Compressed Natural Gas (CNG) Vehicle Maintenance Facility Modifications Webinar (Text Version)

This is a text version of the video for Compressed Natural Gas (CNG) Vehicle Maintenance Facility Modifications Webinar presented on Dec. 7, 2017.

Sandra: I'm Sandra Loi from the National Renewable Energy Laboratory. Today's webinar will focus on the recently released Compressed Natural Gas or CNG Vehicle Facility Modifications Handbook. The handbook covers primary considerations for developing a CNG vehicle maintenance facility, and today's webinar will offer an opportunity to hear about topics included within the handbook, as well as how you might put this guidance to use. This first of its kind document can greatly improve understanding and safety surrounding CNG maintenance facility design.

We have several speakers on today's webinar. Before we get started and I introduce our speakers, I'd like to go over a few items, so you know how to participate in today's webinar.

As noted at the start of the webinar, all attendees are in listen only mode, and will remain so through the entirety of the webinar. When you logged into today's webinar, you have the option to listen in using your computer speaker system or over the telephone. Please select one or the other. Audio or dial in information can be found on your control panel. We will be hosting a question and answer session at the conclusion of all today's presentations. We encourage you to submit questions as the presentations are taking place. You can do so by typing your question into the questions box in your control panel. We will collect these and address them during the question and answer session.

We are recording today's webinar, and a link to the recording will be posted within ten days on the Clean Cities website.

Now I'd like to go ahead and introduce today's agenda and our speakers. Mr. Dennis Smith will kick off today's webinar. Dennis is the National Clean Cities Director and Technology Integration manager for DOE's Vehicle Technologies Office. In addition to coordinating the efforts of nearly 100 designated Clean Cities Coalitions around the country, his duties include working closely with truck and auto manufacturers, fuel providers, state and regional governments, national laboratories, public safety officials, and other key stakeholders, to expand the use of alternative fuels and energy-saving technologies and practices in the transportation sector.

Next, we'll hear from Dr. Myra Blaylock from Sandia National Labs, who will cover the basic properties of CNG and indoor CNG release modeling. Dr. Blaylock has been a senior member of technical staff at Sandia National Labs for five years in the thermal fluid sciences and engineering department. She has run computational fluid dynamics simulations for risk analysis of natural gas releases and NGV maintenance facilities. She received her PhD in mechanical engineering from the University of California Davis, where she used CFD to analyze active flow control for wind turbine blades.

Following Dr. Blaylock, Robert Coale and Jarrod Kohout from Gladstein, Neandross & Associates will provide an overview of the handbook. Mr. Coale has an exceptionally strong background in CNG fuel station design and maintenance facility modifications. He has over 50 years of experience in directing the engineering design construction, operations, and maintenance of industrial facilities, including CNG, LNG, and conventional fueling stations and energy recovery systems, and mineral recovery and processing plants. Mr. Coale has been responsible for the design and construction oversight of more than 30 alternative fuel infrastructure projects.

Mr. Kohout has extensive experience managing projects, ranging from alternative fuel feasibility and market assessments to technology commercialization support. His alternative fuel experience includes fleet analysis, technology evaluations and comparisons, test plan development, emissions testing, and infrastructure sizing analysis and costing.

Finally, John Gonzales, senior engineer, and Kay Kelly, project leader from the National Renewable Energy Laboratory, will round out the webinar with guidance on working with code officials.

Without further ado, I'd like to pass things over to Mr. Dennis Smith. Dennis, you may begin.

Dennis: Okay. Thanks, Sandra. I'm calling from our Energy Department headquarters office in Washington, DC. Thanks, everybody, for joining us. I'm particularly excited about this presentation today because if you look back at the topics that have been requested or the things that our Clean Cities coalitions have told us over the years, one of the things they've repeatedly said is very important is can we get some best practices or a handbook or guidance on what needs to be thought of when people are considering installing natural gas vehicle equipment in either facilities where they work on the vehicles, or they're stored, or whatever. It's very dependent on the facility that it's going into, the age of the facility, when it was built, and that sort of thing. But it's always been a source of great confusion, and probably one of the most requested topics that we've had.

So the labs worked together on the document that you're going to go through today, but then also, this past year we've made two awards for some training projects that you're going to be hearing more about in the months to come to look at how you plan for gaseous fuel conversions, and to introduce them into garages or into design garages. That's covered in here. We've got two projects, one with the Gas Technology Institute, one with Marathon Technical Services. So we ask you to pay attention to that.

In part, they used the guidance you're going to hear about today to prepare and work on those programs, and since everything is so dependent on the facility itself, those trainings are going to also include walk through tours of some facilities so the students can see how things were done, or what lessons were learned, on a case by case basis, because so much of this is case by case. We're going to give you the best practices, but in many situations, the real answer is it depends on your situation.

So again, thanks for joining us. We agree that this is a very important topic, and hopefully, you'll get a lot out of it today, and you'll find this new handbook to be very useful. Thank you.

Myra: I can begin.

Sandra: Dr. Blaylock, you're up.

Myra: All right. I'm next. Hi. I'm Myra Blaylock, and like they said, I'm from Sandia National Labs out here in Livermore, California. And I'm going to be giving an overview of our project that looks at modeling leaks in maintenance facilities. So – okay. So our – what Sandia is doing, so our role in all this, and why Sandia is involved, is to help improve the codes and standards for gaseous fuel maintenance facility design, and kind of keep up with the technology advances.

And it comes in three parts. The first part is the quantitative risk assessment, and with that, we methodically and quantitatively look at – figure out what are the most important scenarios for the codes and standards and for safety, and once we have those scenarios, we want to model them. And the modeling comes into kind of two parts. First is the leak characteristics, like what is the leak going to look like, and so we have a code that can kind of figure out the velocities and the amounts of gas and the time it takes for it to leak out.

And then we put those into the actual computational fluid dynamics modeling to see what happens to the gas after it is released into the air. And both of the models are connected to some experimental validation that we're doing also. Mostly, that's for LNG, but for some CNG also, and that's needed as well. Next slide.

So taking a step back, I wanted to go over some CNG properties that's kind of the basics, and why it's different from the traditional gasoline cars. And the most important one of this is the density of CNG, and that it's lighter than air. So if you're going to have a leak, it's actually going to rise into the air instead of pool on the floor. What's important for me in my modeling is the flammability range. So I need to have a concentration that's at least 5 percent in the air, so 5 percent of the natural gas versus 95 percent air, before it will catch fire, and so that's an important thing to keep in mind when we're looking at the safety of a leak.

We've looked at two different typical tank sizes in our modeling, the light duty and the heavy duty, and the light duty is about 350 liters, and the heavy duty I think is slightly less than 700 liters. It's – that's what we model, but we have safety factors in there, so those are probably a little bit big, but that gives you a ballpark idea. And usually capped at the 250 bar pressure.

And then the final component of the modeling is like what is actually going to be a typical leak. The most likely case is going to be a crack in the pipe or the hose, and if the rest of the system is intact, and the valve is closed to the tank, when this happens, you're probably only going to have about three liters of fuel that's released. On the other side of that is the worst case scenario, which is you're going to have a valve that's connected to a full tank fail open, and so that entire tank is going to blow down and empty into the air. Okay. Next slide.

So kind of walking you through our process, the very first thing we want to do is the quantitative risk assessment side, where we do have a HAZOP or hazard and operability study to find out what are the most important scenarios that we want to look at. And this involves having a room full of experts sitting down and talking about it and putting weights on each of the scenarios, so it very methodically figures out which ones are the most important ones.

An example of this is what – kind of rose to the surface is one of the first ones that we modeled, was the situation that is talked about or is addressed with the NFPA 30A code, which restrictions ignition sources with anything that is 18 inches – or anywhere 18 inches from the ceiling. But basically, this number came from the codes and standards for gasoline, and it's 18 inches from the floor, and it's a great place to start, but now that we know a little bit more about natural gas and how it acts, we might need to go back and rethink this, because our modeling showed that it didn't just float up to the ceiling and build up until it got to the flammable range. There's actually a plume of flammable mass between wherever the leak is and the ceiling, and also with the right situation, you can get the flammable mass below this 18 inches as well. So next slide.

So again, we want to know exactly what – how much fuel is going into the air, and so we have a in house code that we have – just the network flow modeling. And so for this, we take into account all of the tank size, the tank pressure, the pipes, the valves, and what we think the leak size is going to be. And from that, we can find out what is going to be the mass flow rate of the leak, and then also the temperature of the leak, and then the pressure in the tank, and how long the pressure is going to get back to the atmospheric pressure, and that's the blow down time, is what we call that.

And we put all of this information into our CFD modeling to see what happens when the leak hits the air, and so that's next slide.

And then for that, we've looked at several different scenarios, two different sizes of garages, kind of light duty, heavy duty, the leak locations and amounts, kind of like I said before, a typical leak or a worst case scenario leak. And we also wanted to answer questions like do the presence of beams in the ceiling make a difference? And we kind of – no surprises, or no anticipation here. We wanted – we did find that there wasn't really a significant difference, so you can have a maintenance facility with the ceiling beams in there, and it won't make it more dangerous.

The second – or the next thing we want to look at is what does the ventilation in the system or in the room do, and we found that with your typical five air changes per hour, you do definitely reduce the amount of flammable mass, but you don't get rid of it completely. So next slide.

And so this is going to be a movie – there it goes, good – of your most likely scenario case. So this is about the three liters of fuel releasing into the room, and for a fuel system line crack. You can probably play it again, maybe. Yeah. Great. And you can – maybe. You can see that it actually does stay close to the – the white region is where the flammable mass is, and you can – it stays close to where the leak source is, and then kind of dissipates and becomes less than that five percent, as the time goes on. And the leak gets slower and dissipates. So that's done. You can go to the next slide.

Okay, and so this is probably the worst case scenario, and for this worst case scenario, like I said before, we were asking the question, can we have beams, and what does ventilation do? Right. And so this is going to be the full 700 liter tank emptying through a completely open like one inch valve, like a PTRD valve, and you can see there is a lot of white, so that's a lot of flammable mass. And then there's like a plane in the middle of my garage, so you can kind of see the concentrations there.

And then this is a case with ventilation, and so it is – the air is coming in to the left on the bottom and out to the right, so that's kind of why it's emptying from the right there. And then as the leak winds down, then you get only the white near the – near the release point, and then it kind of dissipates from the ceiling as well. So – and all of the leaks are usually within like a several minute – like you only have flammable mass for like maybe five to ten minutes total, and then it dissipates, especially if you have ventilation.

So final slide here, sometimes – so it's really nice to see exactly what's going to happen with the modeling of the CFD, like where the gas is going to go, and how it's going to react with the ventilation, but sometimes, you just need to answer the question, is there going to be flammable mass or not? And for that, we have a different tool, which is a analytical solution of the plume. We use the Burch plume model. And within minutes, we can see if there is a plume that has a concentration that's in the flammable range, where the CFD takes like several weeks to get the video that you just saw.

And so a case for this is important was the International Fire Code has a new regulation where if you depressurize your tank to 250 psi before entering the garages, you have a different set of criteria you need for your maintenance facility that's less stringent. And so we wanted to see if this depressurizing the bank completely got rid of the flammable mass, or if it just reduced it. And from my calculations with this plume model, I saw that actually, yes, there is a little bit of flammable mass, a small plume, but again, like lasts only a couple of minutes, or probably less than a minute. And so with the – and that is like a very quick answer, if you just want to know, yes or no, is something there.

I think that is it, and then I think – oh, and we have reports and movies, and then we're going to have a new final report coming out very soon, and that can all be found at the And there is my email if you have any questions after this, but I think there will also be questions at the time for questions at the end of the webinar today. So thank you.

Sandra: Thank you, Myra. Okay. Bob and Jarrod?

Jarrod: This is Jarrod. Oh, sorry.

Bob: Jarrod, go ahead.

Sandra: Go ahead.

Jarrod: I'll start off the presentation and hand it over to my colleague Bob. First off, thank you for the introduction and to the NREL team for providing the opportunity to participate in the developing of the handbook. The presentation that we're going to go through provides a summary of the details, and we encourage the audience to download the handbook as a resource. The photos within the presentation and handbook are generic, but they do illustrate actual conditions that we have encountered in the field.

GNA has many years of practical experience in the assessment and design of CNG maintenance facilities, and this [audio glitch] industry stakeholders. Next slide.

The handbook was specifically [audio glitch] – the handbook was specifically developed [audio glitch] MGM propane _____ specific requirements are met [audio glitch]. The handbook was developed so the three primary codes [audio glitch] facility design, the National Fire Protection Association, the International Mechanical Code, and the International Fire Code. The codes are periodically updated, so it is important to confirm that the latest version is being used during the design process.

Fuel by nature introduces safety hazards, and the equipment and protocols necessary to ensure safety in a CNG maintenance facility differ from those necessary for providing protection against liquid fuels, such as gasoline and diesel.

Dennis: Jarrod, this is Dennis Smith. I don't know if maybe you might be on a portable or a battery phone or something, but it's cutting in and out a lot, and we're missing some of your words. I don't know if there's another phone you can jump on.

Jarrod: Bob?

Bob: Yeah, this is Bob Coale with GNA. Can you guys hear me okay? Maybe I can pick up where Jarrod's having trouble with his phone.

Sandra: It sounds good, Bob. Thank you.

Bob: Okay. Well, as Jarrod pointed out, there are the codes that you can see here on the slide that are in force. This particular handbook was developed using the 2015 NFPA 30A. There is a new edition NFPA 30A to be published in 2018, and from the preliminary views, we've seen some changes within that document, so it's important to have a look before you cast your designs in stone. Next slide, please.

The authority having jurisdiction, which is generally the fire department, is an extremely important actor in the development of designs for maintenance garages. The codes are intentionally written somewhat loosely, because the code writers know that the – each facility is different, and not all facilities can comply with a specific code. So given that flexibility, the AHJ will often be able to allow some designs that are not necessarily cast in stone in the codes. Okay? Next one.

Two important issues that are in the handbook and in the codes themselves are the distinction between a major repair garage and a minor repair garage. It's very important for users to go through those definitions and look carefully to see whether they fall into one or the other. It's important to know that if you have any of the activities that occur in a major repair garage, the entire area needs to be classified that way. For that reason, sometimes it's useful to segregate the minor repair activities from the major repair activities, so that you don't have to modify the entire garage. Next slide.

That's pretty much what I just said, so let's go on to the next one.

There are five elements that need to be considered in the design of a maintenance garage modification, and those are listed here. Each garage will have a different set of criteria, depending upon its design and age and use, so it's important that each of these elements be considered when you're evaluating what needs to be done. Next slide.

As pointed out earlier, methane is lighter than air, and these pictures show potential paths of migration. You'll notice that holes in the walls or ceilings are potential spaces for methane to escape from a garage into another, so it's necessary to keep these things sealed. Next slide.

Here are some additional areas. You'll notice on the bottom left that there's a stairway that is not controlled, so if there's a leak, it could go up into an unprotected area. Similarly, the open doorways or gaps between structural members of the roof might provide a path for migration. Next slide.

As pointed out earlier, ventilation is an important means of preventing the explosive concentrations. The rates of ventilation are somewhat confusing, because the two different codes specify different rates. One says four air changes per hour, one says five air changes per hour. So it's important to work with the AHJ to determine which level needs to be done. The ventilation I think is probably the most important means of diluting the plume of combustible gas, and therefore rendering the area safe. Next slide.

This talks again about the two different codes. The International Fire Code requires five air changes, NFPA 30 four air changes. Next slide.

These items on this slide indicate the variables that are involved with ventilation design. Some people in the Southwest where it's hot all year just leave all the doors open all the time and the fans running full time. If you're located in Bangor, Maine, you can't do that, so your design for ventilation will be a lot different, because the climate is different. Also, the type of work that's done in there, if there's welding going on that produces fumes that need to be ventilated as well, that's something to be considered. Next slide.

These pictures show several different types of ventilation that are possible. In the upper right is a upblast roof fan, which is probably the most common. The lower left shows some ground mounted ventilation fans, because the roof isn't strong enough to hold the fans that are necessary. And then you can see ducting or direct evacuation in the other two photos on this slide. Next slide, please.

Makeup air is most frequently provided by opening garage doors. Sometimes security issues prevent the garage doors from being open during times of non-occupation. That can be solved by putting some screen along the bottom. Otherwise, in-wall louvers or sidewall fans also provide makeup air. Next slide.

These are the strategies that you need to look at to determine what is the best system for your particular operation: cost, climate, controls. You'll notice on the bottom picture there, and Myra pointed this out earlier, that there are no ignitions points within the pockets that are shown here, so it's not necessarily to ventilate each of those pockets completely. It's only necessary to ventilate areas that are – that contain possible sources of ignition. Next slide, please.

Space heating is one of the requirements to eliminate points of ignition, either from high surface temperature or open flames or electric sparks. Most older garages, the space heating is non-compliant, and therefore needs to be reviewed and replaced. Next slide.

It was pointed out earlier that the NFPA 30 requires that the space between 18 inches of the ceiling be classified as class I, division 2 electrical classification. This is not entirely true, because if the – if the facility is classified as a minor repair garage, then that's not necessary to have that area classified. And currently, the regulation says that if the facility has four air changes an hour, a ventilation – a permanent ventilation, it's not necessary to have that area within the ceiling classified. The AHJ may differ with that, and that's something that you have to work within. Next slide.

These are just photographs of some of the types of appliances and equipment within a garage that may need to be reviewed for compliance, whether they're sparking or non-sparking. Next slide.

Low voltage requirements as shown on the left there is a – an issue that you have to work with the AHJ. Generally, these are considered non-sparking, but it's up to that gentleman. Also, you'll notice on the right the magnitude of conduits here, that rather than relocating all of these, if you can provide seal-offs with AHJ approval, that's a far cheaper way to go. Next slide.

Methane detection and control systems are generally required by the AHJ, as pointed out in the regulations. It's not essential that they be there, but it's difficult to have the AHJ not approve them. Also, insurance underwriters may not permit the facility to not have detection systems. And for the cost involved, it's generally a very safe thing to do for your people. The bottom elements on this slide shows what the methane detection control systems offer. Next slide, please.

We've found in our work, looking at the bottom bullet there, that NFPA suggests that a 25 percent lower flammability limit be the trigger point for actions that are initiated by the detection system. We've found that if you use two levels, 20 percent and 40 percent, which must be approved by the AHJ, but it offers a lot of – a lot more protection against nuisance alarms and callouts, and provides actually just as much protection as is probably available from the 25 percent level. Next slide, please.

There are several different types of detectors that are available. There's the catalytic bead, infrared, and the handheld device. We don't recommend the catalytic bead, because they have elements that burn out after a while, and generally, because of their location, are difficult to maintain.

Open path infrared detectors are available, and these are generally used in large outdoor facilities. Using them indoors where exhaust from the vehicle is involved may cause them to not function properly.

We also recommend that handheld detectors be used by mechanics when they're working on natural gas vehicles prior to initiating your operation, although the smell of natural gas is generally as good an indicator as the handheld detector. Next slide, please.

There are a number of factors that affect the cost. As you can see here, typical cost may run between $40,000.00 and $80,000.00 per bay. Generally, the older the facility, the more it's going to cost, because it doesn't have the necessary upgrades in terms of ventilation and other facilities that newer ones have. So it's important to make sure that the management is aware of how much it might cost and budgets are in place before you start moving ahead with actually doing the work. Next slide, please.

The timeline here will certainly vary depending upon the complexity and size of the system. The main intent of this slide is to show the activities that will be required from the initial start of the initial assessment of the garage, all the way through to training and startup. Next slide, please.

The summary – in summary, this handbook is not intended to provide design criteria for design of the facility, but rather to alert the users, maintenance garage supervisors, and other people what needs to be done and how to go about doing it. And I think this slide pretty well covers that. These are all – all of the slides that we presented are modified – are amplified in the handbook when you get a chance for it, and you can see where the book is available from. And that concludes what I have to say.

Sandra: Thank you, Bob. John?

John: Thank you, everyone, and Bob, thank you for those good pieces of information. My presentation is just going to kind of wrap this up and put a bow on it. If we can, Kay, to the next slide. It's really understanding the building code, the roles and the responsibilities. Bob had spoke a lot about this. I just want to go over and highlight these.

There are multiple codes and standards agencies that facilities and facilities managers will have to work with, and that's really where the development of the codes comes from, because there are multiple codes that might fall into the jurisdiction of the building that you're working on, so you want to kind of do your due diligence and your research there.

Also, work with your local governing bodies, the folks that do the permits, those different pieces, to figure out which code you do need to work with. And then critical is the AHJ. Ensure that you are working with their current code. What we have found, and I think Bob alluded to, that you might have a current code, but they might not be using that. So you need to work with your AHJ to find out what is the current code that they are operating from.

And that is where this next slide comes in, the key piece to us, and we can't emphasize it enough. Work early and often with your AHJ, the authority having jurisdiction. In most cases, this would be the fire marshal, but it might be some other city official. But work with them early and often, because you need to get their buy-in, for one. That's the first thing. And then two is understanding what code they're working with, and making sure that they understand the work that you are going to be doing in that facility. That will help prevent any long lead times trying to do the upgrades to these buildings that you're looking forward to doing.

We want to make sure that everybody knows that there's a good network of Clean Cities coalitions throughout the country. We have nearly 100 coordinators, and many of them are very well-versed in working on these different situations in these buildings. If they are not, they have good contacts to help you. They're a great resource for you. Feel free to reach out to them, and you can find that on the website. We've got that listed there.

And we're also available from a technical assistance standpoint. We do have a lot of information that we can provide. We're the ones that helped work with GNA and others to put this guide together. So feel free to reach out to us as well if you have any questions. We can help you there, too. That's a resource that we provide. But once again, just refreshing that you want to make sure to work out early and often with your AHJs to help provide information that will help guide you through the process, and also minimize the issues that you might foresee or come through when you're building a facility that would operate natural gas vehicles. That's really the extent of mine, Sandra.

Sandra: Great. Thank you, John. Thank you to all of our presenters today. I'm not seeing any questions at the moment, but don't be shy. Go ahead, and you still have time to type in a question. You can do so in your control panel, in the questions box. And I had received a question at the beginning. Someone was asking for access to the handbook. We will send out a follow-up note to all of those who attended today, and we will include the link to the PDF. And as I had mentioned at the beginning, we are recording today's webinar, and we will be posting that link, and we can also share that as well with you all, so you can access it afterwards to share with your constituents or to refresh yourself on what was covered today.

We'll just give it a moment for any questions.

Dennis: Yeah, Sandra, this is Dennis. I've got some things to help with the wrap-up here.

Sandra: Sure.

Dennis: And Bob touched on some of this with his GNA slides. But in addition to the electronic equipment and the sensors and different things that will go into the design considerations for what the upgrades might need to include, you need to really also consider how important the operational procedures are. In other words, you can do a lot to minimize the risk by making sure that people are trained, and to take a look at how the work is being done in the facilities. For instance, I know a number of installations around the country have had good luck working with their fire officials to schedule certain routine maintenance for summertime, when the doors and windows can be open, as opposed to trying to do that stuff in the winter, when the heaters are going, and everything's closed up. So a lot of these things to minimize risk can be done by just being smart about your operating procedures.

And then certainly you can't underestimate the value and the importance of training your people on all of these new things when they're installed, or in the design process, so they know how the safety equipment works, where it's located, how to maintain it, and then also how that interacts with the vehicles when it comes in.

And then it's not just the buildings. Some of it has to do with how you prepare the vehicles before you even bring them into the buildings, so that if you need to defuel it so that there's not a full tank of fuel when you're going to do some maintenance, those are all considerations, again, with the operations of how you plan your work, and also just your daily operations that are going to be different than they might be with the liquid fuels.

Sandra: Great. Thank you, Dennis. We've had a few questions come in. I'm going to go ahead and start going through those. One of the first ones I have here is I guess a question on whether there are grants are funding for modifications of facilities. So Dennis, I think from the federal side, can you give a perspective from the federal side, and then maybe, Bob, if there's – if you've ever had any projects in your experience where folks were able to get funding assistance for upgrades?

Dennis: Yeah, from the Energy Department's aspect, I'm not currently aware of any grants or assistance. Normally, where we've seen that be done through any federal funding is if they're transit agencies or others that have to upgrade facilities, then sometimes that cost can be rolled in, just like it would be for if they build a new garage facility. But I'm not aware of a specific pot of grant funding available for that right now. From time to time, DOT Federal Transit Administration has had certain programs for that, but not aware of anything for other fleets right now.

Bob: GNA has prepared grant applications for groups that want to change from diesel and gasoline to natural gas, and the funding is largely to support the purchase of new vehicles, but very often, they can tack on a garage maintenance rider on that funding application, because without the proper garage modifications, the fleet is no good to them.

Sandra: Okay. Thank you. Another question here, probably for Myra, is any of the plume research from Myra incorporated in new – is any of the plume research from Myra incorporated into the new handbook yet?

Myra: I would say that it's just mostly looking at, like they were saying, like looking at what's happening at the ceilings, and like whether or not it's going to get caught in the pockets, and things like that. So I would say yes in the sense that the modeling did show that it – that it – the natural gas did what we expected it to do, which is like go up to the ceiling and –

Bob: I think it's –

Myra: – kind of there. Go ahead.

Bob: I think it's very important to point out that releases of the massive type that Myra talked about are exceedingly rare.

Myra: Really, really rare. That's – yeah. I – good point. That was – we wanted to look at a worst case scenario, but the chances of this happening were really, really small.

Bob: Yeah.

Myra: Yeah. Good point.

Sandra: Great. Thank you. Another question, any cases of private partnership with public to receive tax credits as a result maybe of those modifications? I guess I'm not aware of any tax credits that would be applicable to the building. Most of kind of the tax implications are associated with the vehicles, again, as Bob pointed out, the vehicle or the station. And as we've pointed out, that kind of goes hand in hand. If you're going to have a vehicle, they do need to be maintained somewhere, so you do need to do those things in tandem.

Then another question, are dates in place for compliance by a facility, where there's dates that they have to be in compliance? So Bob, maybe that's a question for you. I'm wondering if that's getting at can you buy the vehicles before the garage is modified?

Bob: Technically not. In order to maintain a vehicle, CNG vehicle indoors, the garage must be compliant. Sometimes, if the AHJ knows that you're in the process of modifying the garage and your fleet is starting to come in from new orders, they will allow you to go ahead. But really, you need to have the garage in compliance before you have your fleet, and logistically, that becomes difficult sometimes. Some owners will contract maintenance offsite, and depending upon the weather and conditions, they can do maintenance out of doors, rather than taking them inside. But it's a tricky issue that needs to be worked out with the AHJ.

Sandra: Okay. Thank you, Bob. So question, any information on facilities for hydrogen fueled vehicles? You know, something similar is being put together, other resources?

Myra: Oh, it's the NFPA 2 instead of NFPA 30A which has the codes and standards for that, but I think they're similar. Usually, there's a lot of overlap between the two different codes. Can you ask the question again? I don't think I'm answering it directly.

Sandra: It was basically if there's information on facilities – I guess for requirements for facilities for maintenance of hydrogen fueled vehicles. That's how I'm interpreting it.

Myra: Right. Anyone else can jump in, but – yeah. Go ahead.

Dennis: I was going to say, you might want to add that the two training projects that I mentioned in my introduction, one that's going to be presented by the Gas Technology Institute, and also the Marathon Technical Services, those were broader in that they're considering other gaseous fuels, like hydrogen, and propane as well, because they're going to behave a little differently and have different considerations. So those two training projects will touch on those fuels, and I guess I'd just tell everybody to stand by. They're currently working on the curriculum, and identifying the locations to take people on the site tours, so they're not quite ready to announce all the dates and the locations for that, but it will be coming up and you'll be hearing about that in the months ahead. So there will be, yes, some hydrogen information included there.

Myra: NFPA 30A has some small sections related to hydrogen. Many of the safety requirements are similar to natural gas, because the fuels behave similarly. Of course, the explosive range for hydrogen is a lot different, and so those – that needs to be taken in account.

Sandra: Okay. I'm not seeing any additional questions. If you have a question, we still have about ten minutes until the end of the webinar. Feel free to type in your question in your questions box. If any of our presenters have any other thoughts or anything they wanted to add as we're waiting possibly for another question, just feel free to jump in.

Okay, well, I'm not seeing any additional questions, and not hearing any other thoughts, so I'm going to go ahead and wrap up for today. I wanted to thank everyone for participating. Thank you to all of our speakers for all of the information. We really appreciate you making time to be here with all of us. Thank you to our attendees. And as I said, we're recording today's webinar. We will do a follow-up notice and include a link to that as well as a link to the handbook. If you need any additional information, feel free to reach out to myself, Sandra Loi, and I can direct you to any of our presenters who were here with us today. Have a wonderful week, and thank you again.