Multiuse High Rise Buildings

There are two questions that you have to answer it. initial posts should be between 150-500 words. ( I attached the document and there are different discussions from other students, and you have to Respond to at least three peer comments.)

Question 1: Multiuse High Rise Buildings

Multi-use highrise buildings are appearing with increasing frequency and pose interesting decisions for design professionals and regulatory authorities. Assume you are responsible for reviewing the design for such a large building. How would you approach the problem of setting requirements when there are multiple types of occupancies in the same building? The problem is not as simple as requiring fire-rated partitions between the different types of occupancies within the same building. Many of the issues concern human and organizational factors. Especially important is how the occupancies interact regarding exiting requirements. What if a building has an assembly occupancy on it’s second floor. Would you permit the theater patrons to leave using the main building entrance? If you required that most of the patrons leave using exits dedicated to the theater, how would you assure that they would use those exits instead of the main entrance?

Students Answer/

Student 1:

To start, the building will need to be designed with a Fire Alarm  System, and program to provide a phased evacuation (Notify floor of origin, the floor above, the floor below); the notification system will need to be voice communication with general selective paging for each floor. Secondly, the fire sprinkler system will need to be designed per the particular occupancy for each floor, with automatic standpipes (Class 1) in the stairwells and an automatic sprinkler on the landings in the stairwell. Third, transitional refuge areas (fire-rated pressurized spaces at various locations in particular for occupancies). Fifth, stairwell pressurization systems. Sixth, the stairwell egress must be wide enough between 66 -72 inches and strong enough to support phased evacuation.

With answering the questions

Yes, I would permit the patrons to leave through the main building entrance, I feel that many people in the theater will begin to backtrack how they entered the building, and we need to make sure we house the egress available for them to do so. However, I would provide alternate route and illuminate those routes when the fire alarm system does alarm as well making sure the staff responds to the alarm and assist with the evacuation.

Student 2:

In a multi occupanci building I think that I need to aprroch the situation in different way for every bilding.I think that more than use the main factor is how much peopl I need to evacuate. If I have a theater, I wuold create special doors for the evacuation just for them. The rapidly increse of people if they are going out for the general evacuation route, willl decrease the walking speed. If they go out out for that special doors, I will mantain the waliking speed in every part of the building. To asure that they will use those door, befero the show start I will put somethin that anounce whete are the emergency exits, I will put them in the side of the stage. 

Student 3:

The use of mutli use buildings requires looking at the different occupant loads and hazards of each type of use. There needs to be an examination of how different occupants of each facility are expected to act. There are expected to be occupants in the assembly occupancy  which need to be accounted for as oppose to possibly a supply facility with few occupants. For the assembly I would permit patrons to use the main entrance as that may be the safest at the time and its inevitable that some will retrace the route they entered. Each theater will have available exit points from within the theater that should be attempted to be used and I will ensure that they are properly identified and locations announced prior to each presentation. 

Student 4:

Performing plan reviews for a large building such as a high rise with multiple uses inside, one must start at the site where this large building will be constructed. Before this construction goes vertical, a lot of requirements must be met on the ground with adequate roadways, access roads, water mains and hydrants. Performance based design options are now used per floor of this high-rise to meet the current codes for egress requirements, number of exits, corridor widths, allowable fire areas through fire-rated partitions, smoke partitions in egress stairwells, fire-rated doors with magnets to close in an emergency to prevent smoke from spreading throughout, emergency lighting and exit signage elements, portable fire extinguishers all of which are code based upon the intended uses on each floor. Let’s not forget the fire sprinkler system required and the addressable fire alarm system too. These are requirements based upon fire codes and NFPA. Depending on the water flow and pressure into the building, a fire pump or pumps will more than likely be required to provide adequate pressure and volume to the upper floors of this high rise. Standpipe systems will also be required in the stairwells for firefighting operations out and to remote areas of the individual floors. If the building has an assembly area on the second floor, then with the designed use of active fire protection for life safety (fire sprinkler system), then allowances are given for corridor lengths are given, but HVAC systems and building ventilation design is required to be tied into the fire alarm which will trigger the building’s ventilation to remove smoke and exchange air to the outside of this high-rise. So, a discussion will ensure with the architect and engineers to determine if the current design warrants the additional capital of additional exits from the second floor or if current exits and egress paths are adequate with the fire protection systems to satisfy the architect’s performance-based design while meeting the code requirements for this design. 

Student 5:

The risks associated with residential high rise buildings (buildings over 6 stories) are countless to say the least. Most of these building have very effective fire suppression systems and detection beyond the floor involved. Adding a assembly on the second floor will not only increase the occupant load but require an effective plan for evacuation for all floors above due to convergence with escape routes. This starts the conversation of a phased evacuation where the main fire floor is evacuated and notified first. The stairwells in a mixed use occupancy, will need to be protected with a pressurized stairwell and fire sprinkler suppression systems and wide enough that the convergence of individuals can make egress accessible. In the case of a movie theatre, patrons will be willing to use the entrance as an exit but for this reason an alternate path should be used and staff should coordinate the evacuation plan with well-lit exit signs. A voice notification system should be used to alert all occupants of what floor will be involved.

Student 6:

  1. When a building is of mixed occupancy or used for more than one occupancy, the whole building shall be subject to the most restrictive requirement pertaining to any of the 
    type of occupancy found therein except in the 
    following:
  2.  When a one-story building houses more than one occupancy, each portion of the building shall conform to the requirement of the particular occupancy housed therein and;
    (2) Where minor accessory uses do not occupy more than ten percent of the area of any floor or a building, nor more than ten percent of the basic area permitted in the occupancy requirements, in which case, the major use of the building shall determine the occupancy classification.

Forms Of Occupancy Separation

  1. Occupancy separations shall be vertical or horizontal or both, or when necessary, of such other forms as may be required to afford a complete separation between the various occupancy divisions in the building.

Types of Occupancy Separation

  1. Occupancy separation shall be classified as “One-Hour Fire-Resistive”, “Two-Hour Fire-Resistive”, “Three-Hour Fire-Resistive” and “Four-Hour Fire-Resistive.”
  2. A “One-Hour Fire-Resistive Occupancy Separation” shall be of not less than one-hour fire-resistive construction.  All openings in such separation shall be protected by a fire assembly having a one-hour fire-resistive rating
  3.  A “Two-Hour Fire-Resistive Occupancy Separation” shall be of not less than two-hour fire-resistive construction.  All openings in such separation shall be protected by a fire assembly having a two-hour fire-resistive rating.
  4. A “Three-Hour Fire-Resistive Occupancy Separation” shall be of not less than three-hour fire-resistive construction.  All openings in walls forming such separation shall be protected by a fire assembly having 
    a three-hour fire-resistive rating.
  5. The total width of all openings in any three-hour fire-resistive occupancy separation wall in any 
    one-story shall not exceed 25 percent of the length of the wall in that story and no single 
    opening shall have an area greater than 10square meters.  All openings in floors forming a “Three-Hour Fire Resistive 
    Occupancy Separation” shall be protected by vertical enclosures extending above and 
    below such openings. 
  6. The walls of such vertical enclosures shall be of not less than two-hour fire-resistive construction, and all 
    openings therein shall be protected by a fire assembly having a three-hour fire-resistive 
    rating.
  7. A “Four-Hour Fire-Resistive Occupancy 
    Separation” shall have no openings therein and shall be of not less than four-hour fire-
    resistive construction.
     

Fire Rating for Occupancy Separation

  1. Occupancy Separations shall be provided between groups, subgroupings, or divisions of occupancies.  The Secretary shall promulgate rules and regulations for appropriate occupancy separations in buildings of mixed occupancy; Provided, that, where any occupancy separation is required, the minimum shall be a “One-Hour Fire-Resistive Occupancy Separation”; and where the occupancy separation is horizontal, structural members supporting the separation shall be protected by an equivalent fire-resistive construction.

Question 2: Bias Towards Familiar Egress Routes and Implications for the Fire Alarms

This second question builds off of Question 1this week. Keep in mind that people show a strong bias toward using familiar egress routes. What are the implications for a fire alarm system? Would you want the fire alarm system to operate differently for different parts of the building? If there was a day care facility within this building that helped serve those individuals that worked in the building, what problems would you expect?  Would you expect parents to try to reach the day care center before evacuating the building? What recommendation would you make to encourage parents not to travel to the day care center?

Students Answer/

Student 1:

Yes, I would want the fire alarm to operate differently for a high-rise building by providing a phased evacuation (Notify floor of origin, the floor above, the floor below)

If there is a daycare in the building, there are many issues. One example, there is usually one teacher to about eight toddlers, so trying to get eight toddlers downstairs by yourself with other adults trying to go down the stairs will be a failure. Another example is the issues with the handrails and steps that are in a stairwell.

Yes, I would expect parents to try to reach the daycare before evacuating a building. As a parent, it will be difficult to stop me or, better yet, my wife from getting my kids if we know there is a fire in a high-rise building. The recommendation is to make sure each parent knows the evacuation process for the daycare, and if they impede it will slow the evacuation down.

I want to add additional content about the daycare in a high-rise building. I think it is essential when or if the design is created for the building; the daycare should be placed closest to the ground level. Also, it would be ideal for the daycare to have its own elevator or stairwell to exit. If that is not possible, at minimum, the area or zone will need to be fully sprinklered and to be designed as a transitional refuge area. Finally, the daycare staff needs to be notified soon as an event happens so that staff can start their fire evacuation plan.

Student 2:

This is one difficult situation to work, the people noramally wait to go out, think what it go to happend if they have a kid inside the building. The implication fortheis alamr,are that need to be something really loud and anoying, something that make the people want to go out. Also, add coice direction dirrecting to the emergency doors. In the day care, I think that it need to be a bit quiet, I willl want to just let know to the teachers or the adults in the day care, I wil prefer have the kids in oreder, instead take a couple of more seconds. The systems need to operate different because every profile from the biulding will reacyt diffeent to the alarm.In the day care I would expect the teacher getting out with all the children,and the hall crwod try to pass. To solve this I would have a special route for the kids. Yes, I wuold expect the parents at some point reach for the kids, this can be a problem if the need to go in opposite directions in relation of the crowd. I will recomend give to the parents the hall plan of during a evacuation, detail per detail. WIth this I looking to let them know where the go to be after the evacuation. 

Student 3:

With people attempting to use familiar egress routes this would affect the alarm system by using phased evacuation by attempting to egress the ones in most severe danger to prevent a bottle neck of occupants. For the day care system I would ensure that all workers are fully aware of the evacuation procedures as well as a designated safe rally point for all children. I would also make sure that all parents that utilize the day care are clearly made aware of the dayscares evacuation procedures as well as the rally point where they can locate children instead of attempting to make access to children through the building. 

Student 4:

People are in fact creatures of comfort and like water will follow the path of least resistance. On a floor in a building with multiple uses such as a large assembly and a daycare, the fire alarm system would in fact notify everyone. In an assembly, large crowds of people will naturally assimilate and head to the same entrance / exit in which they arrived at the space. Best case, they may head to the closest exit by following the person in the front of them. In a daycare on the same floor, some children depending on their age may get excited or become frantic from the sound of the fire alarm system. They will be swept up by the teachers or aides in the classroom and then all will exit the building according to and as they were instructed. Once outside, an accountability system will take effect and the teachers and aides will account for all the children before notifies are made to parents if the event kept all occupants out of the building for an extended period of time.  

Student 5:

First off, people that are not familiar with buildings will tend to use the same way they came in . That being said when a fire alarm goes off, people will converge to the entrance with the highest density. Using voice communication systems in the parts of the building can help with evacuation when children are involved in a daycare facility. Parents will inherently want to ensure their children’s safety in the event of a fire. For this reason parents will try to make access to their children but a well-planned evacuation system where the parents can meet in a safe haven should be used. This gives a chance for the daycare facility to operate with known plans and accountability, plus reduce that panic of parents showing up and grabbing kids without anyone noticing. Parents and daycare officials can meet in a safe haven area and start a process for an orderly pick up. These evacuation procedures like I say in all of my posts “ should be trained on and reevaluated”. Fire drills are not just for kids.

Student 6:

In terms of the day care center, i would try and make room for it to be on the first floor so that it is easier for the employees of the day care to evacuate the children. In terms of making sure that the parents dont go to the day care before exiting i belive that there should be two seperate entrances so that you have to go outside to get to the day care’s entrance. This would make sure that people exit first and that the day care employees can focus on getting the kids out instead of worrying about the parents coming back in and possibly getting in the way. 

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