geek – Page 49 – Geeky Girl Engineer

Household Hazardous Waste Disposal

Posted on October 3, 2013 by geek

Previously I wrote, or ranted, about stupid smoke detector design, and at the end of the post I mentioned that smoke detectors have a small amount of radioactive material in them, and thus they should be disposed of properly. I didn’t say specifically how because it really depends on where you live. I live in Virginia, and I have since learned that there is no place in Virginia to dispose of them. My county’s website says they have no way to dispose of them and to try to return them to the manufacturer, but if you can’t find any other way to dispose of them, they can be thrown away in the trash. I contacted Kidde, the manufacturer, and they said they will accept them, you just have to mail the smoke detectors to them. The customer service representative I spoke to said just put “for disposal” on the package, and they will take care of them. I actually had a total of three to return because I had the malfunctioning one plus two ones I had originally bought before I had the hardwired ones installed. So last month, I mailed three smoke detectors back to Kidde. It cost me $6.15, but I now have a clear conscience. This may seem a bit much to some people, but I am an environmental engineer. My career has mostly been dedicated to cleaning up and properly taking care of human and hazardous waste. It has also been about dealing with contamination when waste was not taken care of properly, so there is no way I am going to improperly dispose of waste unless it is completely impossible not to do so.

Here is a fun quirk of United States environmental law, my smoke detectors are non-hazardous because they were used in my house. Those same smoke detectors, if used in a commercial or other non-household setting, are hazardous. Hazardous waste in the US is regulated through the Resource Conservation and Recovery Act (RCRA, pronounced rick-ra). Under 40 CFR §261.4(b)(1), “household waste, including household waste that has been collected, transported, stored, treated, disposed, recovered (e.g., refuse-derived fuel) or reused” is considered to be non-hazardous and exempt from RCRA regulation. There are a bunch of reasons why this exemption is in RCRA, but how you treat your legally-not-hazardous, but technically-hazardous, household waste comes down to a bit of just because you can do something, doesn’t mean you should. However, disposal of household waste is also governed by state and local regulations. Just because federal laws allows you to dispose of household hazardous waste in the trash, does not mean your municipality will because they are the ones who actually have to deal with the waste.

Most people know that fluorescent bulbs contain a small amount of mercury, and thus if you ever break one indoors, you should open the windows and leave the room while the mercury volatilizes. It is because of this mercury that most (or possibly all) municipalities and/or waste disposal companies state that fluorescent bulbs should not be put in the trash. The vast majority of trash in the US is sent to landfills and the rest to incinerators, and mercury does not belong in either of these type of disposal facilities. Also, and just as importantly, the bulbs can easily be broken during transfer from your trash can to the truck, while in the truck (especially if it compacts), at the transfer station, at the disposal site, and all the places in between. If it breaks, the workers can be exposed to the mercury, and thus it is not just about protecting the environment but also the workers.

There is more household waste that is technically hazardous. Aerosol cans can become explosive if punctured. Various cleaning, home maintenance, and vehicle fluids routinely used in household are hazardous to the environment. Conversely, both prescription and over-the-counter (and for that matter illicit) unused drugs should be disposed of in a seal container and put in the trash. Putting unused drugs in the trash is far better for the environment than putting them down the drain where they will eventually get into the waterways. Wastewater plants are not designed to remove chemicals like drugs, but that is a post for another day. [I suppose if someone is trying to dispose of their illicit drugs it is most likely because the police are raiding their house, and they are really not thinking about the environment but about jail, but I still don’t want to drink water with trace amounts of cocaine because some druggie upstream of my water treatment plant was trying to evade arrest.]

The point of all this is, think before you toss something in the trash. Spend a little time on your municipalities website, as most now have them, educating yourself on what can and can’t be thrown in the trash and where things that can’t be thrown in the trash can be disposed. While you are at it, educate yourself on what things can and can’t be recycled in your area. There may be a recycling market in your area for something you didn’t even realize.

Cats Laying on Weird Things

Posted on October 2, 2013 by geek

I have had cats for a couple of decades now. I don’t fully understand them and never will. One reason why is they sometimes lay on the strangest things. I grasp that they like to be on high things because the better to survey their domain or something. Sometimes that can simply mean laying on top of a book, which puts them all of one inch higher, but whatever. Also, they like to lay in sunbeams, but who doesn’t, especially when it is chilly. However, sometimes they lay on things that just seem plain uncomfortable. This morning I found Beatrice laying in a sunbeam, which I get, but using a rock as a pillow, which I really don’t get.

Beatrice with a rock pillow. The rock is a hunk of quartz with mica if you want details.

Beatrice with a rock pillow. The rock is a hunk of fluorite if you want details.

Last year, my now-late cat Puck decided to lay on top of a dustpan, which I seriously don’t understand. Then again, Puck thought basset hounds made excellent pillows when they stopped moving, although I actually agree with this opinion.

Puck laying on top of a dustpan.

Inside a Water Filter

Posted on September 8, 2013 by geek

This is what happens when an engineer with an insatiable curiosity, power tools, and clearly too much time on her hands changes the water filter inside her refrigerator. Yes, that is pretty much it. There really is no other point to this post. Most normal people would take the old water filter and throw it away. I am not a normal person, and I wanted to see inside it, so I cut it open. Warning and reassurance to my mom: I wore a half-face respirator with PM10/VOC filters, goggles, and a leather glove while I cut through the filter. I strongly recommend if anyone else tries this, you do this also. I didn’t want to breathe in the dust or get it in my eyes.

Here is the filter before I began.

Photo 1: Used water filter for my refrigerator, side view

Photo 2: Used water filter for my refrigerator, top view

Here is the cross section after I cut through it length wise.

Photo 3: Water filter after length wise cut

The filter consists of a plastic shell that contains a hollow, round-bottom, cylindrical carbon filter. It is kind of hard to see, but the middle of the carbon filter is hollow. The carbon filter is held in the center of the plastic shell, so that there is free space all around the filter. Here are the two halves of the carbon filter side by side with inside of one shown on the left, and the outside of the other shown on the right.

Photo 4: Two halves of the carbon filter, showing inside and outside

As you can see the inside is still very black while the outside has started to gray. I have a hypothesis for the reason, which I will get to soon.

Here is the plastic shell with the carbon filter removed.

Photo 5: Plastic shell of the filter

Now here is a close up of the inside top of the plastic shell.

Photo 6: Close up of the inside of the top of the plastic shell of the filter

Notice how there are channels formed radiating from the center? The filter only has one opening, the hole in the center in the top, as is shown in the second photograph. Thus, one of the reasons I cut the filter apart was to try to figure out how it works. Water goes in through the center, but how does it get out? What follows is my engineering guess as to how it works. I am fairly sure the water comes in through the center hole, and the water pressure in the house forces it into the hollow center of the carbon filter and then through the carbon in all directions radiating outward. The water then is stored on the outside of the carbon filter until it is pulled by the refrigerator’s water dispenser or the ice maker. I think the white matter that has formed on the outside of the carbon filter that gives it a grayish appearance is calcium and magnesium, otherwise known as hardness. I live in Arlington County, Virginia, and our latest water report lists our water’s hardness as 125 mg/l. According to the United States Geological Survey, that puts our water as just in the hard range.

So if the water is stored on the outside of the carbon filter, how does it leave the filter to get to the water dispenser or ice maker? That is where I think those channels at the top of the plastic shell come in. In Photo 3, you can see the plastic top of the carbon filter fits flush with the top of the plastic shell, but the top of the plastic shell has those channels. Because of the space between the plastic shell and the carbon filter, the water can enter the channels from the outside then flow through the channels back to the hole in the center. However, the now filtered water does not flow back the same hole where the unfiltered water enters.The plastic tube at the top of the carbon filter prevents the filtered water from going back into the filter. Instead the filtered water leaves next to the center hole. In Photo 2, two rectangles can be seen next to the center hole, at approximately 1 and 6 o’clock in the photo. Those rectangles are holes, and it appears that the water that flows through the channels then can exit the filter through those rectangular openings. I can’t tell exactly this happens even though I examined where the filter attaches in the refrigerator. I did consider that perhaps I have the flow direction completely opposite, that is that the water enters through the rectangles, flows through the channels into the open space, then is forced through the carbon filter into the center of the filter. There are a variety of reasons, geometry, fluid dynamics, water pressure, etc., why I am fairly sure this is not the case.

So that is how my refrigerator’s water filter works. See this was educational. It was not just about me having fun with my Dremel rotary power tool and destroying something. Really it wasn’t.

First Time Blood Donor

Posted on September 4, 2013 by geek

Today I donated blood for the first time. Fifteen years ago doing that would be ridiculous because I had such an awful fear of needles. Then I got diagnosed with hypothyroidism, and I had to have my blood taken every six weeks for a year or so until we found the right thyroid medication level. I had to learn to deal with my needle phobia, which I learned today is trypanophobia. I also learned that it makes a huge difference who puts the needle in you. Medical doctors, with the exception of surgeons, are not allowed to touch me with a needle. Only nurses who insert needles on a regular basis may touch me with a needle. If I am having a needle inserted into a vein, I demand a phlebotomist. The other problem I have though is the needle sitting in my vein. It is not the pain. It is the idea of a needle just sitting in my vein that makes me nervous. I had extremely minor outpatient surgery about ten years ago. The nurse anesthetist who inserted my IV was wonderful. I barely felt it, but looking at the IV taped to my hand still made me nervous. Of course in that instance it did not help that the saline bags were kept refrigerated, and since I was dehydrated due to the dictated not drinking after midnight, I had ice cold saline gushing through that IV into my veins. That was the most horrible part of the entire procedure.

Anyway, there was a blood drive at my office today, so I decided to finally conquer my nerves and donate blood. Someone today asked me why I decided to become a donor. Is altruism to strong a word for something like this? Besides being incredibly nervous and a little bit of uncomfortableness, I potentially am saving someone’s life with no harm or risk to myself. So why not? I, or someone I love may, or probably will, need someone’s donated blood someday. Pay it forward, right? In fact someone on Twitter thanked me as a recipient of an anonymous blood donation last year. That made the experience that much better. I donated blood. I am still alive. I didn’t even faint or get woozy. I’m pretty proud of myself.

Partially to keep myself distracted, I live tweeted my blood donation. Here is the Storify of the event.

Caprese Soup

Posted on September 3, 2013 by geek

I love heirloom tomatoes. I mean seriously love them. During the summer, I stop at the farmers’ market almost every week to buy them. One of my favorite dishes to make with them is something I created that I call caprese soup. I named it that because it is fairly similar to caprese salad, but the main import difference is that I keep all the tomato juice. The most important ingredient is of course heirloom tomatoes. Overripe, incredibly juicy heirloom tomatoes are best, like the ones I got at the farmers’ market today.

heirloom tomatoes

The other ingredients are fresh mozzarella, fresh basil, extra virgin olive oil, and balsamic vinegar.

Here’s how I make it.

1. Take the heirloom tomatoes and chop them into bite size pieces. Keep as much of the juices as possible, and put the pieces and juice into a large bowl.

2. Cut the fresh mozzarella into smaller pieces and add to bowl. Add as much or as little mozzarella as you want.

3. Add the fresh basil torn into small pieces. Add the olive oil and the balsamic vinegar, in enough amounts that the tomatoes and mozzarella are coated well. I suggest adding more vinegar than oil.

4. Mix well making sure all the tomato juice, olive oil, and balsamic vinegar are well mixed.

5. Allow to marinate overnight in the refrigerator.

6. Enjoy. I suggest serving with french bread or some other bread that can be used to soak up all the juices to thoroughly enjoy.

It is one of my favorite summer meals, and look how gorgeous it is.

caprese soup

Losing 50 lbs

Posted on September 2, 2013 by geek

I write this post wondering if I will ever publish it. I don’t really like to talk about my weight as it has been a struggle for my entire adult life. However, it is impossible to hide that struggle when the weight loss or gain is on the order of 50 pounds. People who see me everyday and thus might not notice a gain or loss of ten pounds have started noticing my weight loss. I am not exactly trying to hide it, but I am just scared of whether or not I can keep it off. I’ve been here before.

This current weight loss journey started when I moved to the DC area. I’ve written about how I changed my life from one based on getting around in a car to a mainly pedestrian life. I did that mainly so that I wouldn’t have to deal with DC traffic, but truthfully I am not one of those people who loves their car, and I am just as happy walking. In adopting this pedestrian life, I lost about 25 pounds over the course of about nine months. I wasn’t trying to lose weight, and the only reason I knew I was was that every time I saw my physician, she happily exclaimed that I had lost more weight. The only thing I had changed in my life during this time, besides the pedestrian lifestyle, was to stop bringing home sweets. I have a problem with sweets, so I decided for Lent last year that I would eat sweets guilt free outside the house, but I just wouldn’t bring them home. [I’m Episcopalian, and I always try to give up something for Lent.] I knew from experience that if I tried to give up sweets entirely, I would just want them more, and I would doom myself for certain failure.

After my physician’s visit nine months after the first time I had seen her and the realization that I had lost a total of about 25 pounds, I realized some of my clothes had seemed slightly looser. Obviously the weight loss was nice, but I wasn’t entirely sure what I wanted to do. Sure, I wanted to keep doing what I was doing to either maintain that weight loss or perhaps slowly lose a bit more. For the past several decades I have made lifestyle changes that had aided that weight loss, but at this point in my life I had sworn off diets. There has been some research to show that yo-yo dieting is really not healthy, and I didn’t want to do it in any event. I have lost a significant amount of weight twice before. The first time I was in my 20’s and lost about 60 pounds on my own. I did it by a lot of exercise and what I now realize was rather unhealthy caloric restriction. The second time I lost about 40 pounds on Jenny Craig. I couldn’t get past 40 pounds even though I was following the diet fairly faithfully. The fact that I got diagnosed with hypothyroidism part of the way through my diet with them may have affected things. I also think that my calories may have been restricted too much. I exercised very often, and at least at the time, the prescribed Jenny Craig diet didn’t account for calories burned through activity. I know someone currently on Weight Watchers, and she said their plans now have you eat more food based on how much exercise you get. I have no idea if Jenny Craig now does this, but as I know from personal experience that I need to tailor my caloric intake based on my exercise or caloric output. Medical experts generally agree that losing more than a pound of so a week is not generally healthy, and if I were to restrict my calories to less than 1700 calories daily and exercise the way I do, in theory I would be losing at a rate that is not healthy.

So I was down 25 pounds without really trying, and I wasn’t sure what to do. I really loved the idea of losing more weight, but I hated the idea of losing more to only gain it back. Not too long after I started trying to decide if I wanted to try to lose more weight, I heard about Fitbit. I decided to get one and see just how active I was. I discovered that I was quite active compared to the average person, and with the Fitbit, I became even more active. I am a data geek, and I love collecting data on myself. It gave and still gives me encouragement to keep moving and be more active. About a month after getting the Fitbit, I purchased a scale to weigh myself and started using Fitbit’s system to keep track of what I was eating. By then, I had decided I would try to keep losing weight, but I was also not exactly going to diet. That is, I would try to limit my caloric intake by 500 calories a day (to lose a pound a week), but if I went over every once in while when out with friends or something, so be it. I had made enough lifestyle changes before that, once I started counting calories, I didn’t have to change that much anyway.

So now it’s 20 months since I first started losing weight, and nine months since I really started to try to lose weight. I weigh myself everyday, which while some say is not beneficial, I do because I’m a data geek. The more data the better, and I’ve become fascinated with the daily changes of up then down. I’ve also noticed that I tend to be stagnant in weight loss for a week or two, then drop three pounds overnight. While this definitely occurs with my hormonal cycle, it also appears to happen at unrelated times. From what I’ve found searching the internet, this is fairly common. One person has proposed that it is related to water replacing triglycerides in fat cells temporarily, but he readily admits, he has no proof of it. Whatever the reason, it seems to happen to me.

I exercise almost everyday, and I try to walk as much as possible. I log all my food to count the calories. I’m sure to some people this would be beyond tedious, but I feel like I am running an observational science study on myself. I still don’t exactly consider myself to be dieting. If I weren’t trying to lose weight, I might eat a bit more bread or something, but I also realize that if I have any chance of keeping this weight off forever, then how I live my life now is for the most part how I am going to have to live it forever. I will never be one of those people who can eat whatever they want and never exercise and not gain weight. I am fairly sure if I ever stop exercising on a regular basis, i.e. several times a week, I will gain weight. Also, when I say exercise, I am not talking a brisk walk a couple of times a week. I exercise on my elliptical machine for an hour several times a week. I started running several months ago, and I try to go for one or two 3 mile runs plus a long run, which at this time is 5 miles, each week. I do resistance training with free weights and resistance bands. I also walk everywhere and try to go for a walk at lunch every work day.

Now, I’ve lost over 50 pounds total. It’s 55 pounds according to the scale this morning, but I easily go up and down a couple of pounds each week. I suppose I should be happy and proud of myself. I am, but I am also terrified. As I said, I’ve lost lots of weight before. Losing weight, or at least the initial weight loss is easy. Keeping the weight off and losing more is incredibly hard. I am not sure how much more I need to lose. My guess is that I need to lose another 20 to 30 pounds. I’ve dropped three or four dress sizes. I haven’t bought that many new clothes though. The tops are just loose on me. However, I have had to buy some new pants because I can cinch them with a belt because otherwise they would just fall off me, but some I have to cinch so much they look clownish on me. Several people have asked why I don’t buy more new clothes. My answer is two-fold. I hope to lose more weight, and thus I don’t want to buy clothes that won’t fit me in several months. Two, but just as importantly, I am scared that I can’t keep the weight off. I have a huge stack of clothes in my closet that don’t fit me anymore. I can’t bring myself to donate them yet because I am just too scared of my ability to keep the weight off.

I suppose the good thing is that I realize this is not a diet. This has to be a lifestyle change to last my life. To a certain extent, I feel like an addict in recovery. My addiction is food, so I can’t go cold turkey (no pun intended). I have to eat. I just have to always eat smart, and I always have to get a lot of exercise. However, I like what I eat right now. I eat lots of fruits and vegetables. I eat lean meats. I never have been a fan of fried food or many other really fattening food. What I eat now I am entirely happy to eat for the rest of my life. This as opposed to when I was on Jenny Craig. I am not trying to slam Jenny Craig, but at some point, even if I had been completely successful with that diet, I would have had to transition to “real” food. I fix healthy meals and enjoy eating them. I don’t eat disgusting low calorie food just because it is low calorie. I eat healthy, nutritious, delicious food that I happen to make low calorie.

So if you know me personally, that is what is going on with me. That is why some of my clothes are falling off me. Perhaps now, you also understand why I am not screaming from the rooftop that I have lost over 50 pounds because it will just be all the more embarrassing if I gain it back. If you compliment me, know that I appreciate it. I really do. I just don’t have enough confidence in myself to fully be happy and proud of myself. I’ve been here before.

Useless Installation Directions

Posted on August 31, 2013 by geek

Today I installed two new wall mounted light fixtures on my front stoop to replace the old ones. The lightbulbs had burned out in one of them, so I decided to change the light fixtures sooner than I originally had planned. Yes, changing the entire light fixture because the lightbulbs burned out, is a little extreme, even for me, but truthfully the old one was so thoroughly rusted, I could not get it apart to change the bulbs. I wanted new light fixtures that would be more modern and allow for more lightbulbs, so more light would be produced anyway.

I’ve installed six light fixtures already, two wall mounted and four hung from the ceiling, so these two should not be a big deal. I keep forgetting just how useless all directions that come with these things tend to be though. Yes, as a female, even when I am sure of what I am doing, I still tend to read the instructions. I’m funny that way.

Why are the directions so useless? First, the one type of direction I would like for them to have, they almost never have, and that is how to change the lightbulbs. I’m serious about that. I’ve lost track of the number of fixtures where I’ve uselessly unscrewed various finials and nuts in hopes of separating some piece that inevitably is welded together to try to find a place that is large enough to reach the lightbulb. The new light fixtures I installed today are no exception. I unscrewed several finials only to realize a piece was welded. I finally realized it is possible just to stick my hand through the bottom opening and carefully swing the light piece to change the lightbulbs, but I have to be careful. Another annoyance with these fixtures is that the glass sides are held in such a way that during shipping, some of the slipped out of place. Part of the reason I was unscrewing finials was to figure out the best way to get the glass sides back into place. Again, I ended up doing it really carefully and slowly through the bottom.

The second reasons most of these directions are useless is that evidently companies can only afford to print one set of directions for their entire line of fixtures. Below is the single piece of paper that came with these fixtures.

Assembly directions for evidently every fixture they sell

One sheet of paper for five different types of fixtures. Seriously? Does it really cost that much money to print a different one depending on the actual fixture in the box? Perhaps if they did, YOU COULD ACTUALLY READ THE DIRECTIONS. Here is a close up of the directions that, in theory, pertain to my fixture.

My fixture’s installation directions

Yes, on the back were written directions also, but they can be summarized as 1. Turn off breaker. 2. Black wire to black wire. 3. White wire to white wire. 4. Ground wire to green grounding nut. These are of course great, and you, of course, can get them from anywhere on the internet. The best part of all of these directions is that they are somewhat wrong. If you look at the drawing above, the fixture hangs from a crossbar that is mounted to the wall box. This is completely standard. HOWEVER, this is the crossbar that came with my light fixture.

Light fixture’s crossbar

Needless to say, this threw me for a loop. I figured out the reason for it fairly quickly. Crossbars are always mounted to the wall vertically, but the new light fixtures required a horizontal mount. Thus one bar is to mount to the box, and the other attaches to the fixture. Great, no problem, but it really would have been nice if, oh I don’t know, THE DIRECTIONS HAD MENTIONED THIS IS LITTLE CHANGE FROM STANDARD. Even better, one of the fixtures had the screws on the wrong bar. That is, in one of the boxes, the screws needed to mount the fixture to its crossbar, were screwed into the other crossbar. Yes, I did figure out after several frustrating minutes that it does make a difference which crossbar goes to which. It affects the way the crossbar sits in the box and hides behind the fixture.

These directions weren’t even the worst ones that I have seen. The chandeliers that I installed had really useless directions. This is mainly because like all fixtures, they came with the standard directions of black wire to black wire and white wire to white wire. The problem was that the chandeliers did not have either a black or white wire. They had silver wires with clear coating. One had a little sticker labeled “N”, and the other had a little sticker labeled “L”. I just looked at these things wondering WHAT IN THE FLYING FIG IS N AND L? I know what black wire, white wire, bare wire, and even red wire from the wall are. So now there is N and L? Being the chemical engineer I am, I’m think of black as the “hot” wire and white wire as the “cold” wire, so why aren’t they labeled H and C? Ten minutes of internet searching later, I find out “L” means live or line, depending on your source, and thus connects to the black wire, and “N” mean neutral, and thus it connects to the white wire. However, most importantly, WHY THE HECK COULDN’T THE INSTRUCTIONS THAT CAME WITH THE DAMN FIXTURE SAY THAT?

The light fixtures I installed today did however have completely unneeded directions. Below is a photo of the back of the fixture.

Back of the light fixture

The top sticker on the lower right has the completely unhelpful directions “Wall Mount Only [up arrow] This End Up.” Now if you only saw the fixture like this, those might actually be useful directions. However, if you look at the whole fixture, you would notice that the interior of the fixture where the lightbulbs screw in, hangs from the top of the fixture. Therefore, anyone with a passing understanding of GRAVITY would figure out that that end has to be up. So, I’m so glad they put that sticker on there.

Let me be clear, these directions are for do-it-yourselfers like myself. A professional electrician doesn’t need any of them. Thus, why are the directions so damn crappy? Are they to discourage do-it-yourselfers? Do they actually think these directions are helpful? Exactly how much would it cost to print different and readable directions for each type of fixture? Exactly how much would it cost for the design and/or manufacturing department to keep the department who creates these completely unhelpful directions informed when they change important aspects of the design, like using wires labeled N and L instead of black and white wires?

I did eventually get the new fixtures installed, no thanks to the directions. They look lovely, and no duct tape was required, just persistence and experimentation. Each fixture holds four lights as opposed to the old fixtures, which held two, so now there is more light produced. I think they might look slightly modern for the house, but I am planning to eventually replace the front door, and then I think they will work better. Also, the house really needs to be painted, but they has to wait a bit. WIthout further ado, the old and new light fixtures.

Old light fixture

Front stoop with old light fixtures

New light fixture

Front stoop with new light fixtures

Smoke Detector Stupidness

Posted on August 24, 2013 by geek

Last night at 3 a.m. my smoke detectors went off. There really is nothing like being awakened from a dead sleep to that extremely high pitched chirp and a female voice saying “fire, fire.” I, of course, immediately got out of bed and went in search of this supposed fire. There was none to be found. However my smoke detectors assured me there was. I then had to go through the house and pull all five of them from their wiring and in some cases pull out the batteries because pushing the button would not hush them. At 3 a.m., that was so much fun.

When I bought this house it did not have any smoke detectors. It had two wall mounted holders for smoke detectors, one in each the downstairs and upstairs hall. There were none in the bedrooms, and there was no wiring for interconnected ones. I decided early on that as I renovated the house, I would install interconnected wired smoke detectors and bring the house up to current code, even though it was not required. I’m an engineer that way. During Phase 2 of renovations, because the ceiling downstairs had to be opened to install a structural beam, the house lost grandfather status, and interconnected wired smoke detectors now became required by the County. No problem. I was already planning to do it. When it came time to install them, I decided to get combination smoke and carbon monoxide detectors. I had to buy all new ones anyway, so I might as well go for full protection.

This leads me to last night and my need to rant. My detectors are Kiddie brand. I mention the brand because there is an oligopoly of sorts on household fire alert and response equipment. All of them seem to work the same and have the same flaws. Modern houses generally will have interconnected smoke detectors so that if one detects smoke, all the detectors will go into alarm. There should also be one detector in each bedroom and in each hall. Interconnected fire detectors and their location are not universally adopted building code requirements for new construction but are a good idea. If you have a large house, it is possible for one to go in alarm and not awaken a sleeping person in another part of the house. Research has also shown that children do not necessarily wake to a smoke detector at all, in particular the tone. This is partially the reason why voice alarms have been added, but with children, personalized voice alarms with the parent’s voice may be needed to insure children are awakened.

If my detectors detect fire, they set off one set of chirps and say “fire, fire.” If they detect carbon monoxide, they set off another set of chirps and say “carbon monoxide.” If the battery is low, another chirp and “low battery.” Then there is some complicated series of chirp sequences to denote if it was previously in alarm, has malfunctioned, needs replacement, etc. that NO ONE COULD POSSIBLY DISTINGUISH THE MEANING OF AT 3 A.M. Mine were definitely yelling fire last night. As I ran around with a stool trying to figure out what the problem was, the hush button was not working at all. At one point, one of them said carbon monoxide, but I have no idea which one because they are all blaring at me at 3 a.m. The units also have some complicated series of LED blinks to denote in which mode (or possibly mood) it is. This is great, but they are IMPOSSIBLE TO UNDERSTAND AT 3 A.M. Also, as far as I could tell or at least understand, there was no way to figure out which specific detector set off the alarm and thus which one was malfunctioning. Maybe the LED is supposed to tell me this, but I couldn’t figure it out when all I wanted to do is stop the awful noise being blared at me.

Thus if any person who happens to work in smoke detector design happens to read this, these things are too complicated to understand when there is some malfunction or inaccurate alarm. I appreciate the voice that says fire, carbon monoxide, or low battery tells you what the supposed problem is. That makes it much easier to understand than which series of chirps are being blared. However, if you are trying to track down a malfunction, it is impossible. Stopping the blare seems to be impossible short of removing all sources of power. For interconnected detectors, I want and need to known which one started the alarm. I can’t figure out the problem if I don’t know that, ESPECIALLY WHEN IT IS 3 A.M. WHICH IS EVIDENTLY THE ONLY TIME DETECTORS HAVE A FLASE ALARM OR LOW BATTERY.

That ends my rant. While I’m on the subject of fire detectors though, please remember to change the battery every six months. Also, please remember when the detector itself needs to be replaced, never throw it in the trash. Smoke detectors contain a small amount of a radioactive substance. They are perfectly fine to have in your house, but they should not be disposed of in a landfill. Find an appropriate place to dispose of them. [Update: Please see my post Household Hazardous Waste Disposal on how I eventually disposed of my malfunctioning smoke detector.]

Mulching Plant Tour

Posted on August 17, 2013 by geek

About a month ago, I got a chance to tour a recycling plant. This Arlington County municipal recycling plant focuses on recycling yard waste. In the spring, Arlington County has curbside collection of yard waste in paper bags including invasive vines, leaves, dead plants, pine cones, etc. In the fall, Arlington County picks up leaves in paper bags from residents and also from curbside vacuum collection. All year long, Arlington County also picks up brush curbside. All of these waste streams are treated separately at the plant, and the plant also handles dirt and rock excavated during utility work.

The plant manager said he likes to think of the plant as a reutilization plant because something goes in, they process it, and then something goes out. Their operation is really quite impressive, especially when its 2.7 acres total yard size is considered. It is mainly this plant size that limits their ability to accept more waste for processing. Their biggest issue is dirt from pipe breaks etc. that is processed here. They reuse the processed dirt and rock for backfill, but if they can’t find a use for it, they have to dispose of it in a landfill.

The yard waste has to get to 140°F to kill any invasive weeds. Because the plant is located near a residential area, they do not accept food waste because of the odor it produces. They use lime on the yard waste solely for odor control. [Lime the inorganic material, which generally means calcium oxide (CaO) with some calcium hydroxide (Ca(OH)₂) not lime the fruit.] With the leaf waste, they achieve a 66% volume reduction to the leaf mulch product. Leaf bag collection mulch is mixed with dirt for final product.

Tub grinder that processes leaf, brush, wood, and spring yard waste

Dirt processing machine that sorts material by size

Stone crusher machine

Material going into trommel screen for separation. The trommel screen sorts dirt and big aggregate.

Material coming out of trommel screen after separation

As is often the case, fixing a piece of equipment involves a guy standing on the bucket of a front loader using a pole to move things.

Rock and concrete after separation

Dirt for separation by size

Leaf mulch product

Wood mulch product

Yard waste mulch product

The plant uses the product dirt to create this vegetable garden. It had wonderful looking vegetables, and in the past, they have entered the vegetables in the county fair.

Cambridge, Maryland

Posted on August 10, 2013 by geek

I visited Cambridge, Maryland this afternoon. It is a cute little town on the Choptank River on Maryland’s Eastern Shore. I have to admit the town makes me a little sad because it is a historic town and many of its buildings are in disrepair. They seem to be having a bit of a revitalization, which is great, and I hope it continues. Many of the downtown buildings have been renovated and have new businesses. Many of the gorgeous, historic homes have either been maintained all along or have been renovated. There are still many buildings and homes though that need some serious help.

Downtown Cambridge

Law Offices

High Spot

Cambridge Creek towards Choptank River

Cambridge Creek towards inlet

Cambridge Municipal Yacht Basin

Choptank River Lighthouse

Choptank River Bridge