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7 March 2025
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Featured FRI Magazine article: High-rise firefighting written by Colin Deiner
The north wing of the new CCTV headquarters tower in downtown Beijing in 2009
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The fire on the 38-floor of the Meridian Plaza building in Philadelphia in 1991
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Clean up of the fire-damaged Munitoria building prior to blasting Photo credit: Jet Demolition
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In 2007 a seven-alarm fire broke out on the 17th floor of the Deutsche Bank building in New York, which spread in both directions, affecting a total of 10 floors. Firefighting was additionally hampered as the building did not have a functioning standpipe, forcing firefighters to raise hoses up from the street to combat the flames. 45 engine companies, 30 ladder companies, 3 rescue companies, 19 battalion chief units, 4 division chief's units and numerous other special and support units responded from the New York City Fire Department to combat the fire
Photo5: A high rise fire in Johannesburg; Photo credit: Etienne du Toit
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This week’s featured Fire and Rescue International magazine article is: High-rise firefighting written by Colin Deiner, Chief Director, Disaster Management and Fire Brigade Services, Western Cape Government (FRI Vol 3 no 3). We will be sharing more technical/research/tactical articles from Fire and Rescue International magazine on a weekly basis with our readers to assist in technology transfer. This will hopefully create an increased awareness, providing you with hands-on advice and guidance. All our magazines are available free of charge in PDF format on our website and online at ISSUU. We also provide all technical articles as a free download in our article archive on our website.
High-rise firefighting
By Colin Deiner, Chief Director, Disaster Management and Fire Brigade Services, Western Cape Government
On 23 February 1991, a fire is started on the 22nd floor of the 38-floor Meridian Plaza building in Philadelphia, Pennsylvania. It was later found that the fire originated in a pile of oil-soaked rags. A smoke detector on the 22nd floor detected the fire but due to poor coverage of the system, the fire had already spread significantly at this time.
Firefighting operations were severely compromised by pressure-reducing valves that were improperly set and provided insufficient pressure for 45mm hose using automatic fog nozzles. Firefighters attempted to overcome this problem by boosting the pressure in the standpipe system using pumpers. The valves, however, prevented the standpipe outlet pressure from increasing and unfortunately the fire crews did not have the expertise or tools to deal with the problem adequately.
They then proceeded to stretch a 100mm supply line up the stairwell to the 22nd floor. This, however, took more than one hour and at this stage the fire was spreading vertically by lapping from window to window.
In the meantime, the fire had burned through the main electrical feed thereby short circuiting the building’s entire power system. The primary and back-up electrical feeds were installed in a common, unprotected shaft. All lighting, elevators, pumps, fans and other electrical system were rendered inoperable because of this.
Three firefighters who were doing ventilation operations became disoriented and exhausted their air supply on the 28th floor. They died from asphyxiation before rescue teams could reach them.
By the time a sustained water supply was established, the volume of fire was too large to be controlled by handlines and after ten hours into the incident, all crews were withdrawn and it was decided to attack the fire with master streams from adjacent buildings. The fire, however, continued to extend vertically until it reached the 30th floor when it was controlled nine hours later by ten sprinklers installed on that floor.
The Meridian Plaza fire loss is estimated at US$2 billion, which makes it the costliest high rise building fire in American history.
On 3 March 1997, Pretoria Fire Department responds to a fire in their nine-storey civic centre (Munitoria) soon after close of business.
The first arriving engine crew encountered a fire in the lower ground floor roof void, which was already well developed and spreading rapidly.
Approximately five hours later, one entire wing of the L-shaped building is fully involved in the fire. The sides of the structure had mostly burned and a strong breeze was pushing the fire at a fair rate. A fire attack by crews on the sixth, seventh and eighth floors were successful in stopping the fire but the intensity of the fire column was such that crews on these floors were facing large rollovers, which prevented them from moving forward. A number of fire departments from surrounding cities and as far as Boksburg and Sandton were requested to assist. The placement of two aerial devices on the southern and eastern sides of the building allowed for the application of master streams into these floors, which, in my opinion, ultimately extinguished the fires.
Additional problems faced by crews was the gas cylinders that were located in the building’s kitchen/mess facility and ammunition, which belonged to the Pretoria Metro Police Department located on the 7th floor, which started cooking off and exploding thereby increasing the pucker factor of firefighters in the immediate vicinity exponentially.
I am of the opinion that the management of so many different fire services on this fire was well done and that the combined effort ultimately led to a successful operation. There was no loss of life, however, the monetary cost as well as the loss of many historic documents, was massive.
Multi-storey buildings exist in virtually every town and city in this country. They may vary in building age, size, height, construction, occupancy type and design features, including the fire safety design and fixed fire protection systems installed in them. Fire departments having to respond to fires in multi-storey buildings (and that is almost all of us) need to appreciate the added challenge that goes with these operations. Even the most practiced tasks such as ventilation, hose deployment and search and rescue will have an added dynamic, which will test the ability of responders to adapt and deal with the incident effectively.
In the event that the fire is located above the level of your aerial apparatus, it will be necessary to access the fire through the interior means. This will take much longer to achieve and critically delay your initial attack.
Depending on the occupancy type and time of day, you might encounter many building occupants who have been exposed to smoke and heat above the fire floor trying to exit through the same route as your firefighters are trying to enter, only in opposite directions. They might be cut off and be trapped on floors above the fire floor, meaning your evacuation will have to be through another route.
Ventilation will have its own challenges as vertical ventilation will be severely limited and generally not be an option. Horizontal ventilation might be your only option and this could again be restricted by the design of the building.
The effectiveness of the firefighting effort will be heavily reliant on the installation of fixed fire protection systems and the ability of the fire department to effectively use them to get sufficient water to the fire areas.
A lot of this will be dependent on good communication. In a high rise structure, this might be compromised by the buildings concrete and steel infrastructure.
A large multi-storey structural fire is a complex tactical environment and will require large forces of firefighters working together in a well-coordinated and structured way. Effective coordination of strategy and tactics are vital if we are going to succeed.
First due response
The first challenge to be encountered by the first in units will be to find sufficient open space to stage their vehicles. Most high rise buildings front towards a (normally busy) street with very little space created for large fire trucks. Your initial aerial apparatus placement must provide you the best vantage point for rescue and the later establishment of large master streams. You might have to ensure sufficient space to site two ladder trucks in the front of the building and at least one at the back, depending on the location of the fire.
Any high rise structural fire must be a multi-alarm fire from the get-go. You can’t afford a single engine response and although I have always advocated at least two engine companies and one ladder truck company as the initial response, it can’t be limited to so few units. The ‘two-plus-one’ first response should be the minimum first arrival but thereafter the multiple alarm units should be turning up in their numbers. Even with this turnout you will be hard pressed to make any impact on a well-developed working fire. The myriad of tasks required will quickly overwhelm the first-in units and it is vital that the incident commander does not attempt to do ‘everything’ this early on. If possible, try to extinguish the fire as soon as possible. Don’t allow yourself get distracted by obvious rescue problems or reports of people trapped upon arrival. “Don’t allow yourself to lose sight of your responsibilities and objectives. Engine companies make rescues by putting the fire out! Once that is accomplished, there are no more rescue problems!” Quote by Captain Dan Troxell, The District of Columbia Fire Department (DCFD), Engine 15.
A well-developed working fire is going to require a multi-alarm response. The first-in units (if it is not possible to extinguish the fire by themselves) should focus on the actions that will allow the later arriving forces to be effective. Their activities should include the following:
Lobby control sector
The second arriving company will be responsible for establishing the lobby sector. Their primary task will be to secure the lobby and coordinate all activities related thereto. Primary among these will be the control of incoming units and directing their movements to the determined positions.
The company assigned to the lobby sector should access the fire control room and alarm panel, which will assist them to confirm the location of the fire. They should establish entry points for later arriving entry teams and make sure that they are clearly indicated. All units entering the building should be passing through the lobby and it is here where an effective accountability system will be of great value.
The building’s elevators and heating, ventilation and air conditioning (HVAC) systems can also be controlled from here. It might be necessary for the building’s maintenance manager to assist in controlling an advanced HVAC system.
Should the lobby area allow it, you can establish an equipment staging area here. Take care though, that you do not block any access or egress routes or restrict the movement of fire crews and victims by doing this.
Staging areas
Primary staging
The primary staging area for crews should be two floors below the fire floor. This will be the position that crews assemble before being committed to the firefighting operation. The staging area will also be used for teas to exchange their self-contained breathing apparatus (SCBA) cylinders and as a rehab area for crews coming off the fire floor. A medical post can also be established here for the primary emergency care.
The interior operations sector commander will need to have an accurate picture of what is happening in the staging area so that he/she knows what resources can be committed to the fire attack and used for other support operations such as stretching hose lines, forcible entry and search.
Teams moving from their rigs to the staging area must take all the equipment they might need with them and ensure that it is placed in an equipment pool that is well lit and easily accessible. A check-in system for personnel and equipment should be initiated for the following two reasons:
Planning for high rise fires should include configuring your equipment so that it will be easier to carry them up multiple floors and easily deploy them when you get there. Carrying high rise packs on your rigs will allow you to do just this. There are a number of variations on this theme; ideally you would want to have it include sufficient hose to start and extend far enough for an initial attack (or extend far enough to continue your advance), the nozzle and some basic forcible entry tools. The hose should be so coiled as to easily deploy in a confined area such as a debris-laden passage or stairwell.
Finally, always make sure that all persons are able to hear the commands of the officers in charge of the various sectors to which they are deployed and that a good communications system is in place.
Secondary staging
This is where incoming units not directly involved in the initial fire attack will report. An officer should be deployed to command this sector.
This sector should be close enough for crews to move effortlessly to the incident scene but sufficiently far back as not to be in danger from any risks such as falling debris, traffic, etc.
An area should also be made available for the placement of equipment and refilling of SCBA cylinders. All equipment placed in the staging area should be noted and move into the primary staging area upon request.
The secondary staging area location must be given to all arriving units well in advance of their arrival on scene. These units must upon arrival report to the staging sector commander with information on their unit and its capabilities. It might be a good time to mention the vehicle typing system used internationally and also now being implemented in the Western Cape fire services. The Chief Fire Officers Committee in the province recently approved a system whereby all fire/rescue vehicles in various services are classified according to a pre-determined typing system. This allows the secondary staging officer to know exactly what the capability of the arriving resource is the moment it pulls up to the scene.
Secondary staging should be considered early on in the scene. A lot of fire trucks will be arriving and every firefighter on those trucks will want to ‘get-in-there’. As the responsible sector officer, you will need to be ready for some unhappiness and controversy. As incident commander you should try to make it clear to despatch what the specific resource is you will need. If you have enough vehicles, don’t ask for more unless you (a) need them and (b) know where you are going to place them. Remember, an incident commander calling for more units he/she doesn’t need could be the same as General Custer calling for more Indians.
Water supply
Most modern high rise buildings have fixed fire suppression systems and booster pumps to provide adequate pressure on all floors. You will, however, also encounter older buildings that do not have much fixed fire protection (other than dry standpipes).
As mentioned in the example of the Meridian building above, things could go wrong with these systems and it is important that the water supply sector is immediate established and starts supplementing the fixed systems as soon as possible. We are not always sure of how well the maintenance of these buildings is being done so it’s better to take that eventually out of the equation.
Incident command
If you can't make an educated guess as to how a building will perform under fire conditions, you are putting yourself and everybody else in danger.
Command of a high rise fires begins long before the actual response. Incident commanders must be skilled and experienced enough in all the aspects of high rise firefighting to confidently make the decisions needed to effectively deal with the fire. A fire in a multi-storey building will not only follow the laws of nature but also be dictated to by the fixed systems in the fire such as the HVAC system, occupation type, design, etc. Your command team must take all these factors into account when deciding on the plan of attack. Fire is always changing and you cannot be stationary in your attitude to something that is always changing. Move with the incident and make sure you build into your command procedures a system where you can do a progress check at regular intervals where you just follow up where you are in progressing towards your final objective. It takes cool heads to fight hot fires.
Up to now I have focussed mainly on an interior attack strategy for high rise fires. You may, however, be confronted by a major fire on arrival and have to make the decision to go defensive. The placement of master streams and possibility of structural collapse will become some of your prime objectives. Rescue of people also becomes a far greater risk and the use of aircraft resources becomes a necessity. Try to train with these resources as often as possible, although this is not an easy exercise. You don’t want to have to do this for the first time when the fire is pushing up towards the roof and you have people screaming for help on the roof.
“It is far easier to justify to a property owner why you went defensive than to explain to a grieving widow why you didn’t.” - Captain Joseph Knitter, training officer, South Milwaukee Fire Department, South Milwaukee, Wisconsin.
In closing
I have barely scratched the surface of the complexities related to high rise firefighting in this article. We still need to look at locating the fire, fire attack techniques, search and rescue, use of elevators, etc. I will attempt to do so in future editions. As a firefighter who responded to a few high rise fires in my career, I’m sure I know only enough to make me go out and learn more and this is what I urge all firefighters to do. The day you say ‘I know it all,’ please follow it with ‘I therefore submit my resignation.’”
High-rise firefighting
By Colin Deiner, Chief Director, Disaster Management and Fire Brigade Services, Western Cape Government
On 23 February 1991, a fire is started on the 22nd floor of the 38-floor Meridian Plaza building in Philadelphia, Pennsylvania. It was later found that the fire originated in a pile of oil-soaked rags. A smoke detector on the 22nd floor detected the fire but due to poor coverage of the system, the fire had already spread significantly at this time.
Firefighting operations were severely compromised by pressure-reducing valves that were improperly set and provided insufficient pressure for 45mm hose using automatic fog nozzles. Firefighters attempted to overcome this problem by boosting the pressure in the standpipe system using pumpers. The valves, however, prevented the standpipe outlet pressure from increasing and unfortunately the fire crews did not have the expertise or tools to deal with the problem adequately.
They then proceeded to stretch a 100mm supply line up the stairwell to the 22nd floor. This, however, took more than one hour and at this stage the fire was spreading vertically by lapping from window to window.
In the meantime, the fire had burned through the main electrical feed thereby short circuiting the building’s entire power system. The primary and back-up electrical feeds were installed in a common, unprotected shaft. All lighting, elevators, pumps, fans and other electrical system were rendered inoperable because of this.
Three firefighters who were doing ventilation operations became disoriented and exhausted their air supply on the 28th floor. They died from asphyxiation before rescue teams could reach them.
By the time a sustained water supply was established, the volume of fire was too large to be controlled by handlines and after ten hours into the incident, all crews were withdrawn and it was decided to attack the fire with master streams from adjacent buildings. The fire, however, continued to extend vertically until it reached the 30th floor when it was controlled nine hours later by ten sprinklers installed on that floor.
The Meridian Plaza fire loss is estimated at US$2 billion, which makes it the costliest high rise building fire in American history.
On 3 March 1997, Pretoria Fire Department responds to a fire in their nine-storey civic centre (Munitoria) soon after close of business.
The first arriving engine crew encountered a fire in the lower ground floor roof void, which was already well developed and spreading rapidly.
Approximately five hours later, one entire wing of the L-shaped building is fully involved in the fire. The sides of the structure had mostly burned and a strong breeze was pushing the fire at a fair rate. A fire attack by crews on the sixth, seventh and eighth floors were successful in stopping the fire but the intensity of the fire column was such that crews on these floors were facing large rollovers, which prevented them from moving forward. A number of fire departments from surrounding cities and as far as Boksburg and Sandton were requested to assist. The placement of two aerial devices on the southern and eastern sides of the building allowed for the application of master streams into these floors, which, in my opinion, ultimately extinguished the fires.
Additional problems faced by crews was the gas cylinders that were located in the building’s kitchen/mess facility and ammunition, which belonged to the Pretoria Metro Police Department located on the 7th floor, which started cooking off and exploding thereby increasing the pucker factor of firefighters in the immediate vicinity exponentially.
I am of the opinion that the management of so many different fire services on this fire was well done and that the combined effort ultimately led to a successful operation. There was no loss of life, however, the monetary cost as well as the loss of many historic documents, was massive.
Multi-storey buildings exist in virtually every town and city in this country. They may vary in building age, size, height, construction, occupancy type and design features, including the fire safety design and fixed fire protection systems installed in them. Fire departments having to respond to fires in multi-storey buildings (and that is almost all of us) need to appreciate the added challenge that goes with these operations. Even the most practiced tasks such as ventilation, hose deployment and search and rescue will have an added dynamic, which will test the ability of responders to adapt and deal with the incident effectively.
In the event that the fire is located above the level of your aerial apparatus, it will be necessary to access the fire through the interior means. This will take much longer to achieve and critically delay your initial attack.
Depending on the occupancy type and time of day, you might encounter many building occupants who have been exposed to smoke and heat above the fire floor trying to exit through the same route as your firefighters are trying to enter, only in opposite directions. They might be cut off and be trapped on floors above the fire floor, meaning your evacuation will have to be through another route.
Ventilation will have its own challenges as vertical ventilation will be severely limited and generally not be an option. Horizontal ventilation might be your only option and this could again be restricted by the design of the building.
The effectiveness of the firefighting effort will be heavily reliant on the installation of fixed fire protection systems and the ability of the fire department to effectively use them to get sufficient water to the fire areas.
A lot of this will be dependent on good communication. In a high rise structure, this might be compromised by the buildings concrete and steel infrastructure.
A large multi-storey structural fire is a complex tactical environment and will require large forces of firefighters working together in a well-coordinated and structured way. Effective coordination of strategy and tactics are vital if we are going to succeed.
First due response
The first challenge to be encountered by the first in units will be to find sufficient open space to stage their vehicles. Most high rise buildings front towards a (normally busy) street with very little space created for large fire trucks. Your initial aerial apparatus placement must provide you the best vantage point for rescue and the later establishment of large master streams. You might have to ensure sufficient space to site two ladder trucks in the front of the building and at least one at the back, depending on the location of the fire.
Any high rise structural fire must be a multi-alarm fire from the get-go. You can’t afford a single engine response and although I have always advocated at least two engine companies and one ladder truck company as the initial response, it can’t be limited to so few units. The ‘two-plus-one’ first response should be the minimum first arrival but thereafter the multiple alarm units should be turning up in their numbers. Even with this turnout you will be hard pressed to make any impact on a well-developed working fire. The myriad of tasks required will quickly overwhelm the first-in units and it is vital that the incident commander does not attempt to do ‘everything’ this early on. If possible, try to extinguish the fire as soon as possible. Don’t allow yourself get distracted by obvious rescue problems or reports of people trapped upon arrival. “Don’t allow yourself to lose sight of your responsibilities and objectives. Engine companies make rescues by putting the fire out! Once that is accomplished, there are no more rescue problems!” Quote by Captain Dan Troxell, The District of Columbia Fire Department (DCFD), Engine 15.
A well-developed working fire is going to require a multi-alarm response. The first-in units (if it is not possible to extinguish the fire by themselves) should focus on the actions that will allow the later arriving forces to be effective. Their activities should include the following:
- Size-up and initial assessment
- Building entry
- Initial equipment staging
- Determining the extent of the fire
- Determine the confirmed and possible location of entrapped occupants
- Movement of personnel and equipment to the reported location (fire floor)
- Initial report (including findings and initial actions taken)
- Commence fire attack
Lobby control sector
The second arriving company will be responsible for establishing the lobby sector. Their primary task will be to secure the lobby and coordinate all activities related thereto. Primary among these will be the control of incoming units and directing their movements to the determined positions.
The company assigned to the lobby sector should access the fire control room and alarm panel, which will assist them to confirm the location of the fire. They should establish entry points for later arriving entry teams and make sure that they are clearly indicated. All units entering the building should be passing through the lobby and it is here where an effective accountability system will be of great value.
The building’s elevators and heating, ventilation and air conditioning (HVAC) systems can also be controlled from here. It might be necessary for the building’s maintenance manager to assist in controlling an advanced HVAC system.
Should the lobby area allow it, you can establish an equipment staging area here. Take care though, that you do not block any access or egress routes or restrict the movement of fire crews and victims by doing this.
Staging areas
Primary staging
The primary staging area for crews should be two floors below the fire floor. This will be the position that crews assemble before being committed to the firefighting operation. The staging area will also be used for teas to exchange their self-contained breathing apparatus (SCBA) cylinders and as a rehab area for crews coming off the fire floor. A medical post can also be established here for the primary emergency care.
The interior operations sector commander will need to have an accurate picture of what is happening in the staging area so that he/she knows what resources can be committed to the fire attack and used for other support operations such as stretching hose lines, forcible entry and search.
Teams moving from their rigs to the staging area must take all the equipment they might need with them and ensure that it is placed in an equipment pool that is well lit and easily accessible. A check-in system for personnel and equipment should be initiated for the following two reasons:
- It will give the sector commanders an accurate picture of the resources available to them
- The people responsible for the staging sector will know what equipment will need to be brought up to them
Planning for high rise fires should include configuring your equipment so that it will be easier to carry them up multiple floors and easily deploy them when you get there. Carrying high rise packs on your rigs will allow you to do just this. There are a number of variations on this theme; ideally you would want to have it include sufficient hose to start and extend far enough for an initial attack (or extend far enough to continue your advance), the nozzle and some basic forcible entry tools. The hose should be so coiled as to easily deploy in a confined area such as a debris-laden passage or stairwell.
Finally, always make sure that all persons are able to hear the commands of the officers in charge of the various sectors to which they are deployed and that a good communications system is in place.
Secondary staging
This is where incoming units not directly involved in the initial fire attack will report. An officer should be deployed to command this sector.
This sector should be close enough for crews to move effortlessly to the incident scene but sufficiently far back as not to be in danger from any risks such as falling debris, traffic, etc.
An area should also be made available for the placement of equipment and refilling of SCBA cylinders. All equipment placed in the staging area should be noted and move into the primary staging area upon request.
The secondary staging area location must be given to all arriving units well in advance of their arrival on scene. These units must upon arrival report to the staging sector commander with information on their unit and its capabilities. It might be a good time to mention the vehicle typing system used internationally and also now being implemented in the Western Cape fire services. The Chief Fire Officers Committee in the province recently approved a system whereby all fire/rescue vehicles in various services are classified according to a pre-determined typing system. This allows the secondary staging officer to know exactly what the capability of the arriving resource is the moment it pulls up to the scene.
Secondary staging should be considered early on in the scene. A lot of fire trucks will be arriving and every firefighter on those trucks will want to ‘get-in-there’. As the responsible sector officer, you will need to be ready for some unhappiness and controversy. As incident commander you should try to make it clear to despatch what the specific resource is you will need. If you have enough vehicles, don’t ask for more unless you (a) need them and (b) know where you are going to place them. Remember, an incident commander calling for more units he/she doesn’t need could be the same as General Custer calling for more Indians.
Water supply
Most modern high rise buildings have fixed fire suppression systems and booster pumps to provide adequate pressure on all floors. You will, however, also encounter older buildings that do not have much fixed fire protection (other than dry standpipes).
As mentioned in the example of the Meridian building above, things could go wrong with these systems and it is important that the water supply sector is immediate established and starts supplementing the fixed systems as soon as possible. We are not always sure of how well the maintenance of these buildings is being done so it’s better to take that eventually out of the equation.
Incident command
If you can't make an educated guess as to how a building will perform under fire conditions, you are putting yourself and everybody else in danger.
Command of a high rise fires begins long before the actual response. Incident commanders must be skilled and experienced enough in all the aspects of high rise firefighting to confidently make the decisions needed to effectively deal with the fire. A fire in a multi-storey building will not only follow the laws of nature but also be dictated to by the fixed systems in the fire such as the HVAC system, occupation type, design, etc. Your command team must take all these factors into account when deciding on the plan of attack. Fire is always changing and you cannot be stationary in your attitude to something that is always changing. Move with the incident and make sure you build into your command procedures a system where you can do a progress check at regular intervals where you just follow up where you are in progressing towards your final objective. It takes cool heads to fight hot fires.
Up to now I have focussed mainly on an interior attack strategy for high rise fires. You may, however, be confronted by a major fire on arrival and have to make the decision to go defensive. The placement of master streams and possibility of structural collapse will become some of your prime objectives. Rescue of people also becomes a far greater risk and the use of aircraft resources becomes a necessity. Try to train with these resources as often as possible, although this is not an easy exercise. You don’t want to have to do this for the first time when the fire is pushing up towards the roof and you have people screaming for help on the roof.
“It is far easier to justify to a property owner why you went defensive than to explain to a grieving widow why you didn’t.” - Captain Joseph Knitter, training officer, South Milwaukee Fire Department, South Milwaukee, Wisconsin.
In closing
I have barely scratched the surface of the complexities related to high rise firefighting in this article. We still need to look at locating the fire, fire attack techniques, search and rescue, use of elevators, etc. I will attempt to do so in future editions. As a firefighter who responded to a few high rise fires in my career, I’m sure I know only enough to make me go out and learn more and this is what I urge all firefighters to do. The day you say ‘I know it all,’ please follow it with ‘I therefore submit my resignation.’”