PROPOSED STANDARD SCHEDULE FOR GRADING CITIES AND TOWNS OF THE UNITED STATES WITH REFERENCE TO THEIR FIRE DEFENSES AND PHYSICAL CONDITIONS
Copyright, 1915, by the National Board of Fire Undewriters, New York.
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23. Minor Equipment.—Complete minor equipment shall be provided for each company; this to include shutoff nozzles from 3/4inch to l 1/4-inch and open smooth-bore nozzles from l 1/8-inch to l 1/2-inch, short ladders, portable extinguishers, salvage appliances, including waterproof covers, and sufficient small equipment to enable the firemen to perform their work with the greatest facility and despatch. Use 1/5 Deficiency Scale.
24. Fuel.—Good quality quick steaming coal, and gasoline where automobiles are used, shall be provided in sufficient quantities at convenient points and ready for quick handling. a. Poor engine fuel, 5 points, b. Inadequate methods of handling, 5 points.
25. Repair Facilities.—Adequate, preferably departmental, facliities for making repairs must be provided and sufficient spare apparatus and spare parts must be provided to prevent companies being out of service; approximately 1 hose wagon in 12 (1 in 8 for automobiles) and 1 ladder truck in 5 should be in reserve; exercise and supply wagons, if in good condition, may offset in part deficiency in hose wagons. It is particularly desirable to have equipment standardized; wheels, poles, all hose couplings, playpipes, tips, and minor equipment, Sparc poles, wheels and tires should be on hand. Repair facilities and spare apparatus and parts; Use 1/5 Deficiency Scale.
26. Horses.—Suitable horses shall be provided for all apparatus (except automobile) in service; reserve horses shall be provided, equal to 5 per cent, of the number in service, but not less than 2 horses where over 6 pieces of apparatus are in service, nor less than 1 horse where over 3 pieces of apparatus are in service. If hired horses are used or if horses are used for other than fire department purposes (street sprinkling, etc.), grade horses affected as 50 per cent, deficient. Use Deficiency Scale.
27. Fire Stations.—Houses shall be adapted for the service, as applying to ease and quickness of response; each engine or hose company station shall have hose-drying facilities. Houses unadapted for the service: Use 1/5 Deficiency Scale.
28. Regulations and Discipline.—Provision shall be made in complete printed regulations for control of the department and _ authority given the chief to enforce them, subject to review or confirmation by the supervising body or the civil service commission. Discipline shall be rigidly maintained and fines and suspensions impartially imposed and sustained. Provision for and enforcement of discipline: Use ⅛ Deficiency Scale.
39. Drills and Training.—Drills in charge of a competent officer shall be regularly held at a drill tower for all company members of the department. Drills shall be classed as not better than 30 per cent, deficient if only for newly enlisted men, or if no drill tower is provided. Use 1/5 Deficiency Scale.
30.Response to Alarms.—An adequate running card shall be established, providing for first and subsequent alarms, and for outlying companies to occupy vacated stations. Apparatus shall respond to all first (including telephone) alarms in amount commensurate with the normal hazard of the district, but not less than as follows: In mercantile and manufacturing districts: Not less than 2 engine or hose companies and 1 ladder company in cities under 25,000 and over 4,000 population. Not less than 3 engine or hose companies and 1 ladder company in cities over 25,000 and under 50,000. Not less than 4 engine or hose companies and 2 ladder companies in cities over 50,000. In residential districts: Not less than 2 engine or hose companies, except for cities under 4,000 population. For response to first alarms: a. Use ¾ Deficiency Scale for high value districts, b. Add ⅝ Deficiency Scale for residential. Note.—Deficiency to be figured separately for box alarms and telephone alarms, and the points of deficiency applied in ratio of the number of each kind to total first alarms. When the number of companies in service is in excess of the required first alarm response and the running card does not provide for response to second and subsequent alarms, nor for moving in of companies, add: c. No provision for subsequent alarms, 10 points, d. No provision for moving in, 10 points.
31. Fire Methods.—These shall be modern and include the liberal use of chemicals, shutoff nozzles and salvage appliances to reduce water damage, the use of appliances for powerful streams on serious fires, suitable ladder work and ventilation and the general policy of attaching lines to Siamese connections serving sprinklers and standpipes. Use ⅝ Deficiency Scale.
32. Engine Heaters.—Engines shall be on heaters in cities where they are depended upon for first streams. Engines not on heaters (when used for first streams), 10 points.
33. Building Inspections.—Systematic and frequent inspections shall be made by company and department officers to acquaint them with local conditions and records of such inspections shall be kept both by notes and sketches, a. Fair, 5 points, b. Poor, 10 points, c. Very poor, 20 points.
34. Records.—Proper records of all fires, fire methods, losses, apparatus and all department matters shall be kept. a. Fair, 5 points, b. Poor, 10 points, c. Very poor, 15 points.
FIRE ALARM SYSTEM.
Note.—Items 1 to 20, inclusive, to apply to a municipally owned or controlled telegraph system for receiving and transmitting alarms of fire. Items 21 to 26 are to apply to the auxiliary service furnished by telephone. Where no fire alarm telegraph system is installed, a total deficiency of 400 points shall be applied and additional points debited for deficiencies in such telephone service as is available, under Items 3 and 4 and Items 21 to 26, inclusive; credit to be given under Item 18, for street telephones accessible to the public, to the extent of ¼ the credit for municipally owned fire alarm boxes.
- Qualifications of Management.—Management to be competent and experienced, a. Management incompetent or inexperienced, 10 points, b. Management incompetent or inexperienced, very, 20 points.
- Maintenance Force.—Force to be adequate for maintenance or good provision for obtaining emergency help, and to be competent. Maintenance force inadequate or incompetent: Use 1/10 Deficiency Scale.
- Operators.—Operating force shall consist of some competent person, controlled by the municipality, but not necessarily at fire alarm headquarters, on duty at all times to handle telephone alarms; provided that in municipalities of less than 10,000 population ½ credit, and in larger cities ⅝ credit, may he given for a telephone operator on duty at the public exchange at all times, with facilities for transmitting alarms giving the definite location of the fire. In cities handling an average of over one alarm a day a fire alarm operator shall be on duty at fire alarm headquarters, and when manual operation is depended upon for transmission of alarms, two operators shall be on duty at all times. An operator of the telephone system, if capable of operating the fire alarm system, may be considered as one fire alarm operator. Operating force inadequate or incompetent: Use 1/5 Deficiency Scale.
- Headquarters.—Headquarters apparatus to be housed securely against fire, including danger from conflagration. When service is dependent upon the telephone exchange, application shall be made to the exchange building. Combustible material to be a minimum in mountings, etc. a. Headquarters nonfireproof, 15 points, b. Headquarters exposed and not protected, 15 points. c. Internal hazards severe, 10 points, d. No private fire protection in apparatus rooms, 5 points.
- Apparatus at Headquarters.—To be such as to ensure receipt, recording and transmission of all alarms and to be in good condition. Cities having over 100,000 population or more than 350 alarms a year shall have provision permitting transmission manually; if automatic transmission is also provided, means must be provided for cutting out the automatic feature. Telephone service not to be considered under this Item; see Items 21 to 26. a. For incomplete apparatus at headquarters: Use ¾ Deficiency Scale, b. For poor condition add 1/10 Deficiency Scale.
- Circuit Protection.—To consist of: Heavy current and sneak current fuse protection and lightning arresters at headquarters, so located as to prevent injury to any operating mechanism; lightning arresters and heavy current fuses at junction of underground and overhead construction, if any, and heavy current fuses on battery rack. Circuit Protection: a. Fair, 5 points, b. Poor, 10 points, c. Very poor, 20 points.
- Batteries.—Storage batteries in duplicate or generator sets with sufficient reserve, properly mounted in a well-heated and ventilated room, separate from other apparatus; in single-circuit systems, primary batteries may be used. Provision shall be made for obtaining a duplicate source of supply within 5 hours. Charging shall be normally from current of not over 250 volts, a. Poor type or mounting, 10 points. b. Insufficient, 10 points, c. Not well maintained, 5 points, d. No provision for duplicate source of current, 5 points, e. Charging normally from grounded circuit, 5 points.
- Circuits.—All circuits shall be underground; box circuits serving fire stations count as alarm circuits and shall be applied under both a and b below, a. Use 1/10 Deficiency Scale for box circuits, b. Add 1/10 Deficiency Scale for alarm circuits.
- Condition and Material of Circuits.— Circuits in underground and aerial cables shall be at least No. 14 gauge copper wire with rubber insulation in lead sheathing. All aerial circuits shall have conductivity of No. 10 galvanized iron wire and tensile strength of No. copper wire, with doubleor triple-braided weatherproof insulation. Poles to be substantial and wires, including box leads, to be well strung and free from injury. Use 1/5 Deficiency Scale. With good underground construction in high value districts, use 1/10 Deficiency Scale for condition of overhead elsewhere.
- 10. Circuits Near High Potential.—-Circuits shall not be in same duct or manhole nor on same pole with high potential circuits. Circuits on poles or in manholes with high potential circuits, a. Few, 5 points, b. Many, 10 points.
- Open or Grounded Circuits.—All box and alarm circuits and local headquarters’ circuits on which receipt, registering or transmission of alarm depends must be normally closed and under constant test. Normally open circuits: a. For each 10 per cent, of fire stations which may be affected, 2 points, b. And add for each 10 per cent, of boxes which mav be affected, 2 points. Ground return: c. For each 10 per cent, of stations affected. 1 point, d. Add for each 10 per cent, of boxes affected, 1 point.
- Circuits Overloaded.—There shall not be more than 20 boxes and/or instruments connected to any box circuit. Box circuits shall have only boxes, except in an automatic system registering instruments may be connected, each instrument counting as a box. No alarm circuit to connect instruments in more than 5 fire stations, a. Use 1/10 Deficiency Scale for box circuits, b. And add 1/20 Deficiency Scale for alarm circuits. Note: Do not apply in single circuit systems, where deficiency has been applied under Item 5, for lack of a repeater. In automatic system, if no alarm circuits are provided, do not apply under b unless more than 5 stations are on any one box circuit.
- Circuits to and Apparatus in Fire Stations.—Except where only a single circuit system is required, each fire station must receive alarms over two alarm circuits; in an automatic system, each box circuit must extend to some fire station and may count as one of the alarm circuits. Station apparatus must include a gong, a tapper and a permanent registering device, the register to be on the box circuit in an automatic system. Telephone apparatus not to be considered under this Item. a. For deficient circuits to fire stations: Use 1/10 Deficiency Scale, b. And add for deficient apparatus: 1/10 Deficiency Scale.
- Inside Wiring.—Wiring at Headquarters and in stations shall be in accordance with the National Electrical Code; wooden moulding not permitted. Circuits to enter stations in conduit, a. Use 1/10 Deficiency Scale for Headquarters, b. And add 1/20 Deficiency Scale for station wiring.
- Boxes.—Boxes, including private boxes, shall be non-interfering, and when more than 20 boxes are on the system shall be of successive type. a. Use 1/10 Deficiency Scale for interfering boxes or boxes of poor design, b.Add 1/20 Deficiency Scale for non-succession boxes.
- Conspicuousness and Accessibility of Boxes.—Public boxes and private boxes accessible to the public shall be conspicuous as applying to location and designation, and including red lights at night on or close to all boxes in high value districts; they shall be provided with key in lock, glass panel door or keyless self-acting door. For conspicuousness: a. Use 1/20 Deficiency Scale for high value district considered, b. Add 1/20 Deficiency Scale for other districts, c. Add for each 10 per cent, not adapted to prompt turning in of alarms, 1 point.
- Condition and Tests of Boxes.—Boxes shall be maintained in good operative condition. They shall be tested monthly and after electrical storms; tests to include visual inspection, operation, cleaning and repairing; condition of boxes shall be used in judging of thoroughness of tests. F’or condition of boxes and adequacy of tests: Use 1/10 Deficiency Scale.
- Box Distribution.—Proper distribution of boxes requires a public box, or a private box accessible to the public, within at least 500 feet of every building in mercantile and manufacturing districts, and 800 feet of every important group of buildings elsewhere. F’or numerical deficiency of boxes: a. Use J4 Deficiency Scale for high value district considered. b. Add 1/5 Deficiency Scale for other districts.
- Tests and Records.—(Except box tests.) Circuits at Headquarters to be tested three times daily in automatic, and twelve times daily in manual systems; also frequently in wind and electrical storms. Test for grounds, breaks and current strength. In manual systems, insulation resistance to be tested weekly. Battery cells to be tested for voltage and electrolyte, weekly. Office circuits 3 to 12 times daily. Circuits to be examined monthly and after wind or sleet storms. Complete records to be kept of tests, of apparatus and layout of system and of all troubles. Condition of system to be used in judging of thoroughness of tests, a. For frequency and adequacy of tests: Use 1/20 Deficiency Scale, b. For Records, add 1/20 Deficiency Scale.
- Speed of Alarms.—Speed of boxes and of alarm transmission shall not be less than 1 stroke per second in automatic and 2 strokes per second in manual systems. Tower bells, if necessary, to be operated on separate circuits, so as not to delay the operation of the system. Speed of Alarms: a. Slow, 5 points, b. Very slow, 10 points.
21 to 26. Telephone alarms shall be transmitted in all cases to the same place, with someone on duty at all times. Means to be provided in same room for transmitting telephone alarms over the fire alarm system as box alarms. At least one circuit from each telephone exchange to be reserved for fire calls; for cities having more than 5 fire stations, there shall be a private switchboard with separate circuit to each fire station, with provision permitting stations to be communicated with by the operator simultaneously or in groups.
- Telephones in fire stations: F’or each 10 per cent, deficient, 3 points.
- Telephone fire alarms transmitted from public exchange to any company called, 20 points. Or, b. Telephone fire alarms transmitted from public exchange simultaneously to all stations, 10 points. 23. No circuit from exchange reserved for fire calls, 10 points. 24. Multi-party lines to fire stations, 5 points. 25. No provision permitting communication to fire stations simultaneously or in groups by the chief or fire alarm operator, 5 points.
Telephone fire alarms not transmitted as box alarms, 20 points.
From the standpoint of fire protection, the duties of the police are the discovery of fires and the sending of alarms, the preserving of order at fires, and the reporting of buildings under construction without permit. Adequate service requires a proper signalling and/or telephone system. Municipalities of over 2,000 population should have an adequate number of patrolmen on duty day and night, and if over 15,000 population should have sufficient wagons and ropes and a signalling system.
- Co-operation with fire department: a. Fair, 10 points, b. Poor, 20 points.
- Insufficient wagons: (1 for each precinct station is considered sufficient), 10 points.
- No signalling nor telephone system, 10 points.
- Co-operation with building department poor, 10 points.
Note.—Where no police force is maintained, but is required, grade Items 1 and 4 as poor; if a Fire Police force is maintained, do not consider Items 2 and 3, and use J4 deficiency under Item 1.
Adequate building laws, either State or Municipal, shall be enacted. There shall be prescribed fire limits, including all closely built mercantile and manufacturing districts and surrounding blocks on all sides which constitute an exposure to the district or within which new construction of a mercantile or manufacturing character is developing; within these limits, frame construction shall be prohibited. Proper restrictions shall be made for heights and areas, requirements for protection to vertical and horizontal openings of all kinds, thickness of walls, private lire protection, chimneys and heating devices, etc., as given in the National Board Building Code. Wooden shingle roofs shall be prohibited throughout the municipal limits. A properly qualified official shall be in charge, with a requisite number of assistants. Proper records of building permits and operations and inspections shall be kept.
Note.—When enforcement of laws relating to any of Items 1, 2 or 3 is inadequate, grade for deficiency as for inadequate laws; the total under any sub-item for both lack of requirement and lack of enforcement not to exceed the points given.
- Fire limits: For each 10 per cent, of area inadequate, 5 points.
- Laws in regard to the following subjects inadequate or not enforced: a. Heights, 10 points, b. Areas, 10 points, c. Protection to exposed windows, 10 points, d. Protection to vertical openings, 10 points. c. Protection to communications through fire walls, 8 points, f. Frame construction in fire limits, 10 points, g. Wall thicknesses, 10 points, h. Chimneys and heating apparatus, 10 points, i. Improved construction, 5 points. j. Private fire protection, 5 points, k. Provisions for fire stops, 5 points. 1 . Provisions for fire escapes, 2 points, m. Provisions for parapets, 3 points, n. Provisions for quality of materials and workmanship, 2 points. Total, 100 points.
- Wooden shingles permitted: For each 10 per cent, of area, 4 points. Omit farm lands or other territory not subject to building operations; use as basis approximately the area covered by water distribution system.
- Records: a. Poor, 5 points, b. None, 10 points.
EXPLOSIVES AND INFLAMMABLES.
The passage of laws, either State or Municipal, on this subject and proper enforcement produce immediate results. This subject includes inflammable fluids and their compounds, explosives of all kinds and the care of combustible rubbish of all kinds. Requirements should conform to the suggested ordinances and regulations issued by the National Board of Fire Underwriters. Enforcement shall be strict, and frequent inspections shall be made; the most approved method of inspection is through the members of the fire department:
1.Laws deficient or not enforced as affecting:
- Inflammable Liquids of Class I, 20 points.
- Inflammable Liquids of Class II, 15 points.
- Inflammable Liquids of Class III, 5 points.
- Hazardous Chemicals, 10 points, e. Gases (including Acetylene and Carbide), 15 points, f. Garages, 15 points, g. Dry Cleaning, 10 points, h. Nitro-Cellulose and Films, 10 points, i. Motion Picture Machines and Booths, 5 points. j. Explosives, 20 points. k. Fireworks, 5 points. 1. Matches, 5 points. m. Combustible F’ibrcs, etc., 10 points, n. Lumber and Packing Materials, 5 points, o. Rubbish, Trash, Ashes, Bonfires, etc., 20 points, p. Definite requirement for Inspection of Premises, 10 points. Total, 180 points.
Note.—When enforcement of the laws relating to any of the above sub-items is inadequate, grade for deficiency as for inadequate laws, the total under any sub-item for both lack of requirement and lack of enforcement not to exceed the points given. Where very inadequate or no laws, but inspections are made, apply deficiency according to conditions found, but not less than ½ the points for each sub-item.
2.Records, a. Poor, 10 points, b. None, 20 points.
The National Electrical Code is the generally recognized standard for electric wiring. Its adoption by ordinance is of first importance; the laws should also provide that current shall not be furnished until the installations have been inspected and approved. The results may be obtained through enforcement by a properly qualified official; however, good results may be obtained under insurance inspection backed by a city ordinance.
- Laws: a. Slightly inadequate, 5 points, b. Moderately inadequate, to points, c. Very inadequate or none, 20 points. Note: If National Electrical Code is not enacted, hut is enforced by ruling of the inspector, grade not better than “Moderately inadequate. If enacted, but not enforced, grade as for inadequate laws.
- New inside work: a. F’air condition, 5 points, b. Poor condition, 10 points, c. Very poor condition, 20 points. Note: To be judged from condition of installations. Where municipality docs not exercise control and there is no agreement between underwriters and local electric, light company, grade not better than “Poor.”
- Old inside work: a. Fair condition, 10 points, b. Poor condition, 20 points. If reinspections are being made, use ½ points.
- Ordinance deficient: Use 1/10 Deficiency Scale. Items 5, *>, 7 and 8 to apply only for the district considered. To be figured for per rent, of street length covered, on basis of total street length in the district, including bounding streets.
- Telephone and other signalling wires not underground: I’se 1/10 Deficiency Scale.
- Light, power and trolley feed wires not underground: Use 1/10 Deficiency Scale.
- Trolley wires present in streets less than 80 feet wide: I’se 1/10 Deficiency Scale.
- Aerial distribution of service wires, 10 points.
There shall be an ordinance, or a provision in the franchise, requiring all outside wires, except trolley wires, but including trolley feeders, to be underground in closely built mercantile and/or manufacturing districts, and all such wires in the designated sections shall be properly installed underground. Overhead trolley wires in streets Under 80 feet wide in closely built sections form hindrance to the raising of ladders.
NATURAL AND STRUCTURAL CONDITIONS.
This schedule is designed to be applied to any mercantile or manufacturing district; in the smaller cities it is to be applied to the principal mercantile district, but in larger cities a separate grading may be desirable for each distinctive high value district. Item 1 applies to the entire city; all other items apply only to the district considered. In bounding a district, streets and alleys, sometimes extended, railroads and natural features will be used where practicable and every block or part block shall be included in which approximately 1/8 of the area is of the same general class as the district. Narrow streets, inaccessibility of buildings, congestion of the district and of the individual blocks, poor general structural conditions and exposures from surrounding sections all increase the probability of sweeping fires. Buildings of fireproof construction, sprinkled brick buildings, fire breaks, fire barriers and separate high pressure fire systems designed to deliver capacity at 90 pounds hydrant pressure or more, form important mitigating features.
- Street Lavements.—All streets in closelybuilt sections of the city, approximately the district covered by the water distribution system, to be paved and in good condition. Macadam or similar pavements are satisfactory in residential districts. For each 10 per cent, not paved and/or in poor condition, 10 points.
- Street Widths in District.—A through passageway, more than 20 feet in width, shall be considered as a street, a. For each 10 per cent, of total length 50 feet wide or less, 5 points, b. Add for each 10 per cent, of total length under 80 feet wide, 5 points. Do not apply b if no deficiency under Item 6.
- Accessibility of Blocks.—A block shall be considered inaccessible in proportion to the number of buildings which have only one side accessible from a street, alley, driveway or courtyard and other open spaces readily accessible from the street. All streets, as defined under Item shall be considered as forming block boundaries. For per cent, of blocks inaccessible: Use 1/10 Deficiency Scale.
- Per Cent, of Area of District in Streets and Open Spaces: 50 per cent, or over, 0 points. 40 per cent.. points. 80 per cent., 40 points. 20 per cent.. 70 points. 10 per cent., 100 points.
- Per Lent, of Block Area (including Alleys) Built Upon: 50 per cent, or less, 0 points. 60 per cent., 10 points. 70 per cent., 25 points. 80 per cent., 45 points. 90 per cent., 70 points. 100 per cent., 100 points.
- Heights of Buildings: a. Frame buildings 4 stories and over: For per cent, of total number of buildings, use 2 times Deficiency Scale, b. Frame buildings 6 stories and over: For per cent, of total number of buildings, add 4 times Deficiency Scale, c. Non-fireproof buildings (except frame) 4 stories and over: For per cent, of total number of buildings, add ¼ Deficiency Scale, d. Non-fireproof buildings (except frame) 6 Storits and over: For per cent, of total number of buildings, add full Deficiency Scale.
- Large and Excessive Areas (other than frame), but including communicating areas without standard protection: a. Unsprinklered non-fireprof areas exceeding 5.000 square feet and unsprinklered fire-proof areas or sprinklered non-fireproof areas exceeding 10,000 square feet: For per cent, of total builton area, use ½ Deficiency Scale. b. Unsprinklered non-fireproof areas exceeding 10,000 square feet and unsprinklered fireproof areas or sprinklered non-fireproof areas exceeding 20,000 square feet: For per cent, of total built-on area, add full Deficiency Scale, c. Unsprinklered non-fireproof areas exceeding 20,000 square feet and unsprinklered fireproof areas or sprinklered non-fireproof areas exceeding 40,000 square feet: For per cent, of total built-on area, add full Deficiency Scale.
- Party and Fire Walls.—Walls shall be of standard thickness, as given in the National Board Building Code. a. Party or fire walls 4 inches or more less than standard: For each 10 per cent., 2 points, b. Party or fire walls in poor condition or 8 inches less than standard: Add, for each 10 per cent., 5 points.
- Floor Openings.—Standard protection shall be provided on all communications between stories. Buildings, other than frame, with unprotected openings: For each 10 per cent, of total number of buildings, 5 points.
- Exposed Openings.—Openings in exterior W’alls, if exposed within 50 feet, shall be protected in a standard manner: Buildings, other than frame, with openings exposed and not protected: For each 10 per cent, of total number of buildings, 8 points.
- Frame Areas: a. Frame areas of all sizes, including sheds and porches: For per cent, of total built-on area, use full Deficiency Scale, b. Unsprinklered frame areas exceeding 5,000 square feet, and sprinklered frame areas exceeding 10,000 square feet:’ F’or per cent, of total built-on area, add full Deficiency Scale, c. Unsprinklered frame areas exceeding 10,000 square feet, and sprinklered frame areas exceeding 20,000 square feet: For per cent, of total built-on area, add full Deficiency Scale, d. Unsprinklered frame areas exceeding 20,000 square feet, and sprinklered frame areas exceeding 40,000 square feet: For per cent, of total built-on area, add twice Deficiency Scale.
- Permanent Awnings: For per cent, of street frontage covered: Use 1/10 Deficiency Scale.
- Conflagration Breeding Blocks.—When any blocks in a district have a hazard distinctly greater than normal for the district, a deficiency shall be applied. Where such blocks adjoin, a further deficiency shall be applied, if the separating space is less than 100 feet wide. a. For each block, 5 points, b. Add for each group of two or more adjoining blocks, 4 points, c. Add for each additional adjoining block in excess of two in each group, 3 points.
- Exposures to District.—In considering exposures, the prevailing direction of winds and the prevalence of frame construction and wooden shingle roofs in the exposing sections and the linear extent of the exposure must be taken into account. Consider each of the four sides of the district separately. When the district under consideration is subdivided by fire breaks or barriers, apply exposures of the largest subdivision, a. Mild exposure, 5 points, b. Moderate exposure, 10 points, c. Severe exposure, 15 points, d. Very severe exposure, 20 points. Add points of exposure of the four sides.
21. Superior Construction and Protection: For each 2 per cent, of built-on area covered with sprinklered or unsprinklered fireproof, sprinklered mill or sprinklered joisted brick, deduct 5 points.
22. Area of District (or largest subdivision).—An undivided area increases somewhat the possible extent of a sweeping fire. In general. it is estimated that the district hazard decreases as the undivided area is less than one mile square. Fire breaks and barriers subdividing a district will include: Rivers, parks, streets, railroad tracks, unoccupied territory, railroad embankments and similar structures, and groupings of mutually supporting fireproof or sprinklered structures which effectively subdivide a district. Fire breaks to be recognized as effectively subdividing a district shall have a total width of at least 150 feet. Deduct as follows: Area of District or of Largest Subdivision: 640 acres or more, 0 points. 500 acres, 4 points. 400 acres, 10 points. 300 acres, 20 points. 200 acres, 32 points. 100 acres, 52 points. 50 acres, 68 points. 10 acres or less, 80 points.
23.High Pressure Fire System.—A high pressure fire system may have gravity supply, direct pumpage supply or a combination of the two. It may be a separate system for fire service only, or may be the extension of a High service domestic supply into a Low service area, in which latter case only 2/3 the total fire flow shall be assumed as available capacity. To be standard, it must comply fully with the various items of adequacy and reliability listed hereinbefore under Water Supply and be capable of delivering full fire flow required about any block at a residual pressure of not less than 150 pounds. Hydrants to be of ample dimensions, with 4 independently gated hose outlets and with 8-inch gated connections to the mains; to be so distributed that the entire area of the district is protected and the average area served per hydrant shall not exceed 40,000 square feet. a. F’or each 10 per cent, of adequacy and reliability of the high pressure system at 150 pounds pressure, deduct 5 per cent. of . the total points under Natural and Structural conditions (after deducting Items 21 and 22). Or, b. For each 10 per cent, of adequacy and reliability at 120 pounds, deduct 2 per cent. Or, c. For each 10 per cent, of adequacy and reliability at 90 pounds, deduct 1 per cent.
Note: The percentage of adequacy and reliability to be determined as under water supply, and to be based on a possible total deficiency of 1,700 points.
Adverse Climatic Conditions.^—Items 1, 2, 3 and 4 to be based on average conditions for at least a 10-year period, if available. Where no weather bureau station is located in the city, use the average for the closest two or three stations.
- Winds of 25 miles velocity or over: F’or each 4 times yearly in excess of 60 times per year, 1 point.
- Snowfall in excess of 10 inches per month: For each month per year, 5 points.
- Severe Cold Weather: Apply only for the months having an average of 10 days or more with a maximum temperature of 32 degrees. For each day having a maximum temperature of 32 degrees or less, 1 point.
- Hot Dry Weather: Apply only for the months having an average mean maximum temperature of 65 degrees or more, with an average of 6 or less days of .01 inch or over of precipitation. Deficiency to be based on m t the formula. -=:Points of deficiency.
m=Average number of months per year. t=tAverage monthly mean maximum perperature. d=Average number of days per month with .01 inch precipitation.
Difference in Grading of Water Supply and Fire Department.—Where the fractional classes corresponding to the points of deficiency of the water supply and fire department, that is, the points of deficiency divided respectively by 170 and 140, differ by 3 classes or more, there shall be added to the total points of deficiency a certain number of points varying with the amount of divergence between the classes of the two features. The number of points to be added shall be determined by the following table, proportioning for fractional divergence in classes.