Q: Could help me clarify a code issue I'm running into? It's sort of a two-part question.
1. The elevator lobby with stair doors located inside the tenants space and the entry doors are secured by card access. The right thing seems to be to recommend fail-safe locks on the doors and fire system relays. It would seem that these doors should be considered under the same guidelines as stair doors, which would require failsafe locks but be positively latched. What would be your recommendation and do you know of any code that addresses this exact scenario?
2. What is the definition of fire rated door? It can't just simply be any door with an exit sign posted in front of it. Don't many lobby level main entrances have exit signs and they do not have to be positively latched, right?
It surprises me that there are no clear guidelines for these situations.
Egress doors must provide fail-safe operation.
A: Resolving the code issues you pose is valuable. It enables installing dealers to protect the public and deepens understanding of codes and safe practices.
Your comment about there being no clear guidelines in the codes is a bit unfounded. There are so many variations in architectural design; so many new security systems; and an ever increasing awareness of the potential life safety issues, that it is no longer surprising to encounter a situation that is not specifically addressed in the code. But still, the code writing groups are doing a pretty good job. Experience, and a knowledge of the existing codes helps you to Think Like An AHJ. Also realize that the codes are under constant review.
Codes differ from area to area but here are some universal standards for fire-rated doors. The wall, frame, and door all have to be fire rated. It would not make much sense to put a labeled door in a non rated wall just as you can't put a non labeled door in a rated wall and call the opening fire rated. The purpose of a fire rated opening is to retard fire for a specific period of time. All components of the opening will have to be rated.
The door must be self-closing. If the door is left open during a fire, that opening can't retard the fire as it was meant to so the door has to close after somebody passes through it. This is usually done by a door closer or spring hinges. Both serve the same purpose in that the door will close and serve it's purpose of holding back the fire.
The door must be self-latching. Push and pull plates cannot be used on a fire rated door. The door has to latch into the frame when closed so it stays shut until it is manually opened. This prevents the door from opening during a fire if something falls against it.
Steel ball bearing hinges must be used. Brass, bronze and other bases cannot be used, and hinges must have a steel base on fire rated doors. Plain bearing hinges cannot be used either. Ball bearing hinges ensure the door will not come loose from the frame and fall out of the opening.
The purpose of a fire rated opening is to retard fire for a specific period of time. Most labeled doors will have an A, B, or C label.
A label: 3 hour rating (for a 4 hour wall). These doors are used for openings in walls separating buildings that are joined together. No glass is allowed in these doors.
B label: 1 1/2 hour rating (for a 2 hour wall). These doors are usually used for stairwell doors but are sometimes used at all the rated walls in a building. 100 square inches of exposed glass is allowed.
C label: 3/4 hour rating (for a 1 hour wall). These doors are used for openings from a corridor into another room in the same building. 1296 square inches of exposed glass is allowed.
The arrangement of having to gain access to exit stairs that are located outside of an elevator lobby is a somewhat undesirable practice. NFPA 101: 220.127.116.11 specially addresses the situation by not allowing that particular arrangement in the current code.
The 2003 edition of the Code states: 18.104.22.168 Elevator lobbies shall have access to at least one exit. Such exit access shall not require the use of a key, a tool, special knowledge, or special effort.?
Robert Solomon, PE National Fire Protection Association advises: The NFPA Technical Committee on Means of Egress is currently evaluating this issue further. A proposal that has been accepted at this stage of the NFPA code development process is adding in specific language to allow for the specific lobby configuration described. A number of fail safe measures are included that will require the doors to unlock if:
Power is lost.
A manual release device is
The fire alarm system is activated.
The automatic sprinkler system is activated.
All doors leading from the elevator lobby to stairwell exits are considered door in the means of egress (NFPA 80). This could be the entrance door to an office suite and possibly a traffic control door beyond the main entrance. They may not restrict egress in the event of a fire.
Your guess that they need to provide fail-safe operation is correct. The power supply must also be tied into the fire alarm system so as to drop power (not electrically release the trim or lock) in the event of an emergency.
Indifference Defeats the Best Engineering
Q: If you spend any amount of time out in the field, you come to realize how poor training can overcome the best engineering and planning. Recently, while surveying a premise, I happened to notice the wireless alarm transmitters on several doors of the premises didn't seem quite right.? Upon closer examination, I discovered that indeed the transmitter bases had been attached to the door or the frame upside down using two-sided tape. This can't be acceptable, can it?