Hello, my name is Loïc Martínez Normand,
I am a lecturer at the Faculty of Computer Science Engineering
at the Universidad Politécnica de Madrid.
This video explains a decision tree
to ease the application of the EN 301 549 standard
to specific products and services.
This standard can be applied
to any kind of ICT products and services,
but there is one important problem:
How do we know which of the 213 requirements
and 26 recommendations apply to each particular case?
Each requirement and recommendation has its own precondition.
So, if an ICT product or service meets the precondition,
then, that requirement would apply.
But answering 239 detailed questions about a product
is not feasible when the product is still under development
and you need to know which requirements have to be met.
And it is very inefficient if the product already exists
and you want to know which requirements are met.
This is why we propose a strategy based on a decision tree.
The goal is to reduce the number of 239 questions.
Thus, each question in the tree,
concerns several requirements.
And, in addition, the answer given
allows to identify the next question
and that reduces the number of questions required.
Thus, you will need to answer a maximum of 25 questions for each specific case.
Some effectiveness is lost,
because the result of the decision tree
will contain some requirements that may not apply
if the details of the product are analyzed.
Even so, it pays off because the efficiency is improved.
From now on, bit by bit, we will look at the decision tree,
starting with the requirements to be considered
for any ICT product or service.
There are six generic requirements
which need to be considered for any product or service.
Therefore the decision tree does not contain any questions for these.
Some of these requirements are to offer alternatives for biometrics,
to preserve information on accessibility
and not to force the user to perform simultaneous actions.
The first question of the tree has to do with closed functionality.
In each question we will see its identifier - which begins with a "Q"
for later reference
a list of requirements that apply
if the answer to the question is yes
and the next question to be asked.
If the system has closed functionality (question Q1),
four requirements apply and the following question,
on access to visual information (Q1.1) is posed.
If the answer to Q1 is negative, then ...
no requirement of section 5.1 of the standard applies
and the question Q2 is raised, we will see this later on.
The same reasoning applies
if access to visual information is required (Q1.1),
with an additional question
if non-visual access is based on sound (Q1.1.1),
which we'll see right away.
On the other hand, there are also specific requirements
if the keyboard is to be accessed (Q1.2).
If the closed system provides audio information
to facilitate non-visual access (question Q1.1.1),
it has eight applicable requirements
concerning the quality of this sound output,
plus six other requirements on voice synthesis,
if the sound output is voice (question Q1.1.1.1).
Let's turn to the questions about interactive controls,
which are called “operable parts” in the standard.
If the system has actionable parts (Q2)
two requirements apply on how to operate those buttons
and the need for them to be detected without being activated.
And if any of those controls has multiple states (question Q3),
then the requirements that apply are those related
to the possibility of distinguishing its state through several channels.
The next question
has to do with systems that allow voice communication.
In this case (question Q4),
the requirements related to the quality of communication apply
and with the need to offer
real-time text communication (RTT).
For this type of communication
there are specific requirements that we will see right away (question Q4.1).
If the system also provides video communication (Q4.2),
then it must meet four requirements needed
for sign language communication and for lip reading.
As for real-time text communication (Q4.1),
it must meet three requirements about information display,
interoperability and response times.
And if the system is not closed (Q4.1.1),
then it must allow programmatic access
to the information of the text communication.
Question Q4.1.1 is the first
whose answer is known in advance in the tree,
since it is equivalent to the negation of the answer to question Q1
on closed functionality.
This means
that it is not necessary to raise question Q4.1.1,
because its reply is obtained from Q1.
This reduces
the number of questions that are posed in the tree.
Let us now turn to systems with video capabilities.
If the TIC system can play, edit or record videos (question Q5),
then seven requirements are applied,
these concern subtitles and audio description.
And then the question is whether the system has hardware or not.
If the TIC system is hardware, or has hardware (question Q6)
then five generic hardware accessibility requirements apply.
If, in addition, the system has loudspeakers
for speech output (Q6.1),
then four more requirements apply,
related to volume
and compatibility with hearing aids.
Then the next question is whether the system has physical dimensions
that may restrict access by people with limited mobility (Q6.2),
in which case several recommendations on physical access are applied
related to change in level, reach, etc.
If the system has mechanical buttons (Q6.3),
three requirements are applied on this type of controls.
The following section of the decision tree
has to do with the web and digital documents.
If it is web content (question Q7),
then requirements equivalent to those
in AA level of WCAG will apply.
And something similar happens with non-web documents (question Q8),
but with some changes in the wording of the requirements,
and with additional recommendations on subtitles and audio description.
And so we come to the fragment related to software.
If the system is or has software (question Q9),
then general software requirements apply
and after that, specific questions are asked.
If it is non-web-based software with a user interface (question Q9.1),
the requirements equivalent to WCAG 2.0 apply,
classified according to whether or not the software is closed
(questions Q9.1.1 and Q9.1.2, both derived from Q1).
Subsequently, this can involve
operating system requirements (Q9.2),
on interoperability with support products,
which will be different for open systems (Q9.3) and closed systems (Q9.4)
and author tools, which allow you to create content (Q9.5).
To finish the tree
we have the requirements on documentation and services.
The last three questions in the tree
define the requirements that apply
to the product documentation (Q10),
to support services (Q11)
and to ICT systems intended to provide relay services (Q12).
With this we have seen all the questions in the decision tree.
In summary, in this video we have seen
that there is a problem to know which of the 213 requirements
and 26 recommendations of the standard EN 301 549
apply to a particular product or service.
The strategy to solve this problem
is to use a decision tree,
which allows to decide on the application of requirements
with a relatively small number of questions,
which we have described in this video.
Finally, it is important to remember,
that usually an ICT product or service needs to meet
a fairly large set of requirements or recommendations,
depending on the features it offers to its users.