1.1 Purpose: The purpose of this document is to assist the building official and those regulated by 780 CMR in judging the acceptability of compliance alternatives to specific provisions required by 780 CMR.
1.2 Application: This document contains generally acceptable compliance alternatives and examples. The examples are solely for the purpose of illustrating principles which can be applied to the solution of code compliance problems and are not necessarily acceptable under all circumstances. It is recognized that all building systems interact with each other. Therefore, any consideration of compliance alternatives must take into account all existing and proposed conditions to determine their acceptability. The principles applied can be used for the solution of similar compliance problems in other buildings and occupancy groups. Commentaries are provided where the philosophy in establishing the alternatives is not obvious. The examples were developed from appeal data and accepted practice. They are not all-inclusive and should not preclude consideration of other alternatives.
Note: It is anticipated that additional compliance alternatives will be added to Appendix 1.0 through the mechanism of appeal decisions and from results of research being conducted by various organizations in the field of relative permanence of life safety systems.
2. Provide alternate egress facilities (windows, etc.).
3. Provide a fire escape.
4. Provide fire-rated areas of refuge.
Example 1 involves a five-story Building of Use Group B without a fire suppression system and with only one means of egress.
Solution A. Add one or more fire escapes as may be necessary to provide all tenants with reasonable access to two means of egress in separate directions. Access to a street, public way or area of refuge shall be provided at the termination of the fire escape.
Solution B. Add connecting fire balconies across fire walls if the above solution is impractical due to construction difficulties.
Example 2 involves a building of Use Group R-2 occupancy with an apartment in the basement. There is only one means of egress from the basement.
Solution A. Provide egress windows in each apartment that comply with 780 CMR 10.
2.2 Travel Distance:
2.2.1 General Compliance Alternatives:
1. Add detection system.
2. Add a partial fire suppression system.
3. Add smoke doors.
4. Increase fireresistance rating of corridor walls and doors.
2.2.2 Example: This example involves a four story building of Use Group R-2 without a fire suppression system. The length of exitway access travel is 150 feet.
Solution A. Add a partial fire suppression system off the domestic water supply (if adequate) in the exit access corridor.
Solution B. Subdivide corridor into segments, if less than 100 feet, with smoke doors.
Solution C. If not required by other sections of 780 CMR, install smoke and fire detectors with audible alarms in the corridor.
Solution D. Increase the fireresistance rating of the exit access corridor from one hour to two hours and provide "B" label self-closing or automatic closing fire doors in all openings into the corridor.
2.3 Enclosure of exitways:
2.3.1 General Compliance alternatives:
1. Improve enclosure of exitway.
2. Add a partial fire suppression system.
3. Add a detection system.
2.3.2 Examples: This example involves a four story row building of Use Group R-2 with connecting fire balconies and an interior stair. The stair is enclosed with lath and plaster, wood stud partitions and paneled doors.
Solution A. Cover partitions on the apartment side with 5/8" Type X gypsum wallboard or its equivalent. Replace or build up panel doors until minimum solid portion is 1" and install self-closers.
Solution B. Provide a heat and smoke detection system in the stairwell with an alarm audible to all tenants. Provide self-closers on all stairwell doors.
Solution C. Provide a partial fire suppression system in the stairwell off the domestic water supply (if adequate). Provide self-closers on all stairwell doors.
2.3.3 Commentary: The above example, while pertaining to a four story, Use Group R-2 building, can also be applied to other buildings of occupancies and floor levels. The principle that the degree of code compliance may not be reduced should be remembered. If the existing enclosure is of fireresistive construction, it must be maintained. The primary principle to remember, in the required enclosure of exitway, is that an enclosure must be provided, whether fireresistive or not, so as to provide a smoke barrier. The purpose of providing a smoke barrier is to prevent the passage of smoke from a fire on one floor to the exitways and exit access corridors of other floors and thus render them unusable for egress. This principle is illustrated by solutions A, B, and C in the above example.
3.0 COMPLIANCE ALTERNATIVES FOR FIRE HAZARDS
3.1 Fire separations and partitions;
3.1.1 General compliance alternatives:
1. Improve fire separation.
2. Add a fire suppression system.
3. Add a detection system.
Example 1 involves a three story building of Type 3A construction, containing a Mercantile (M) Use Group, on the first floor and occupancy Business (B) Use on the second and third floors. The required separation is two hours.
Solution A. Add a fire suppression system to the first and second floors.
Solution B. Add 2 x 5/8 inch Type X gypsum wallboard or its equivalent to the underside of the second floor and install a system of smoke and heat detectors with audible alarms on the first and second floors.
Example 2 involves the separation between two tenants of wood lath and plaster on a wood studs partition. The required separation is one hour.
Solution A. Add 5/8 inch Type X gypsum wallboard or its equivalent to either side of the existing partition.
Example 3 involves a building of Use Group B with unrated exit access corridors.
Solution A. Install a partial fire suppression system in the exit access corridors.
Solution B. Add 5/8 inch Type X gypsum wallboard or its equivalent to either side of the corridor partition and install self-closers on all corridor doors.
Solution C. Install a smoke and heat detection system in the corridor with and alarm audible to all tenants on the floor and install self-closers on all corridor doors.
3.2 Openings and exterior wall protection:
3.2.1 General compliance alternatives:
1. Add fire suppression system.
2. Improve fireresistance.
3. Remove or improve openings.
Example 1 involves a two story of Type 5B construction building, with Use Group M, on the first floor the basement and upper floors. The distance between the building and the side lot line is five feet and ten feet between it and the adjacent building. The adjacent building is of Type 5B construction and Use Group R-2. The former occupant was a grocery store; the new occupant is a hardware store. The required separation is one hour.
Solution A. Install a deluge sprinkler system along the interior side of the wall affected.
Solution B. Add 1 x 5/8 inch Type X gypsum wallboard to interior side of the wall affected.
Example 2 is the same as example 1 but with double-hung wood windows in affected wall.
Solution A. Remove windows and close opening with one hour fireresistive construction.
Solution B. Remove windows and install fire windows.
Solution C. Install a deluge sprinkler system as in solution A to example 1.