Design a fire alarm system for the deaf.

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Design a fire alarm system for the deaf.

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shrutc · Answer 1 · 2021-04-06T10:15:56+0000

Clarifying question – is this an alarm system installed in house or is it a digital alarm used in clocks and phones? I am assuming this for the ones installed in clocks and phones. So, I will build an alarm or clock application that can be used by the deaf.

Persona – Deaf people who use alarms in clocks and phones. I am choosing this persona and use case as it seems like something that is used on a daily basis and would have more adoption.

User pain point –

1. The major pain point is that existing alarm systems do not serve the deaf as they are predominantly based on sound.

2. Phone based alarms do have vibration settings but this is not very reliable and requires the phone to be kept close by to feel the vibrations

3. They have to rely on a third person to wake them up or remind them of certain events.

4. They need to keep checking the time or remember to keep an appointment or write it down.

Use cases that the alarm system should solve

1. Deaf people should be notified of the time or event that they may have set in their phones and so that they are more self-reliant.

2. Deaf people should be notified irrespective of the proximity of the device.

Use case 1 is most priority.

Solution Options

Deaf people have their other senses heightened a lot so, I would go for a system that can leverage other senses apart from sound.

1. Reuse the vibrations setting that phones have. As I mentioned most phones have a vibration setting but it is either too low or not present for alarms. We can build an option to increase or decrease vibrations so deaf people can use the highest setting as an alarm.

2. The app can use screen brightness as a mode of alerting the user. When the alarm goes off, then the screen can become really bright, or the phones torch can be switched on.

3. These days AI and machine learning can be leveraged to make two devices talk to each other. The application can be linked to a wrist-band or the light bulb. Once the application is downloaded on a phone, then once the alarm goes off, it can communicate and trigger the band to vibrate or the bulb to light up.

Solution prioritization based on impact and ease of implementation.

Solution	Impact	Ease of implementation	Priority
1	High	High	High
2	Low	High	low
3	High	Low	medium

As a product for the MVP, I would start with solution 1 which will help solve use case number one. Next, we can work on solution 3 which also helps solve the other use case.

To summarize, I am focusing of deaf people and their daily trouble with the normal alarm systems in devices such as clocks and phones. The use case is to make them more self-reliant and to alert them when an alarm goes off.

Ram Krishna · Answer 2 · 2021-03-21T13:41:02+0000

Sure.

Clarifying the scope

Me: Is the user completely deaf or has partial hearing?

Interviewer: Completely deaf

Me: Is this for residential usage or commercial building?

Interviewer: Residential

Me: Does the product need to be physical or digital / app-based?

Interviewer: Your choice

Me: Final question, is it ok to assume that the users can see, smell, taste, and are mobile.

Interview: Yes, go ahead.

Summarizing: Design a fire alarm for completely deaf users for residential usage. The users do not have any other constraints. I will let the pain point dictate if I would go with a hardware or software route.

Me: Now that I understand the question, Let me share a rough structure I have in mind. I am going to think of the goal of this product, then what we should build- such as users, pain points, and solutions, followed by final consideration like how would I measure success. Does that sound good to you?

Interviewer: Yes, go ahead.

Starting with the mission/goal - Saving lives: To provide a timely and accurate warning to all members of the household including those who are deaf

For the objective of the product, I would focus on engagement which is an indicator of the value we are providing to the users who are completely deaf

Me: Next, I would want to look at users, archetypes, personas. Could I take a minute to put my thoughts?

First, I would like to point out there are various users that need to be taken into consideration while designing this product- The deaf users, people who live with the deaf users, neighbors, Fire responders. Here I would focus on the interaction of the deaf user with the product.

Since it is a mandate for homes to be equipped with a fire alarm, I would assume all the houses already have one or many. So instead of focusing on replacing them with a brand new product, I will focus on augmenting the existing setup.

Me: I am going to take a moment to see if I can segment the deaf archetype further to see if I can find interesting pain points so that I could empathize with them. If there are no specific segments, I would go with the broad user set of deaf users for the sake of this interview.

Based on demographic:

Age: Young independent adults who were born deaf or have become deaf due to an accident to Seniors who have become deaf due to age

Tech savviness: Who are highly tech-savvy to people who are not (possibly seniors)

Location: Being at home or away from home. A related dimension would be to be alerted when there is an alarm in the neighborhood as well.

I see an interesting user segment of Seniors who may not be tech-savvy to focus on since the solutions when developed for them can help the wider user group as well. I will also primarily focus on alerting the user when they are in the house and of threats from within their house. Does that sound good

Interviewer: Yes, go ahead.

Me: Let me take a moment to write down the pain points

I will look at the user journey to understand the pain points - Normal operation, during an emergency, Post an alert.

Normal Operation:

1] I want to test if the fire alarm is working, but I am unable to since it only has sound-based validation.

During an emergency

2] I want to be alerted of a potential fire hazard, but the current fire alarms only have audible alerts.

3] I want the fire station to be alerted in case of a fire hazard, but I don't know or get a confirmation of the same.

4] I want the fire station to control the fire alarm and provide me instructions to escape, but I cannot follow any voice-based instructions.

Post an alert

5] I want to turn off the fire alarm in case of a false alert, but I do not want to climb and push the button.

Of these pain points, I would like to focus on [2] and [4] since it is core to our objective of saving lives. Is that good?

Interviewer: yes

Summarizing: Design a fire alarm for completely deaf users for residential usage, with a focus on seniors who may not be tech-savvy. The key pain points I am focusing on are around operations during a fire hazard.

Me: Let me take a couple of mins to brainstorm solutions

a] Connected house

Devices at home are connected with the fire alarm like TV and appliance

Alerts the user through visual clues and vibrations and provides some omnipresence.

b] App on the mobile phone

a mobile app, that is integrated with the fire alarm

Alerts the user through push notification and vibrations

c] Hologram solution

Personal hologram solution that is installed on top of the fire

That can alert and as well guide users through sign language on the next steps to be taken in case of fire alarm

d] Wearable

A simple wearable that could be worn

which will alert through vibrations and can be used for letting emergency services know, through pre-built alerts, etc.

Prioritizing the solution based on impact, effort, and as well mapping it to our goal.

The hologram solution is really cool but is difficult to implement and also may not help to wake up users from sleep. So I would look at this option in addition to something else as it addresses pain points [4]. Similarly given our user segment is not highly tech-savvy, I will rule out the connected house, as it may be expensive as well and again may not help when in sleep.

Of the remaining two solutions, both mobile app and wearable are good solutions. Again, given the users may not be constant users of mobile phones, I will first start with the wearable.

Let me explain the wearable solution a little more

Entry point: A simple wearable that matches the style of the senior age group, like either a bracelet or a necklace that the senior could wear which will alert them through vibration when there is a fire hazard. This is something that will help them even during sleep.

How it works: It gets activated as it is connected to the fire alarm within the house. The same wearable could have some simple physical control buttons to acknowledge the alert, respond to alerts like turning off in case of a false alarm, informing emergency services, etc.

Critical action: The user acknowledging through the physical buttons on the wearable whenever they get alerted

Me: Any questions on the solution

Interviewer: Good, could you let me know, how you would measure the success?

Me: Sure. For this product, the most important metric is % of people who got alerted in correlation to the fire alarm and took one of the critical actions of acknowledgment.

Let me also touch downside of this metric, as I said this single metric does not tell the full picture, like referrals, etc. For example, I would like to track if the users are recommending this to others in their community to track adoption. Also, it is not clear what is driving this metric, meaning if the metric is low, why is that so. I would like to track if this is being worn always, battery replacements, etc.

Let me summarize: Design a fire alarm for completely deaf users for residential usage, with a focus on seniors who may not be tech-savvy. The key pain points I am focusing on are around operations during a fire hazard. We looked at few solutions and narrowed them down for this exercise to a wearable that will alert through vibrations and visual indicators. It also has simple physical controls. We also looked at metrics to measure the success of this solution and a couple of counter metrics as well.

It is only starting point we just picked one user segment, a couple of pain points, and one solution. I can see how this wearable could be further extended, to even get activated based on tuning into fire alarm sounds, included with GPS, etc. which will help with neighborhood alerts and will increase the coolness quotient.

kuma0177 · Answer 3 · 2020-03-30T22:52:39+0000

Clarifying Question - Fire Alarm System Functioning:

Flashes and beeps loudly when it detects smoke above a certain threshold
Can be turned off by fire brigade for office buildings or by individuals in a house
Is often connected to the fire department

Clarifying questions and assumptions:

Fire alarm - Alerts the room occupants about a potential fire hazard and asks them to evacuate the place.
Deaf - can see things (yes), can not hear things at all. They don’t have any other major physical constraints in terms of walking etc.
Is this for a residential or professional setting - Residential

Goal: To have an alarm system that can be easily discovered by deaf people and allows them (along with non deaf users) to discover fire hazard and vacate a place.

Primary Users:

Deaf users - These may be fully or partially deaf users, who can’t really hear things.

Secondary Users:

Secondary users: These users not physically challenged in any way and may be living or working with deaf users.

Problems faced by deaf users:

Can’t be alerted via sound since they can’t hear it
Don’t know if the alarm is turned off if they press a button the fire alarm system.
They often can’t speak properly due to their inability to hear and learn how to speak. So it may be hard for them to inform their friends or families in the same house about a fire. Also hard for them to call 911 and inform that there is a fire.

In terms of the above problems, I want to focus on #1 and #2 since they are usually the biggest problems in the usual day to day scenarios. For #3 a well informed deaf person would know about tone-deaf options for deaf and mute users.

Below are some solutions to this problem:

Smart Fire Alarm -
1. Safety app that sends emails, push, SMS, and calls informing the user and relevant parties that there is fire and which fire sensor in the house detected it. Ability to deactivate alarms from mobile phone app.
2. Sound, light, and hazard vibrators - Home fire alarm that beep loudly and also project bright light signs that inform the deaf person that there is an alarm. There will also be strong vibration integrated in these room alarms that will not just beep, project light, but also vibrate strongly to get attention.
3. Simple instructions on the alarm devices to deactivate a false alarm.
Fire Roomba - Small robot that can move in the house like a Roomba with bright lights flashing and indicating that a potential fire has been detected and where it is.

I will prioritize between these two ideas based on the following dimensions:

Impact on user experience (safety, being able to alert quickly, and ease of canceling false alarms) and engineering cost

Based on these #1 - smart fire alarm seems easier to implement in terms of engineering effort. It will also have a bigger impact on users since they can be alerted about fire hazards even when they are remote.

Success Metrics:

Purchase volume
Customer satisfaction rating (NPS, referrals)
App usage - MAU for users of fire alarm

Sanchit Gupta · Answer 4 · 2020-04-28T05:02:50+0000

Clarifying questions:

Is this fire alarm supposed to be in the house? In an office builing? (Interviewer says let's assume house)

Can we assume completely deaf? (Interviewer says yes)

Are there any constraints? (Interviewer re-iterates that the deaf person can't hear)

Is this in US (Interviewer says you can assume yes)

User:

Deaf
- Can't hear
  - Can see, smell, touch, taste
People who aren't deaf probably live with the deaf person that also need to be alerted

I'm going to focus on the deaf user, but also design it to be able to be used for someone who's not deaf that may be sharing the home with the deaf user.

Goal: Create an affordable fire alarm system that works for deaf people and fully fuctioning hearing people for the household.

Problems with existing solution: It's mostly sound based (sometimes flashing flight too) which doesn't work for a deaf person.

Use cases:

As a deaf person, I need to know this works for the deaf and be able to buy it
As a deaf person, I need to know how to set it up and be able to test it
As a deaf person, I need to know that there is battery in this, know when and how to replace it if needed.
As a deaf person, I need to be able to be alarmed, whether or not I'm at the location
As a deaf person, I need to be able to turn it off

Potential solutions:

Regular alarm sound + flashing light when on + mobile app that alerts (sound + vibration + blinking flashlight) you about the fire
- As many users as they want can sync to the fire alarm system and then get alerted from their mobile app, regardless of their location. This is along-side the normal fire alarm alerts such as the alarm and flashing lights. They can press a button to end alert if they think it's a false alarm. This will reset again in 30 seconds if the system thinks the user is wrong.
- A flashing light + push notification can indicate battery is low and instruction manual + push notification explains how to replace the battery/ where to buy it from
  - Pros:
    - Little change for non deaf people
    - Still cheap to build
      Can know about fire even when not in the house
  - Cons:
    - For deaf people, if they lost their phone or their phone dies, their fire alarm system is off
    - Alert may not be strong enough
Multi-light flashing system
- Comes with multiple light system that deaf people can place in multiple rooms. If the fire alarm goes off, all of them start flashing and the main one buzzes and flashes too
- Different pattern of flash (slow blinking) to indicate battery is low
  - Pros:
    - Fire alarm is not off when phone is dead
  - Cons:
    - Can only know about fire when at home
    - Initial set up takes some work
Auto-texts you + calls 911 so someone comes to your house ASAP
- Pros:
  - Help is already on the way
- Cons:
  - May be overly sensitive and bother the authorities too much
  - Slow to alert you

Success Metric:

Number of units sold
Reviews
Time till "end alert"
- Lower the better

Recap:

I would go with option 1 because I think as battery lives keep increasing, phones being dead is a smaller and smaller time period. Additionally, ability to message you when you're not home > time when phone is dead for most people (I'd validate this assumption with data). We can also include features like having it auto-text you so it is an even smaller sample size (some people still receive texts on dead phones in the US via iMessage on their laptops). I would sell option 2 as an optional accessory for it.

Mahnaz Majeed · Answer 5 · 2020-04-01T13:41:16+0000

Fire alarm for the deaf

What - Alarms may have visual, movement and sound features to get the attention of the intended user, should be practical for night and day environments with natural lighting or indoor lighting. Fire alarms are generally a loud sound that can be heard at a distance and might include a red blinking light in a highly visible location to attract maximum attention

Why - The goal is to immediately alert people to exit safely from a building or premises.

How - The alarm is triggered by smoke detectors or some other form of heat detection or lighting, which initiates the alarm to go off.

Who - The user persona assumptions of a deaf person are as follows:

Able to navigate outdoor and indoor physical spaces without requiring audio cues
They are keen observers and tend to have other heightened senses which may be one or more like touch, sight, smell, and taste.
They may be more focused on an activity because they don't get distracted by the noise of everyday life
They may or may not have another sensory disability, might be partially deaf as well.
They might use sign language, lip-reading and gestures to communicate and not everyone may be able to understand them.
In this case, we will assume the product is for a user in a developed country with standard infrastructure norms like existing smoke detectors and fire exits.

Solutions:

Idea	Sight	Touch	Smell	Alert Score (1 to 5) 5 being most effective	Indicate the direction of safe escape
A vibration which gets stronger as time lapses (till it is shut off)	No	Yes	No	4	Yes
A colored and fragrant smoke released periodically from overhead smoke detectors	Yes	No	No	3	No
A bright light flash from the outside of the premises	Yes	No	No	2	Yes
A blinking light that turns on and shuts off all other lights intermittently, installed with room lighting.	Yes	No	No	5	Yes

The colored smoke can be messy and restrict sight, that would be a safety hazard. The bright light flashing from outside will not work when the sun is out, so it also is not effective. Let’s assess the two use cases that scored 4 and 5.

I would test both the solutions with a prototype.

I would test to see what alerts deaf people when they are in different states of consciousness - awake and asleep.
I would test them for when they are focussed on some activity versus when they are lounging (like watching TV).
I would test the level of vibration that would get their attention, and see if that works for hearing people as well. It cannot be a very high vibration that disorients or scares normal people.
I would test the brightness of a blinking light that people generally respond to as a call to attention ( taking into account what ambulances probably use as a baseline).

Once I have sufficient information to assess the user response to the above, I would narrow down on the feature and consider the following factors before making the decision.

Can it be integrated into existing infrastructure?
Will it cost much more than an average alarm system?
What kind of resources would be required to build such a product?
Can existing parts be used to develop this product or does it require some custom manufacturing?