In our seminar  Residential Ventilation in a rural setting the other night these where some of the comments.

 

When do you Ventilate?

 

Where do you Ventilate?

 

Why do you Ventilate?

 

Remembering for every action we make on the fire ground there will be a reaction. Do you do a vertical or horizontal vent hole. And where?

 

One of the things that stuck out in my mind was this and makes perfect sense when you think about it is.

 

The most important question up here is why are you venting. For Fire or Life.

We vent for fire because we want the fire to do what we want it to do and go where we want it to go.

We vent for life by taking a window and doing a vent-enter search for a suspected or known victim.

This was the commit: If you do not know why your going to vent then you most-likely shouldn't vent at all.

If we vent in the wrong spot by taking a window for the sake of taking a window we will bring the fire right to us. So if we just had a room and content fire; well now we have a whole structure fire. If we have fire blowing out the roof already is there really any reason to put a guy on the roof?

This was just some of the comments made. If any organization is going to put on a 3 hour seminar I would recommend this one.

 

Views: 932

Reply to This

Replies to This Discussion

My remark towards you was not meant as criticism. Just pointing out how the discussion tends to go. Especially when PPV is concerned.

I agree their is a lot of confusion about flashover. It occurs during earlier stage of fire; probably prior to FD arrival. Too many in the fire service describe any sudden flame development as flashover. If it happens because air is introduced it is not flashover; it is more of a backdraft. Both events are happening much quicker in terms of timeline of fire development these days.

We also take windows from interior when appropriate. But all horizontal ventilation must be evaluated before attempting, whether from inside or outside. Poorly coordinated venting will not improve conditions. It is a very difficult thing to train on. Fireground experience is the best way to learn and even that can take years to master. Plus the majority of us, with very few exceptions are not doing a lot of fire duty.

I'm new to this site but sharing of experiences is a great tool for learning. That includes successes and failures.

Staffing is indeed critical and we are going in the wrong direction (through no fault of our own). The response I get for a structural fire is about as good as it gets. Many departments can turn out fast or turn out a lot of personnel but not many can do both. Agressive interior attack has to have sufficient staffing in order to be done properly and consistent with safety. And I don't believe anyone should try to do more than that. Of course, if hoseline is delayed awaiting staffing, ventilation (at least in immediate fire area) would also have to be delayed. No clearing of windows just because we want to do something.

Some of the things I've seen, heard and read about make me real leery of live burn training. Some members and or departments just aren't able to do it safely. It's a definite "Catch-22" situation.

I also enjoy the discussion. Wish more would jump in.

I am starting to wonder if my dept. should be worrying about ventilation at all.  I understand now how many people it takes to ventilate properly.  We have a small town that does not take long to get to one side or the other.  But we all have to drive to the station, so response times are a little longer, but not too long.  I see the problem being lack of man power.  We send an engine with a minimum of four but with only two interior people, and one of those has to grab the hydrant.  That leaves an officer or senior man to do the size up and an engineer.  More may show up but maybe not.  We can call for help from the neighboring towns but they are twenty miles away, too long for a coordinated attack.  If a hose team is three and a roof team is three we are way behind the eight ball.  Should we be concentrating on hose ops instead?  I heard an officer in a neighboring town say that we volunteers don't need vertical ventilation because we have a PPV fan now. 

If I was working with that few personnel I would definitely concentrate on hoseline ops. If you vent before extinguishing, the fire could grow exponentially while you do it. You may then have a fire condition that can't be attacked safely by one hoseline. You may very well lose the building. If you attack the fire with an interior hoseline, you would have to do it with two people. Two would have to remain outside for RIT purposes. (Two people to rescue two people is not all that realistic but it's better than nothing and meets two in two out standard.) I would suggest a cautious line advance with constant communication with outside team. One properly positioned and operated line can extinguish a lot of fire. For an advanced fire or one at which all occupants are accounted for you may not go in at all. Apply risk vs reward principal. There are things we can do and there are things we can't do. That's just the way it is.

As far as that neighboring officer: Those PPV fans have major limitations on their usage. PPV proponents all admit this. There are many situations where they will tell you that fans are not appropriate. A sufficiently sized roof vent and application of water are both always appropriate. Vertical ventilation DIRECTLY OVER THE FIRE is the second best tactic we have (after water).

Stay Safe.

As far as PPV goes, it's been exhaustively debated in the fire service for a lot of years. Here are the vital points that supportes of PPV have never explained to my satisfaction:

 

I guess the question is as to what you have heard and why do the questions still stick out to meet your satisfaction?

 

1) They say never start a fan AFTER firefighters have entered the structure. Would this be detrimental to firefighters in full PPE? If so, what does it mean for UNPROTECTED civilian victims who may be present?

 

Depends on the defination of "they". I understand that a PPV fan should not be used to "find" a fire and perhaps that can be the basis to what is seen. There is also the issue of communication between what is seen between inside and outside. For instance if you have an interior team with little to no smoke and outside you see more smoke and perhaps intensifying, then that means you have fire somewhere....putting a fan in with people still inside can perhaps block off their egress, create a fire situation and so forth, putting personnel in jeopardy. Again this all depends upon the situation presented, so I don't know what more of a satisfaction to what you may be looking for.

 

As for civilians, when it comes to PPA....which does differ from PPV....there shouldn't be a victim between the fan and exhaust. That is also why the aspect of "just doing because we always have" is dangerous and shows why there should be more training when using mechanical ventilation.

 

2) They say fan use must be discontinued if smoke/heat/fire gases are seen exhausting out of entry point. Because fan is not being effective. Probably due to insufficient number or sixe of exhaust openings. If fire has been drawn to entry point, where else has it gone?

 

This is another aspect of PPA and essentially you already answered your own question. Using the entry way as a barometer, it comes down to understanding what is going on inside the structure. Most likely smoke/fire at the entry point means there is inadequate exhaust.

 

PPA, is really another tool that can be used, but needs to be traied on and learned to know when and how to properly use it. Yes, getting water to the fire is the best method overall, but doesn't mean that such tactics on ventilation are buk either....it depends upon the situation presented and resources available.

 

Personally, I see no issue of say and engine company showing up, having a guy get a fan started and ready to turn into the door, have another stretching a line, etc while waiting for other companies to arrive to meet 2 in 2 out. So really the question becomes something that is variable and I don't see any firm answer to meet an answer ro one's satisfaction. Frankly if you don't want to use PPA, then don't.....there are other tools out there and PPA is not always the best choice.

 

 

3) Once you apply all of the parameters for when PPV can be used, you realize it's only appropriate for a relatively small number of fires. Water is always appropriate and accomplishes all of the things that PPV does.

 

Depends upon what and when you are using this. It seems that you may be confusing PPV with PPA. There are differences.

I am starting to wonder if my dept. should be worrying about ventilation at all.........We send an engine with a minimum of four but with only two interior people, and one of those has to grab the hydrant.

 

When it comes to a scene, the command and tactical decisions are based off of what is presented to you and what you have in resources to meet them. If you don't have enough personnel on scene t pull lines, vent and so forth, you need to concentrate on what you CAN do. Given that you mention that you roll up with a 4 man crew, but only 2 are interior....you are behind the curve already and frankly your tactics are moreless limited to exterior operations.

 

Even if every person was interior ops qualified, there would be no reason to be putting people at risk by trying to make an interior attack. Mathmetically it works for 2 in 2 out....realistically it doesn't, so it shouldn't really be attempted. (unless there is a chance of savin a savable life).

 

Given the circumstances which you face it is up to your guys to size up and evaluate on what can be done as opposed to what others say to concentrate on.

 

Should we be concentrating on hose ops instead? I heard an officer in a neighboring town say that we volunteers don't need vertical ventilation because we have a PPV fan now.

 

 

Foremost I would say concentrate on doing size ups and evaluations as to what you can accomplish. Working on hose operations for interior situations is useless if you won't arrive with enough personnel to effectively do that. Getting water on the fire will be your best option of taking care of the fire, but even that is determind on what you encounter and what you can do.

 

As for what some other officer says, all the more reason to concentrate on departmental training and not base thing of of someone elses....nor someone leses officer. They are not you and they are not on your dept, I would question such statements, because frankly they are BS. It is comments like that, tat do get FFs hurt and killed making such ultimatums and saying you don't need to do vertical vent because of PPV. PPV is another tool....that's it, there are other options to go to and a FF should be able to switch tasks as needed. A fan is by no means the overall answer and it is assinine to even make such a moronic statement.

You are correct. I should have specified what I meant; I am referring to PPA.

You say there shouldn't be a victim between fan and exhaust. The only way to know this would be to conduct a search, which is also subject to two in two out rules (unless life hazard is confirmed). So now you conduct a search, then place fans, then put water on fire? Too much time is wasted. Not to mention if you do all this and then find out that exhaust opening is not sufficiently sized. More wasted time. Time is not on our side; we can't afford to waste it.

Using the entry point as a "barometer" tells me that the fan usage is now on a trial and error basis. "Let's try it and see if it works." If it doesn't work the exhaust openings have to be enlarged, which uses up valuable time. Or PPA has to be discontinued entirely. And then what? Conventional interior attack with hoseline. But only if that's still even possible due to fire growth while all this time passed.

So I still have a problem with the time wasted when "Barometer" tells us that PPA is not appropriate, the fact that PPA is only appropriate at a small number of fires and the fact that you have to enter and search in absence of hoseline just to really know if parameters are met. I'd rather see tactics and training geared toward the faster results we get AT ALL FIRES with a fast stretch and a properly positioned and operating hoseline (including transitional attack when appropriate).

Those are the problems I would love to hear someone address. Telling me to get some training does not address those issues. Telling me not to use it if I don't like it does not address those issues. Telling me you've been to fires where it's worked great does not address those issues.

Jim, I have to agree with Crabbe here. It doesn't matter what a officer from some other department says. You and you team are the one's doing the work. You need to train on what your abilities are and know your limitations. You know what buildings are in your district. You know what tools you have at your disposal; so train on what will work for your department. Not on what the department down the road says.

You say there shouldn't be a victim between fan and exhaust. The only way to know this would be to conduct a search, which is also subject to two in two out rules (unless life hazard is confirmed). So now you conduct a search, then place fans, then put water on fire?

 

Depends on the sitution involved. You can roll up on a house fire and a family can confirm that everyone is out. The fire can be a room and contents in one area with potential victim in another. Perhaps the victim was seen in a window by bystanders etc.

 

So I still have a problem with the time wasted when "Barometer" tells us that PPA is not appropriate, the fact that PPA is only appropriate at a small number of fires and the fact that you have to enter and search in absence of hoseline just to really know if parameters are met.

 

If that is what you think is occurring then you are not doing it right. The aspect of a "barometer" is not to wait to see effectiveness, because that isn't the point. The purpose of PPA is to cool the structure by forcing heat from the fire out the exhaust, thus clearing up the area not involved in a fire. This would be a tactic for say a room and contents fire where the fire is kept within the room of orgin, while smoke and heat is decreased. Since this takes about a minute prior to making an entry with a hoseline, one can view the entryway to determine if PPA is being effective. Smoke or fire a the entryway means there is inadequate exhaust.

 

 

Now, I'm not an expert in PPA by any means, nor is it a primary tactic for us, but it is another tool we have trained on and have used. I would by no means sit here and preach this as some great tactic, nor will I condemn it because of lack of understanding.

 

If PPA is not something you choose a a tactic, then don't use it. You seem to come across here as though there are hard set rules for the use of PPA, like how you go into the issue with a potential victim, yet reality is not that at all. This is just another tactic that can be used.....but if choosing to use it, one should know how and when the applications are appropriate.

Let's consider the following:

1) PPA should not be used if their is a victim between fan and exhaust.

2) PPA should only be used when adequate exhaust is present.

3) PPA should only be used when location and extent of fire can be verified with some degree of certainty.

4) PPA should be discontinued if smoke/fire show at entry point.

5) PPA would not be effective if interior door to fire area was in closed position.

6) PPA should only be used for fire in free-burning stage of fire developement.

I've seen all of the above statements given by proponents of PPA. Are you telling me that those are NOT hard and fast rules. Because you later state that "one should know how and when the applications are appropriate". From everything I've come to understand about PPA, I will stick with the notion that there are indeed hard and fast rules for it's use.

So if we accept that there are rules, let's consider the following:

1) Quite often we just don't know the location (or presence) of victims. In these common cases a search prior to fan use is the only way to verify this. Any time we commit to an interior search we owe it to ourselves to get a charged line in place to protect that search team. So now we've got multiple members along with a charged line inside the structure. Seems to me we should just extinguish the fire with water immediately anf forget PPA.

2) I believe that in many homes (especially older ones) the available window openings will not be sufficient for PPA exhaust. So we would have to spend valuable manpower and even more valuable time enlarging openings. Seems like it would be more efficient to just extinguish the fire.

3) If we have to enter to search in order to determine location and extent of fire we should have a charged hoseline for protection ASAP. Seems like we should just extinguish fire immediately.

4) If fire/smoke show at entry point we have to discontinue fan use. Too much valuable time has been wasted and we have to extinguish fire without benefit of fans. We could have just done that immediately upon arrival. Whether we WAIT for it to happen or just react if and when it does happen, it is basically a trial and error scenario.("Hey, let's see if this works.")

Not to mention that if fire/smoke is showing at entry point it could very well now be present at other previously uninvolved areas. Counterproductive to say the least.

5) At many fires we will have to enter the building to determine status of interior doors. Once again, if we are committing to interior ops to determine if PPA is appropriate why not just immediaely extinguish fire.

6) Modern contents fires reach flashover point very quickly (as little as 3 1/2 minutes). Fires often have "darkened down" prior to our arrival. So PPA not appropriate.

What it comes down to is that at most fires we could extinguish fire with a properly positioned and operated hoseline in as little time as it takes to just determine if fans should be tried, not to mention the time it takes to be sure fans are even working effectively.

I don't doubt for a minute that PPA is entirely appropriate at fires meeting all the criteria for it's use. I do doubt that an outside survey will tell us conclusively that it's use is appropriate. I do reject the loss of time involved with many of the scenarios I've pointed out above. I do believe that if we stick to the rules there just aren't that many fires where it's appropriate.

Money, training opportunities and staffing are all at a premium in today's fire service. I would rather see all of those things dedicated to proper stretching and operation of hoselines (in low visibility conditions) as opposed to PPA. After that I would go to horizontal ventilation ahead of hoseline and sufficiently sized vertical ventilation directly over fire. These things are always appropriate and always work at every fire. Once we can all do those things proficiently we can look at PPA for the few fires where it's entirely appropriate.

I enjoy the debate and will gladly continue. I'd love to see my specific concerns addressed.

John, your reply was similar to many others in that you tell me I "don't understand" PPA, or I "shouldn't use it if I don't want to", or "it depends".

None of that really advances the debate.

Stay Safe.

Just want to add that the "rules" or "parameters" or "guidelines" from above come from proponents of PPA, most of whom are trainers of PPA with classes, websites and articles devoted to it.

 

John, your reply was similar to many others in that you tell me I "don't understand" PPA, or I "shouldn't use it if I don't want to", or "it depends".

 

So if we go back to how this aspect of the discussion originated, it was your use of the term PPV when referring to PPA and that your questions were not answered to your satisfaction. Of which I replied on the PPV aspect and differentiated between PPV and PPA. You then go on about your reservations of PPA and now seem to come across that answers still don't satisfy you. I'm thinking that no answer is going to reach your satisfaction because you have a closed mind to the tactic and that the only satisfying answer is what you want to hear.

 

 

So to break down these:

1) PPA should not be used if their is a victim between fan and exhaust.

 

Actually looking back, the issue is victim between fire and exhaust. So if you believe you have a victim in a bedroom and say fire is in the living room, you don't open the windows in the bedroom to create an exhaust....thus puttng the victim between fire and exhaust. If the victim is say in the living room and the fire is in a back bedroom, placing the fan between the victim and exhaust should cool that area and help clear away smoke because the fire is being vented out the exhaust.


2) PPA should only be used when adequate exhaust is present.

 

Yeah. You create the exhaust by opening up the opposite side of the structure. You can gather this information on a 360.....so if you only have a small window or door on the opposite side of the structure, PPA would not be a good tactic choice. Most residences do have exhaust points on opposing sides of the structure and the exhaust is created BEFORE turning the fan into the entry. Communication is essential at this step and the exhaust should be opened before turning the fan in.


3) PPA should only be used when location and extent of fire can be verified with some degree of certainty.

 

Yeah, it is called doing a size up. The size up, the available resources, and the situation will dictacte the command and tactical strategy. It isn't too tough to determine a room and contents fire from multiple rooms and floors involved.


4) PPA should be discontinued if smoke/fire show at entry point.

 

Not necessarily, it could just be a matter of taking out another window. Again it is about doing a size up.


5) PPA would not be effective if interior door to fire area was in closed position.

 

Why not? PPA can be used in an exposure structure by closing windws and exhaust points to raise the pressure inside the structure to prevent the fire from spreading. Same concept with an interior door to the fire room being closed. You introduce cooler air and raise the pressure outside the fire room, thus keeping the fire to the room of orgin.


6) PPA should only be used for fire in free-burning stage of fire developement

 

And at what point do most fire departments arrive on scene? For a fire, typically it is in the free burning stage.

 

1) Quite often we just don't know the location (or presence) of victims. In these common cases a search prior to fan use is the only way to verify this. Any time we commit to an interior search we owe it to ourselves to get a charged line in place to protect that search team. So now we've got multiple members along with a charged line inside the structure. Seems to me we should just extinguish the fire with water immediately anf forget PPA.

 

I'm all about ensuring a search is done on every fire, but it also depends upon what the situation is we are presented with. If pulling up on a scene and you have family outside confirming everyone is out and accounted for, it is a good bet there isn't a victim. There are those other times when bystanders report seeing someone in the window moments before, or perhaps knowing the location of say the nursery etc.

Staffing is another thing that will dictate your tactics. You are essentially looking at 4 people inside to perform what you are calling for. Say you roll up with two rigs with 6 people initially and you have to wait for backup rigs. You can still do a 360, pull lines, start a fan, bust out windows, turn the fan in, make your entry and do your search. You can clear smoke and gases away from the potential victims of the fire, ease visibility of rescuers, keep the fire contained, etc. Again, it is about sizeup.


2) I believe that in many homes (especially older ones) the available window openings will not be sufficient for PPA exhaust. So we would have to spend valuable manpower and even more valuable time enlarging openings. Seems like it would be more efficient to just extinguish the fire.

 

Where and what are you basing this off of? Again, this goes back to doing a 360. If you don't have enough exhaust, then PPA would not be a good tactic to choose. Why would you get hung up on the belief that you have to spend time enlarging openings? Bit of a stretch. That is why the tactic is another option, not the only solution.


3) If we have to enter to search in order to determine location and extent of fire we should have a charged hoseline for protection ASAP. Seems like we should just extinguish fire immediately.

 

You can't determine location and extent from doing a 360? If you have fire showing from the AB corner, on the second floor and nothing elsewhere, it is a pretty good bet you woud know the general location of the fire.


4) If fire/smoke show at entry point we have to discontinue fan use. Too much valuable time has been wasted and we have to extinguish fire without benefit of fans. We could have just done that immediately upon arrival. Whether we WAIT for it to happen or just react if and when it does happen, it is basically a trial and error scenario.("Hey, let's see if this works.")
Not to mention that if fire/smoke is showing at entry point it could very well now be present at other previously uninvolved areas. Counterproductive to say the least.

 

You are delving into generalities. There are many factors that determine the use of the PPA tactic. Staffing is the biggest factor, because if you don't have enough to go interior right away, then you shouldn't be going in right away. Stop making this out to be a be all, end all tactic.


5) At many fires we will have to enter the building to determine status of interior doors. Once again, if we are committing to interior ops to determine if PPA is appropriate why not just immediaely extinguish fire.

 

Again, go to point #5 above.


6) Modern contents fires reach flashover point very quickly (as little as 3 1/2 minutes). Fires often have "darkened down" prior to our arrival. So PPA not appropriate.

 

Why not? Say the fire is still contained to a back bedroom room of orgin. Doing a 360 you see the soot on the windows and they are the only windows blackened. Caller states they saw flames in the window before and now they are gone. That most likely means you still have heat in the room and the fire needs air. You will be venting it anyway, so you can still do PPA and can keep the fire contained to that room.

 

 

I really can't reiterrate enough that this is just another tactical option to use. It is by no means the be all, end all tactic and even the strongest proponents of PPA admit to that. Should it just be discarded because one may not personally agree to it? I don't think so. The situation presented, along with resources available, will dictate the tactical decisions. This just another option.

Overall I agree with John Murphy on this.  Basically it's back to the basics.  Your officers are the ones that should be deciding on how, when and where to vent (based on why).  If you have people willy nilly taking out windows then at best, it's free lancing and at worse someone is going to get hurt.

Every job is going to be different and tactics have to be adjusted for each situation.  For a R/C, unless it's relatively new construction, the fire will most likely auto ventilate out the window(s) of that room, in which case you're now as vented as you need to be.  For a fire throughout, most likely vertical vent. is what will work.

Of course it depends too on your manpower on arrival; can you send 2 or 3 men up to the roof, another 2 stretching to the front door, your officer walking a 360 and your operator securing a water supply?  Do you typically ladder the building as apparatus roll in? Can your command run the scene, timing your interior attack with outside ventilation?

Mostly I think if you're getting questions of why, where, how and when then your department needs to establish some guidelines (SOPs/SOGs) and train the officers better.  A big problem today is that, while houses burn hotter and faster, there are fewer of them doing so and the people that used to be good at reading smoke and understanding tactics are retiring out and new(er) officers just don't have the experience.  You might want to suggest to your command about getting some department time in at the nearest burn tower for some practice runs in seeing what works best under different scenarios.

As John C. pointed out, look for the sooted up or broken windows (newer double or triple paned may NOT break from the heat so there may not be any auto ventilation), that room is likely the point of origin and your attack will be to push towards that room.  A fully involved (one story) floor likely means vertical vent is going to be your best bet. Fully involved first floor (two story) means second floor horizontal may be a good bet.

Just remember, every opening you make is going to supply an air channel to the fire, including the door you make entry through; timing and experience is needed (or at the least, damn helpful).

We don't do PPA so I'm not dipping a foot into that discussion.

John,

You are correct in that I haven't always explained myself accurately and it is PPA to which I am responding. I do know the difference between PPA and PPV. I am not as closed minded as I may seem. I have stated that I believe there are times PPA is entirely appropriate. What I don't believe is that we can reliably ascertain which times are which. We often can't determine location of victims along with location and extent of fire from an outside survey and/or interviews. I don't believe outside survey alone is reliable enough. Much like the fan, it is just one tool. Quite often, we find interior conditions that are much different than what we expected to find.

In point one I again misspoke but it was a victim between fire and exhaust that I meant to address.

Point two was based on parameters given by people who train others in the use of PPA. Articles and websites have stated that the exhaust openings should be 1 1/2 -3 times the size of entry point. The front door to my house is 32"x80". Two of my bedrooms each have a single 30"x40" window. The other two each have two 30"x40" windows. Numbers like these are very common in my NYC suburb (and NYC) and I suspect they are very common nationwide. They don't come close to meeting the guidelines put forth. The point about enlarging the openings also comes from "experts" in this field. I agree that it is a stretch but it's not my stretch.

Point four may be the most vital of all. Because if we use the entry point as a "test" of conditions, we are really saying that we don't know when we start the fan whether it will help or hurt (spread fire/smoke to other uninvolved areas).

If it does spread smoke/fire to uninvolved areas it is not a "generality" ; it is a major tactical error.

Point six is also not from me but from an "expert" in the field. I will say that once a fire has "darkened down" all ventilation, PPA or not, can have severe negative consequences.

I am not on a crusade against PPA. I just don't see it being appropriate at many fires. I see it as a specialized tool and tactic. I would hope that every department that uses it understands the relatively limited opportunities to use it appropriately. I suspect many departments and or members do not fully understand. My concerns are all based on the parameters given by people who are recognized as experts in this field. When you consider all the limitations, I'm a little surprised anyone bothers with fan purchase and training.

I'd much rather see the limited money and training time available to the fire service used for basic firefighting skills that are appropriate at all fires. Things like fast entry and search. Locating and confining fire. Fast stretching and operation of hoselines. Vertical ventilation directly over fire. Controlled horizontal ventilation ahead of hoseline. I do understand that there are often staffing issues involved.

I also suspect that PPA is used as a crutch by some because they are not proficient at the above firefighting skills. These, of course, are the departments and or firefighters who will use PPA in an inappropriate manner.

Reply to Discussion

RSS

Find Members Fast


Or Name, Dept, Keyword
Invite Your Friends
Not a Member? Join Now

© 2024   Created by Firefighter Nation WebChief.   Powered by

Badges  |  Contact Firefighter Nation  |  Terms of Service