Hey thanks for watching this is part 2 in our series about the EPA exam. The EPA 608 certification. If you didn't watch part 1, then definitely go back and watch part 1. If you're not studying some of the other resources from mainstream engineering EPA, test, comm or the ESCO Institute, those are the resources to really prepare you for the exam.

This is just a supplementary kind of quick review. Maybe a nice little thing to cover right before you take the exam, or maybe your first introduction to it. Like we mentioned in number one. You first have to know the basic refrigerant circuit.

You should know the terms CFC h, CF c, hf c, hf, o and HC, but now we're going to talk a little bit more about some specific things that you need to know in order to do well on the exam, but also some things that are just Really important general knowledge about our industry and the EPA right off the bat I want to get to some dates and dates are one of the more boring things to memorize, but you are gon na want to memorize these dates to take your EPA 608 exam. So one date that comes up a lot when you're looking at the history of some of these EPA standards is the Montreal Protocol. So the Montreal Protocol was an international treaty designed to protect the ozone layer by phasing out the production of numerous substances responsible for ozone depletion. So we're talking about refrigerants that carry chlorine, but there's also bromine as another substance and a host of others.

But those are some of the most common and it was agreed upon the 16th of September 1987. So that's when it was agreed on and it went into force on January, 1st 1989. So all the way back all the way back. At that point it went into force September 16th.

1987 is really the first date that we really took the stratospheric ozone protection seriously and all these other dates sort of come after that January. 1St 1992 was when it was made mandatory to use recovery equipment in order to pool refrigerant out of a car out of Motor Vehicles, so that was January. 1St 1990 to January. 1St 1992 is also when they called for the phase outs as initial initially when they called for the phase-out of CFCs and HCFCs again CFCs.

Most common ones are twelve. That was the first refrigerant that they commonly referred to as freon, which was a brand name. My DuPont and then are also r11 HCFCs, most commonly r22, which blood people also called freon. That was an H, CFC, hydrogen, fluorine chlorine, carbon and again it's that chlorine molecule.

That goes into the upper stratospheric ozone and breaks down the o3. And that's what we're concerned about in terms of ozone depletion potential ODP. So again that was July, 1st 1992, since November 15, 1993. That's when all new recovery equipment had to be equipped with low loss fittings.

Now some people will say that low loss fittings have to be used on gages, that's actually an area that is a little confusing because most of the EPA literature that you read just talks in terms of recovery equipment, low loss fittings are just a good best practice. On gages anyways, I like ball valves, that's something that's what I prefer on my gauges or probes. Definitely, since November 15, 1993 you've definitely needed to have low loss fittings on your recovery equipment specifically and also recovery of equipment. After that November, 15th 1993 must be certified by the EPA so again the odds that you're going to have a recovery machine that was made prior to 1993.

At this point, pretty much moot so all of the recovery equipment that you work on or work with nowadays is going to be EPA certified November 14. 1994 is the date at which all technicians, when you work with these regulated refrigerants back, then it was specifically CFCs and HCFCs refrigerants. With that chlorine molecule, you had to be certified by the EPA since December 31st, 1995 CFCs can no longer be legally manufactured or imported into the United States. Supplies of CFC refrigerant for equipment servicing can only come from recovery, recycling or reclamation which, similar to that December 31st, 1995 ruling about CFCs.

Now in 2020, we had the same phase out of HCFC, so our 22 had the same thing. Currently, our 22 is legal to charge. It is legal to recover, you can operate in our 22 piece of equipment, but manufacturers cannot make new r22 and they cannot import it from foreign countries. So we're not allowed to have a new supply of our 22.

We have to only use either stockpiled, it's already here or our 22, that has been recovered by a technician and then reclaimed in a certified reclamation facility. So again your two dates they're being December 31st, 1990. Five! That's! When that happened. Four CFCs are 12 being the most common January, first, 20, 20 being the day that that happened with HCFC, specifically, are 22 being the most common since November 15th 1995.

It has been illegal to vent any refrigerant, and that includes substitutes. That includes CFCs, HCFCs or HFCS, or even HF OS. Nowadays, the only refrigerants we can legally vent our refrigerants that are specifically given that exemption by the EPA with which the most common would be co2 and our 290, our 290 known as propane a couple other things to mention that are just sort of important things to Know they would be on the core test, but also just generally valuable, to a technician. One is that refrigerant recovery, cylinders are really refrigerant.

Cylinders in general are regulated by the DoD, the Department of Transportation, not by the EPA, so because these cylinders are going to be transported across the road. It's the Department of Transportation that regulates those tanks and those tanks used specifically for recovery, have a yellow body and a gray top. So that's the standard for recovery, tanks and again, like we mentioned before, you only fill those to 80 percent liquid maximum refrigerants that are heavier than air. They can fill the room from the bottom up and they can cause health problems as you breathe them in and it displaces oxygen, including death.

So you need to be very careful with handling refrigerants and, while we're on the topic, good, PPE, to use or necessary PPE one would definitely be to use safety glasses whenever you're working around refrigerant, because you wouldn't want to get anything in your eyes and in general, Using gloves when working around refrigerant, especially when you're connecting and disconnecting never leave your hands in refrigerant, and if there is any sort of accidental thinning, you need to make sure to get to properly ventilated area quickly. So again, we do not purposely vent refrigerant. There are some cases where accidentally that can happen, or you can have a significant leak and you need to make sure that you're not in a room that has high concentrations of refrigerant, because it can lead to that asphyxia. Due to the room filling from the floor.

Up with a heavier than air virgin as refrigerants are some other terms that you'll see a lot is psi which stands for pounds per square inch. That's a pressure gage, but we will typically use PSIG. That's pounds per square inch, gage, meaning that the gage has already been recalibrated to atmospheric pressure. So it's been zeroed out at 14.7 PSI a because 14.7 PSI a pounds per square inch at saluté.

That is the pressure that the atmosphere places on us at sea level. So most of your gauges are going to be zeroed out at that fort with that 14.7 already calculated in so in order to convert psig to psia at sea level. All you do, is you take your PSIG reading and you add 14.7. So, let's look specifically at this list of refrigerants.

We've got our 12, which was one of the first to go away, because it's a CFC and you'll notice that that has an ozone depletion potential of 0.8 to r11 was one of the worst offenders as far as odin ozone depletion potential, so r11 had an OD P of one r12 wasn't quite as bad, but then you can see that our 12 also had a global warming potential of 10600. So it was really bad from both stand points both of those numbers, ozone depletion potential and global warming. R22 was quite a bit better. On both fronts as much lower ozone depletion potential and lower GWP.

Now, when a lot of these, when these rules came out - and they were mostly looking at ozone protection - they weren't necessarily looking at GWP back to the Montreal or top Protocol, our 404 a and r410a, they have zero ODP, and so they were 134a. Also being an example of this there HFC, so they have a zero ozone depletion potential, but some of them still have pretty high GW PS. In fact, you can see that our 410 a has a higher GWP than our 22 even did, but we switched to it because it had a zero ozone depletion potential. Now you look at things like our 290 ammonia, co2 and then the hf o 1.

2. 3. 4 YF, which is used in cars they have much lower. They have zero OD PS, but also have much lower GWP s.

Global warming potential co2 is the kind of the refrigerant that's used that has the the baseline number on GWP it as a GW P of 1 1 term that you're gon na see on the EPA quite a bit and there's some confusion about this. Is it will talk in terms of evacuating refrigerant, the EPA exams, sometimes we'll say, evacuating refrigerant when we say evacuation in the trade, we are talking about pulling a vacuum, and when we talk about removing refrigerant, we call it recovery, but just keep in mind sometimes in Some of the literature, the EPA will say, evacuating refrigerant and that's the same as recovery, it's taking refrigerant and putting it into a tank two different types of recovery. You have system dependent recovery devices which actually rely on a working compressor, the actual system, components to function and self-contained recovery devices which have their compressor. So those would we would call an active or self-contained system.

Nowadays, we almost all use self-contained systems, but you need to know about system dependent. You can only use system dependent cover II when the system contains less than 15 pound of refrigerant, and you have to have a functional compressor in order for that to work again, you can always use a functioning system to get most of the refrigerant out. If you have a compressor, that's working, you can just pump refrigerant out of the liquid line into your tank, making sure that you don't overfill using a scale, those sorts of things, but when you're done, you still have to use your self-contained or active recovery unit. In order to pull the rest of that refrigerant out, especially in the vapor phase, when pulling vacuums on the system or evacuating the system, it's good to know the kind of the basic standard that we need to pull.

I have whole videos on evacuation, which you can look up to understand how to do it, but when we evacuate that means that we're pulling air and moisture out of the system once we've actually recovered, all the refrigerant and that's important to do is anytime. You have a sealed system and you're going to recharge it. The standard there is to pull it down below 500 microns to 500 microns or below. That is a measure of deep vacuum.

I don't know for a fact that that's on the exam, but it's just really important common knowledge, and it is on a lot of exam. So just know that in general it's generally accepted practice that pulling a system or below 500 microns and allowing it to stand. And make sure that it doesn't rise in an unacceptable fashion that is a proper practice for evacuation or pulling a vacuum on a system. Some people will use the term dehydration along with evacuation and that's just specifically a term used for the drying of the system.

That's part of pulling a vacuum, because when you pull a vacuum, you pull it below the boiling point of the water and you're actually boiling water out of the system. So one of the functions of pulling a vacuum is dehydration, removing the moisture from the system. One thing that comes up with the EPA is some people will use an exception that you are allowed to use nitrogen along with a trace amount of refrigerant in order to do electronic leak detection. But the EPA does not allow you to take nitrogen and put it on top of an existing refrigerant charge as an excuse for intentionally venting.

You are able to put in a small amount of refrigerant and then pressurize it up in order to do an electronic leak. Detection, because your electronic leak detector only reacts to refrigerant and not nitrogen, that is an allowable usage, but it's only for the purpose of leak detection, not for the purpose of venting again we're not a to vent any of these controlled refrigerants based on the EPA regulations. Not again, that's it! That's it! For this part, just some common things that come up in the exam, some important things to know do more studying, based on what your instructors, given you or your guides that you got from whatever organization you're going to for your guide. But again I recommend ESCO or mainstream.

They both have nice guides that you can follow. Keep in mind, make sure you using the latest information, because a lot of these regulations are changing very quickly. It's very possible that when you see this video, it may be a little bit older and we don't. We want to make sure that you're keeping up with the latest information.

That's why I'm trying to cover pretty general things that just help as a review to prepare. You for the exam or just as a refresher if it's been a while thanks for watching we'll catch you on the next one, which will be our review of the type 1 certification. So low pressure system get you in the next one.