    very simple question but it works so seamlessly that I had forgotten about it when I posted.
> Bob
> On Thu, 17 Nov 2011, Ginger Claassen wrote:
>> Date: Thu, 17 Nov 2011 17:12:38 +0100
>> From: Ginger Claassen <ginger.claassen@gmx.de>
>> To: accessys@smart.net
>> Cc: Denis Boudreau <dboudreau@accessibiliteweb.com>,
>>    wai-eo-editors <wai-eo-editors@w3.org>,
>>    WAI Interest Group <w3c-wai-ig@w3.org>
>> Subject: Re: Example of accessible CAPTCHAS that work well
>> Resent-Date: Thu, 17 Nov 2011 16:13:22 +0000
>> Resent-From: w3c-wai-ig@w3.org
>> Dear all,
>> Regarding accessible CAPTCHAS I found a very few so far where one has to solve a very simple mathmatical question e.g. How much is 3 + 4?
>> In my opinion that is quite accessible or do I oversee something here?
>> Solong
>>    Ginger
>> On 17.11.2011 16:38, accessys@smart.net wrote:
>>> have to agree, I have yet to find a CAPTCHAS that I have not had trouble
>>> with. and the "accessible" workarounds that some "Claim" to be compliant
>>> are either so clunky or so complex as to be worthless..
>>> more than one site I have used and as soon as I run accross the Captchas
>>> I just close the site and go somewhere else. I understand the purpose of
>>> these things and apparently they are actually being used to help
>>> transcribe documents but they are far more trouble than they are worth.
>>> just my two pence
>>> Bob
>>> On Thu, 17 Nov 2011, Denis Boudreau wrote:
>>>> Date: Thu, 17 Nov 2011 09:53:45 -0500
>>>> From: Denis Boudreau <dboudreau@accessibiliteweb.com>
>>>> To: wai-eo-editors <wai-eo-editors@w3.org>,
>>>> WAI Interest Group <w3c-wai-ig@w3.org>
>>>> Subject: Re: Example of accessible CAPTCHAS that work well
>>>> Resent-Date: Thu, 17 Nov 2011 14:54:19 +0000
>>>> Resent-From: w3c-wai-ig@w3.org
>>>> Hi Phil,
>>>> Don't mean to start a thread here, but in my opinion, there is no such
>>>> thing as a best practice working example of accessible Captcha.
>>>> Except maybe for some (certainly not all) textCaptchas examples, all
>>>> captchas are flawed by design and are always inaccessible for some users.
>>>> Integrating one would mean using a bad simple captcha image on one
>>>> site, then another form on the other.
>>>> I feel that that would "compromise" the integrity of the page, because
>>>> this one element would differ from one example to the other.
>>>> In my opinion, the demo should stay away from captchas, as to make
>>>> sure the W3C does not endorse it's use in either way.
>>>> Best,
>>>> /Denis
>>>> On 2011-11-17, at 9:33 AM, Phill Jenkins wrote:
>>>>> Dear WAI-EO editors,
>>>>> Regarding the The W3C WAI Education and Outreach Working Group (EOWG)
>>>>> invitation to comment on:
>>>>> Before and After Demonstration (BAD)
>>>>> http://www.w3.org/WAI/demos/bad/
>>>>> It would be good that BAD include a best practice example of CAPTCHAS
>>>>> Regards,
>>>>> Phill Jenkins,
>>>>> IBM Research - Human Ability & Accessibility Center
>>>>> http://www.linkedin.com/in/philljenkins
>>>>> ----- Forwarded by Phill Jenkins/Austin/IBM on 11/17/2011 08:16 AM -----
>>>>> From: "Lars Ballieu Christensen" <lbc@sensus.dk>
>>>>> To: <sec508@trace.wisc.edu>
>>>>> Date: 11/17/2011 08:10 AM
>>>>> Subject: [SEC508] Examples of accessible CAPTCHAS that work well
>>>>> Sent by: sec508-admin@trace.wisc.edu
>>>>> Dear all,
>>>>> Greetings.
>>>>> I�m looking for examples of CAPTCHAS that are both accessible from a
>>>>> formal compliance point of view and work well with a multitude of
>>>>> users. Any references are highly appreciated.
>>>>> Kind regards
>>>>> Lars
>>>>> ----
>>>>> Lars Ballieu Christensen
>>>>> R�dgiver/Adviser, Sensus ApS
>>>>> Specialister i tilg�ngelighed/Accessibility Consultants
>>>>> Tel: +45 48 22 10 03 � Mobil: +45 40 32 68 23 - Skype: Ballieu
>>>>> Mail: lbc@sensus.dk � Web: www.sensus.dk & www.robobraille.org
>>>>> Vi arbejder for et tilg�ngeligt og rummeligt informationssamfund
>>>>> Working for an accessible and inclusive information society
Received on Thursday, 17 November 2011 19:39:00 UTC

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