ThinkStock/Erin McCarthy
ThinkStock/Erin McCarthy

What’s the Deal with Those Last 4 Digits on ZIP Codes?

ThinkStock/Erin McCarthy
ThinkStock/Erin McCarthy

Almost everyone knows their five digit ZIP code, and probably a few others within their city, but what’s up with the extra four digits you sometimes see on mail?

Let’s start with those first five digits you’re already familiar with. In the early 1960s, the U.S. Postal Service could see that the old Postal Delivery Zone System was outdated and couldn’t handle increasing mail volume and urban and suburban expansion. To keep the mail moving efficiently, the Postal Service introduced the Zone Improvement Plan (ZIP) in 1963. A five-digit code was assigned to every address in the country—the first designated a broad geographical area or group of states (“1,” for example covers New York, Pennsylvania, and Delaware), the next two designated a region or large city in that area (“91” covers Philadelphia) and the last two represented a smaller delivery zone or group of delivery addresses in that region. 

Over the next two decades the ZIP system became strained, too, and in 1983, the Postal Service expanded it to create the ZIP+4 system, tacking on an extra four digits at the end of the old codes. These new digits identified an area—like a group of apartments or office buildings—or a high-volume mail receiver within a five-digit delivery zone to help with mail sorting and delivery. The sixth and seventh digits of a ZIP+4 indicate a “delivery sector,” like a group of streets, P.O. boxes, a group of buildings, or even a single high-rise building. The eighth and ninth digits designate a “delivery segment,” like a specific side of a street, a floor in an office or apartment building, or a specific department within a large office. 

Getting the public on board with the regular old ZIP codes had been hard enough (some people were annoyed they had another number to remember in addition to telephone area codes and their Social Security number, while others thought that being represented by a number was dehumanizing and un-American), so the ZIP+4 never caught on with people. Fortunately, around the time the expanded codes were implemented, the technology available to the USPS meant that people didn’t have to remember or use the full code. Automatic mail sorting systems apply a Postnet barcode to mail items that corresponds to a full code, and multi-line optical character readers can determine the correct ZIP+4 from the barcode and written address. 

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What’s the Difference Between Prison and Jail?
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Many people use the terms jail and prison interchangeably, and while both terms refer to areas where people are held, there's a substantial difference between the two methods of incarceration. Where a person who is accused of a crime is held, and for how long, is a factor in determining the difference between the two—and whether a person is held in a jail or a prison is largely determined by the severity of the crime they have committed.

A jail (or, for our British friends, a gaol) refers to a small, temporary holding facility—run by local governments and supervised by county sheriff departments—that is designed to detain recently arrested people who have committed a minor offense or misdemeanor. A person can also be held in jail for an extended period of time if the sentence for their offense is less than a year. There are currently 3163 local jail facilities in the United States.

A jail is different from the similarly temporary “lockup”—sort of like “pre-jail”—which is located in local police departments and holds offenders unable to post bail, people arrested for public drunkenness who are kept until they are sober, or, most importantly, offenders waiting to be processed into the jail system.

A prison, on the other hand, is usually a large state- or federal-run facility meant to house people convicted of a serious crime or felony, and whose sentences for those crimes surpass 365 days. A prison could also be called a “penitentiary,” among other names.

To be put in a state prison, a person must be convicted of breaking a state law. To be put in a federal prison, a person must be convicted of breaking federal law. Basic amenities in a prison are more extensive than in a jail because, obviously, an inmate is likely to spend more than a year of his or her life confined inside a prison. As of 2012, there were 4575 operating prisons in the U.S.—the most in the world. The country with the second highest number of operating prisons is Russia, which has just 1029 facilities.

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What Do Morticians Do With the Blood They Take Out of Dead Bodies?
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Zoe-Anne Barcellos:

The blood goes down the sink drain, into the sewer system.

I am not a mortician, but I work for a medical examiner/coroner. During an autopsy, most blood is drained from the decedent. This is not on purpose, but a result of gravity. Later a mortician may or may not embalm, depending on the wishes of the family.

Autopsies are done on a table that has a drain at one end; this drain is placed over a sink—a regular sink, with a garbage disposal in it. The blood and bodily fluids just drain down the table, into the sink, and down the drain. This goes into the sewer, like every other sink and toilet, and (usually) goes to a water treatment plant.

You may be thinking that this is biohazardous waste and needs to be treated differently. [If] we can’t put oil, or chemicals (like formalin) down the drains due to regulations, why is blood not treated similarly? I would assume because it is effectively handled by the water treatment plants. If it wasn’t, I am sure the regulations would be changed.

Now any items that are soiled with blood—those cannot be thrown away in the regular trash. Most clothing worn by the decedent is either retained for evidence or released with the decedent to the funeral home—even if they were bloody.

But any gauze, medical tubing, papers, etc. that have blood or bodily fluids on them must be thrown away into a biohazardous trash. These are lined with bright red trash liners, and these are placed in a specially marked box and taped closed. These boxes are stacked up in the garage until they are picked up by a specialty garbage company. I am not sure, but I am pretty sure they are incinerated.

Additionally anything sharp or pointy—like needles, scalpels, etc.—must go into a rigid “sharps” container. When they are 2/3 full we just toss these into one of the biotrash containers.

The biotrash is treated differently, as, if it went to a landfill, then the blood (and therefore the bloodborne pathogens like Hepatitis and HIV) could be exposed to people or animals. Rain could wash it into untreated water systems.

This post originally appeared on Quora. Click here to view.

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