| Expert feedback from John la Roche, water engineer and ex-director of Water for Survival. |
Certificates |
1. Olivers, Ben and Martin's prototype
 
Click here for the full project. |
Effectiveness I was unsure from your description about how everything works, but you have obviously built the device and tested it - well done. All the materials you have chosen should be easily found in a place like Papua New Guinea.
Durability The structure could be quickly erected anywhere and it would easy to replace the bamboo legs, hoses, water bottles and rope. However it could be prone to being knocked over by excited children with the possible loss of water.
User friendliness Having the foot pedal would overcome the problem of contamination by previous users with dirty hands is a good idea.
I assume that the water in the lower bottle would be connected to the hose from which water for hand washing would come. Sucking the end of the hose to get the water to flow might not be a good idea and it could be contaminated with germs.
Communication Children would need to be shown how to use the "contraption" and to learn why washing hands is so important. |
2. Cody and Caleb
Click here for Cody and Caleb's full project. |
Effectiveness What a good idea to fill the container at night while most people are asleep. But there might be times when it didn't rain, or there wasn't enough rain to refill the bottle. Perhaps when this happens there might be a rain water tank that could be used to refill the bottles. The 6 and 10 litre bottles would hold enough water for many hand washes, but they could be heavy to lift and suspend from a string. However the pictures show that you have built and tested this device and you will have overcome these problems. Well done.
Durability It appears that the 10 litre container may be a used wine cask with a tap fitted that might not always be readily available in PNG for replacement when needed.
User Friendliness It is an excellent idea to use clear plastic containers will allow the users to see that water is available for hand washing and how much is left before refilling is needed. Turning the tap on and off might be a place for contamination from users with dirty hands. I assume that sucking the hose would only be done by the person who places the refilled bottles out each morning ready for use.
Communication Good communication would be needed to ensure the device is used correctly and the importance of hand washing is understood. |
3. Tessa - PNG's Perfect Invention!
The water will fall into the funnel which will go down the pipe and add more to the container. When it gets full enough, the water will pour into the sink so you can wash your hands. The two red floating circles will tell you how much water is in the tank. There is a lid for putting soap in to make the water clean. Make sure you put the lid back on after you put the soap
in. Place invention in a place where the rain can reach it.
Materials:
x1 Ice cream container
x2 Plastic drink bottles
x1 Pair of scissors
x1 or more Roll of stickytape
I chose this proto type because its an easy-to-use hand washing object. You don't even need to do anything apart from take the lid off and puting the soap in! |
Effectiveness This is a nice compact device that should be easy to make and transport. What a great idea to leave it out where rain can fill the tank and then it could be easily carried to where it will be used.
Durability The materials should all be easily available in a place like Papua New Guinea and hence easily replaced when needed. It is a simple concept that could be easily replicated.
User Friendliness I assume that the device would stand next a sink where hands would be washed with a little of the soapy water tipped from the container. I think this is an excellent design.
Communication Users would need to be shown how to use the device and the importance of hand washing and cleanliness stressed.
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4. The water solver by Sam and Joseph
How it works:
Water falls in the top of the funnel and falls down the hose piping in to the milk bottle.
What you do:
Then you put your hands through the flap and wash your hands
What you need
4 Metres of hose
4 Milk bottles
1 Roll of duct tape
4 1M+ bamboo
4 50 cm+ bamboo
Why we chose it
Because we thought that the christmas tree frame is really effective. |
Effectiveness This looks a simple device using bamboo and milk bottles. I was unclear how four milk bottles might be filled, i.e. one at a time or all four together, in which case getting four hose pipes connected to the collecting funnel might be tricky. I note the four ties near the base of the legs that would make to device easy to pick up and transport. This is a good addition.
Durability All the the items used to make the Water Solver should be readily available in Papua New Guinea and hence it could be easily repaired and replicated.
User Friendliness I was unsure where the "Flap" that users put their hands through is located and just how the water would be extracted from the bottles for hand washing. However you have built the device and no doubt you have worked this out.
Communication Instruction on how the Water Solver is to be used and the importance of hand washing would be needed.
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5.Water Soap-a-tainea - Courtney and Melissa
 Click here for Courtney and Melissa's complete project.
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Effectiveness What a nice simple device to get soap and water for washing hands and you have made a nice wooden stand to have the device at a convenient height. Well done.
Durability Milk bottles and timber would be readily available so the device could be easily maintained and replicated in PNG.
User friendliness I was unsure as to how the "trigger" to provide water and soap from the containers would work. It might be hard to stop leaks. However the simplicity of the device should make it easy to use.
Communication Because the device is simple it should be easy to show users how to operate the device but the importance of hand washing needs to be stressed.
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6. The germinator - Joe and Oscar
WHY WE MADE IT:
To have a great way to collect water and wash your hands with out buying it.
THINGS NEEDED: Get four steal poles or a triangular frame, 2 ice cream containers, 2 peaces of netting to catch dirt and leaves, a hose or tube for water to run out of.And cut a peace of bamboo in half.
STEPS TO BUILD THE GERMINATOR:
Place up poles or frame. Put half of the bamboo on the top of the frame so it comes together on an angle. This will mean the water goes into an ice cream container which you then put the netting over. Put a hole in the ice cream so that water can go through to other ice cream container with other filter then stick the hose on that. |
Effectiveness Your idea of a "do-it-yourself" hand washing device is excellent. Using a filter cloth to keep out leaves etc. is also a good idea, but would you collect enough water from two half bamboo pieces? Perhaps a very large variety of bamboo would be suitable.
Durability Most of the items should be available in PNG, but perhaps not so easy to find everywhere. The steel frame or legs could be replaced by timber or bamboo and this would make it easier to replicate if steel was not available.
User Friendliness You have made and used the device. Fixing the hose into the ice-cream container might be difficult and I would suggest that after hand washing the hose should be lifted up to save water.
Communication It is a relatively simple device but some instruction would be needed and the importance of hand washing should be
stressed.
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7. THE GERM DESTROYER 3000 - Alex and Loclan
Our prototype is destined to collect rain water from a tree.
You need a 3 litre bottle, two 750 ml bottle, the top of a bottle, 2 small
sticks, sticky tape a hot glue gun (or glue optional) string and 3 straws .Tie string to the the top of the bottle which is sticky tape to the 750 ml bottle
which has a cap in it to stop it from over flowing. The 750 ml bottle is s on to the 3 litre bottle which has a hole at the bottom which has got one straw leading to the second 750 ml bottle which has a straw that dispenses the water into a bucket. If you can reuse the water put it back in the top (if you want ).
When we went through the process of building the prototype we had some difficult problems about the resources because we did not have them so we had to change it to resources that we had. Unfortunately some of the resources we had wouldn't work like one of the 750 ml bottles that couldn't be cut because the plastic was too hard so we used another one that my partner brought the next week. The bottle that we used first was used later of the process of the prototype which was useful to us because we didn't
have any thing to dispense the water so we put a straw in it. |
Effectiveness You have put a lot of thought into your device but you might need more water than could be collected running down a tree trunk. I wonder if straws would deliver enough water for a good hand wash? Returning water for re-use would be good in a water short period of the year, but it could be contaminated by previous users.
Durability You have had to improvise with other materials when what you had in mind was not available. The same thing could well happen in PNG, so well done for trying something else.
User Friendliness I suggest that straws might not give enough water for a good hand wash, although if the straws discharge slowly into a bucket enough water might collect there to give a good hand wash.
Communication The device would need careful instruction for users and the importance of cleanliness and hygiene should be stressed.
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8. The Germ Scaffold - Prototype
Our prototype consists of a just- juice container using a pulley system. The string is connected to a shutter. When the shutter is down, the water will not be able to come out. However when you pull the string, the shutter will go up
allowing water to flow out. There will be an eyelet on one end of the string, and a ping- pong ball on the other side. The ping- pong ball is just the right size to get stuck when it hits the eyelet. Also, there are knots tied into the
string that are just small enough to fit through the eyelet (therefore slowing down the speed of the shutter going down, so youʼll get a hand full of water). So the shutter will slowly close down over the water until the ping- pong ball
gets stuck. If you wish to wash your hands again, you simply pull the string, and a hand full of water will flow out. There will also be a hole to fill the container up again, once the water has run out.
We went through many designs but in the end chose this one because it was
simply simple. The pulley design was the most reliable design we could think
of, and was fairly fool proof. Also it wouldnʼt waste water so we could get the most out of the water that we use. We also thought that it wouldnʼt be faulty and would stand for a fair amount of time. We found it hard to only make it out of resources that could be found in Papua New Guinea, but in the end, we got there. So overall we chose this prototype because of its reliability, and how easy it is to use.
To make this you will need:
- A three litre bottle
- Bamboo
- Wood
- Strong tape
- String
- Shoe eyelet
- Ping- pong ball
- A small weight
So we hope that this will act as a good hand sanitizer in Papua New Guinea. |
Effectiveness You have thought of many things and I like the idea of a ping-pong ball and eyelet to slow down the flow. The shutter might be hard to seal for anything more than small quantities of water. Using string and pulleys to release enough water for one hand wash is a good idea.
Durability You have thought about the materials that might be readily available in PNG and that is important. However the strings and pulleys would need a robust frame to hold the weight of a three litre container as well as anchoring the pulleys.
User Friendliness You have given thought to providing only enough water for a hand wash and this would save water for other users.
Communication This device would need carful instruction to users to ensure they used it correctly. Hygiene and health education to stress the importance of hand washing would also be needed.
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