‫المالك‬ ‫المقاول‬

‫هيئة المجتمعات العمرانية‬ ‫شركة الجيزة العامة للمقاوالت‬

‫جهاز مدينة الفيوم الجديدة‬ ‫واالستثمار العقاري‬

‫مشروع‬
‫تصميم وتنفيذ خط طرد ومحطة رفع الصرف الصحي لعمارات اإلسكان‬
‫االجتماعي (‪ 37‬فدان) بمدينة الفيوم الجديدة‬

‫‪Ventilation Calculation‬‬
‫‪for‬‬
‫‪Wastewater Station Rooms‬‬
Generator Room
Area: 7 m * 5 m = 35 m2 , Height: 4 m,
Air Volume = 140 m3
Air Change Rate: 14

Quantity of air needed per hour = 1960 (m3/h)

Pump Room
Area: 12 m * 8 m = 104 m2
Height: 8 m
Air Volume = 832 m3
Air Change Rate: 5

Quantity of air needed per

hour = 3840(m3/h)

Operating Area
Area: 6 m * 8 m = 48 m2
Height: 6 m

Air Volume = 288

m3
Air Change Rate: 7

Quantity of air
needed per hour =
2016 (m3/h)

Quantity of air needed for Pump Room + Operating Area

per hour = 5856 (m3/h)
Medium voltage Room
Area: 8 m * 4 m = 32 m2 , Height: 4 m
Air Volume = 128 m3
Air Change Rate: 15

Quantity of air needed per hour = 1920 (m3/h)

Transformer Room # 1
Area: 4 m * 4 m = 16 m2 , Height: 4 m
Air Volume = 64 m3
Air Change Rate: 30

Quantity of air needed per hour = 1920(m3/h)

Transformer Room # 2
Area: 4 m * 4 m = 16 m2 , Height: 4 m
Air Volume = 64 m3
Air Change Rate: 30

Quantity of air needed per hour = 1920(m3/h)

S Room Name Air Selected fan No.
needed capacity m3/h
m3/h
1 Generator Room 1960 1000 2
2 Pump & Operating 5856 1000 6
Room
3 Medium voltage 1920 1000 2
Room
4 Transformer Room 1920 1000 2
Ventilation Rules of Thumb
9.06 Mechanical Rooms
A. 2 CFM/Sq.Ft.
B. Cleaver Brooks 10 CFM/BHP:
1. 8 CFM/BHP Combustion Air
2. 2 CFM/BHP Ventilation
3. 1 BHP = 34,500 Btuh
C. Mechanical Equipment Room Design Guidelines:
1. Generally, mechanical equipment rooms only require ventilation. Most mechanical
rooms are designed for 95F. to 104F; however, verify mechanical equipment
temperature
tolerances. If space temperatures below 90F. are required by mechanical equipment,
air conditioning of the space will be required.
2. If outside air is used to ventilate the mechanical room, the mechanical room design
temperature
will be 10F. to 15F. above outside summer design temperatures.
3. If conditioned air from an adjacent space is used to ventilate the mechanical room, the
mechanical room temperature can be 10F. to 20F. above the adjacent spaces.
D. ASHRAE Standard 15-1992:
1. See ASHRAE Standard 15-1992 for complete refrigeration system requirements.
2. Scope:
a. To establish safeguards of life, limb, health, and property.
b. Defines practices that are consistent with safety.
c. Prescribes safety standards.
3. Application. The standard applies to all refrigerating systems and heat pumps used in
institutional, public assembly, residential, commercial, industrial, and mixed use
occupancies
and to parts and components added after adoption of this code.
4. Refrigerant Classification is shown in the table on page 81.
5. Requirements for Refrigerant Use:
a. Requirements for refrigerant use are based on probability that refrigerant will enter
occupied space and on type of occupancy (institutional, public assembly, residential,
commercial, industrial, and mixed use).
b. The total amount of refrigerant permitted to be installed in a system is determined by
the type of occupancy, the refrigerant group, and the probability that refrigerant will
enter occupied space.
c. Refrigerant systems, piping, and associated appurtenances shall not be installed in or
on stairways, stair landings, entrances, or exits.
d. Refrigeration system components shall not interfere with free passage through public
hallways and limitations on size are based on refrigerant type.
6. Service Provisions:
a. All serviceable components of refrigerating systems shall be safely accessible.
b. Properly located stop valves, liquid transfer valves, refrigerant storage tanks, and
adequate
venting are required when needed for safe servicing of equipment.
c. Refrigerant Systems with more than 6.6 Lbs. of Refrigerant (except Group A1) require
stop valves at:
1) Suction inlet of each compressor, compressor unit, or condensing unit.
2) Discharge outlet of each compressor, compressor unit, or condensing unit.
3) The outlet of each liquid receiver.
d. Refrigerant Systems with more than 110 Lbs. of Refrigerant require stop valves at:
1) Suction inlet of each compressor, compressor unit, or condensing unit.
2) Discharge outlet of each compressor, compressor unit, or condensing unit.
3) The inlet of each liquid receiver, except for self-contained systems or where the
receiver is an integral part of the condenser or condensing unit.
4) The outlet of each liquid receiver.
5) The inlet and outlet of condensers when more than one condenser is used in parallel.
7. Installation Requirements:
a. Air ducts passing through machinery rooms shall be of tight construction and shall
have no openings in such rooms.
b. Refrigerant piping crossing an open space that affords passageway in any building
shall not be less than 7-3 above the floor.
c. Passages shall not be obstructed by refrigerant piping.
d. Refrigerant piping shall not be placed in or pass through any elevator, dumbwaiter, or
other shaft containing moving objects or in any shaft that has openings to living
quarters or to main exits.
e. Refrigerant piping shall not be placed in exits, lobbies, or stairways, except that such
refrigerant piping may pass across an exit if there are no joints in the section in the exit.
f. Refrigerant piping shall not be installed vertically through floors from one story to
another except as follow:

1) Basement to first floor, top floor to mechanical equipment penthouse or roof.

2) For the purpose of interconnecting separate pieces of equipment. The piping may
be carried in an approved, rigid and tight, continuous fire-resistive pipe, duct, or
shaft having no openings into floors not served by the refrigerating system or carried
exposed on the outer wall of the building.
8. Refrigeration Equipment Room Requirements:
a. Provide proper space for service, maintenance, and operation.
b. Minimum clear head room shall be 7-3.
c. Doors shall be outward opening, self closing, fire rated, and tight fitting. No other
openings shall be permitted in equipment rooms (except doors) that will permit passage
of refrigerant to other part of the building.
d. Group A1 refrigerants require an oxygen sensor located in the equipment room set to
alarm when oxygen levels fall below 19.5 volume percent.
e. Group A2, A3, B1, B2, and B3 refrigerants require a refrigerant vapor detector located
in the equipment room set to alarm and start the ventilation system when the level
reaches the refrigerant’s toxicity level.
f. Periodic test of alarm and sensors are required.
g. Mechanical rooms shall be vented to the outdoors.
h. Mechanical ventilation shall be capable of exhausting the air quantity determined by
the formula in Part 5, Equations. The exhaust quantity is dependant on the amount
of refrigerant contained in the system.
i. No open flames that use combustion air from the machinery room shall be installed
where any refrigerant other than carbon dioxide is used.
j. There shall be no flame producing device or continuously operating hot surface over
800F permanently installed in the room.
k. Refrigeration compressors, piping, equipment, valves, switches, ventilation equipment,
and associated appurtenances shall be labeled in accordance with ANSI/ASME A13.1.

9.07 Combustion Air

A. 1990 BOCA Code:
1. Inside Air: 1 Sq.In./1000 Btuh.
2. Outside Air:
a. 1 Sq.In./4000 Btuh without Horizontal Ducts.
b. 1 Sq.In./2000 Btuh with Horizontal Ducts.
3. 1 opening high and 1 opening low for both paragraphs 1 and 2 above. Area listed is for
each opening.
4. Mechanical Ventilation: 1 CFM/3000 Btuh.
B. 1993 BOCA Code:
1. Inside Air:
a. 40 Cu.Ft. of Room Volume/1000 Btuh.
b. 1 Sq.In./1000 Btuh; 100 Sq.In.Minimum.
2. Outside Air:
a. 1 Sq.In./4000 Btuh with out Horizontal Ducts.
b. 1 Sq.In./2000 Btuh with Horizontal Ducts.
c. 1 Sq.In./4000 Btuh for Floor, Ceiling, or Vertical Duct openings.
3. 1 opening high and 1 opening low for both paragraphs 1 and 2 above. Area listed is for
each opening.
4. Mechanical Ventilation: 1 CFM/3000 Btuh
D. Ventilation Requirements:
1. Ventilation, natural or mechanical,must be sufficient to limit the concentrations of
flammable
gases or vapors to a maximum level of 25% of their Lower Flammable Limit/Lower
Explosive Limit (LFL/LEL).
2. Minimum Ventilation Required: 1.0 CFM/Sq. Ft. of floor area or 6.0 air changes per
hour, whichever is greater. If a reduction in the classification is desired, the airflow must
be 4 times the airflow specified above.
3. Recommendation:Ventilate all hazardous locations with 2.0 CFM/Sq. Ft. of floor area
or 12 air changes per hour minimum with half the airflow supplied and exhausted high
(within 6 inches of the ceiling or structure) and half the airflow supplied and exhausted
low (within 6 inches of the floor).
4. Ventilation rate a minimum of 4 times the ventilation rate required to prevent the space
from exceeding the maximum level of 25% LFL/LEL using fugitive emissions
calculations.
5. Ventilate the space so that accumulation pockets for lighter than air or heavier than air
gases or vapors are eliminated.
6. Monitoring of the space is recommended to assure that the 25% LFL/LEL is not
exceeded.