"I wonder how you know this...."
We firefighters have tinted eye protection attached to our helmets, at least in the fire companies that I have belonged to. Not the greatest, but it helps. It's a wrap around shield that tapers at the ends and is connected to the helmet brim above the ears. They swing up out of the way easily, but can be pulled down in front of your face when protection is needed. There are other versions, but I like these the best. They are made from tinted polycarbonate, so quite tough and heat resistant. These fit well on the old NY Style helmets, but not so well on the OSHA idea of a fire helmet. I have always hated their design, to the point of buying my own NY Style when the company decided to go with them. It wasn't cheap....about $275 plus the cost of the face shield which was about $40 and this was about 45 years ago.
I was a volunteer firefighter since 1959 with several different companies due to my paying job moving. Before moving to NC I had worked my way up to Captain and was also an EMT II and studying to be a paramedic with the rescue squad in that fire company.
My career paying job was as an Automation Engineer (EE) mostly designing automated machine control systems for high speed, high precision, manufacturing lines. But shortly after becoming an EE, I worked on the design team that developed the special cameras that took mapping photos of the Moon from two orbiting rockets. We didn't know the reason for these until a few years later when I was working on the NASA Apollo program. The maps that were made from these photos were provided to the Astronauts in case they landed somewhere other than their planned landing location. The camera had to take photos of the entire Moon, including the back (dark) side. With 1950's camera and film technology and an orbiting camera, this was quite a challenge. About like driving down a road at 64 mph on a Moon less night and taking blur free photos of every house on the street in near total darkness, using film technology. The film used was self developing, much like the Polaroid film of that day. Encapsulated developer and fixer liquids were bundled with the film and spread over the film as it passed over the rollers. Then after several orbits, the images were slow scanned and transmitted to tracking stations, and then later it all ended up being pieced together and the maps were created from it.
The big problem that had to be overcome with this special camera was to find a way to lock the camera on a position while the shutter was open, and hold it pointed at that position until the shutter closed, then jump the camera angle ahead and lock it on the next position and hold it on that position again while the camera shutter again had to stay open when photographing the dark side of the Moon. We finally came up with a way of scanning a narrow area (spot) in a circular pattern and identifying side lit mountain peaks, etc. within the perimeter of this circle and memorizing the position of each within this circle. Once this data was collected, any movement in the following circular scans could be compared with the scan in memory and error signals produced by this comparison was fed to the camera positioning system to constantly move the camera just enough to correct for the orbiting rocket movement. These corrections took place at 120 times per second.
Then, when adequate light had been collected by the main camera, and the shutter closed, another control system caused the camera to jump ahead and begin the sequence of talking the next photo. With the Moon's very bright and very dark sides, controls needed to adjust the camera for the correct exposure between each shop too. We really pushed the limits of camera and film technology to do this, but it worked and worked very well.
Some 15 years later I used the basic design of this camera control system, of course with different optics, to electronically look at a magnified view of an integrated circuit chip and detect it's contact positions. Then switch the optics and look at the contact area of the integrated circuit substrate where the chip needed to be placed. Then remove the optics and place the chip, properly positioned, on the contacts of the integrated circuit substrate. Flux on the substrate site worked as temporary glue to hold the chip in the correct position until the substrate was conveyed through an oven to melt the solder and bond every contact of the chip to it's proper contact on the substrate. The average time required to do this was about 4 seconds and it could do this for each chip automatically and without human intervention, except for an occasional jam. Some of the substrates contained up to 112 chips, and each was placed this way. Each chip was about 0.100" to 0.120" square with up to about 150 electrical contacts, so very fast, high precision automatic assembly work.
Some day when you have your computer apart, look for the CPU module. It has a small metal cover in the center and is attached to the center of a reddish purple ceramic substrate. In a PC there is only 1 chip on the substrate and it's covered by this metal cover. In mainframe computers there are substrates that are up to about 4" square and they have up to about 112 integrated circuit chips on them, which are behind a liquid filled cover and this liquid is circulated to keep this high density circuitry assembly cool. In a main frame computer there can be many of these large modules and the circulated liquid to keep them cool.
Seven years before retirement #1 the company was no longer building new automation, so I was kind-of out of a job and transferring to another plant appeared to be in my future. Then I was approached and asked if I would be the Site Fire Marshal and Electrical Safety Engineer for the 3.2 million sq ft facility here. It was on 1,350 acres too. Since I love it here and was planning to retire here, I decided that this would keep me from needing to move to somewhere across the country, so I accepted the job. It was more than I had expected and I was working 12-14 hours a day much of the time, but 7 years later I retired. During that time I was basically the foreman over up to 6 fire technicians, doing mostly alarm and sprinkler testing. We didn't fight fires unless we had to. The local fire companies took care of the firefighting.
Charley
) they'll definitely get going and pretty much burn all up (excepting a few steel insert pieces). If you can find one of the fan shrouds you can also use that as a booster to get the engine block burning easier.