MIL-HDBK-1028/3
contaminated parts may be moved from workbench to parts washer without being
removed from the ventilated control zone.
Ventilation System
5.5.3
5.5.3.1
Otto Fuel II Handling. The Otto Fuel II handling rooms must have
an integrated ventilation system which simultaneously exhausts contaminated
air and supplies fresh air. The design of the ventilation system should
prevent Otto fuel II fumes from reaching the breathing zone of the operators.
A negative pressure with respect to outside and clean areas is
required to prevent the spread of fumes outside of the fueling and defueling
room. The negative pressure range should be 0.05 - 0.10 in H 2O (12 - 24 Pa)
gauge.
5.5.3.2
Air Supply System. The design supply air quantity should be 90
percent of exhaust air quantity to provide the negative pressure in the room.
Supply air should be heated or cooled and filtered to provide 68 to 74 F
(20 to 23 C) space temperature. Exhaust air fan and supply air fan systems
should be interconnected so that both units work as an integrated system.
Supply air should be introduced to the room in a laminar flow arrangement,
either by a supply air plenum on one wall, withperforated metal sidewall air
outlets and exhaust system components on opposite wall, or by a supply of air
through perforated ceiling air panels with exhaust system components along
side walls. The first alternative is the better method and is recommended.
By sizing perforated air outlets for reasonably low air velocity, the
designer can reduce probability of drafty conditions in the room and maintain
the proper crossflow ventilation in the work area.
Exhaust System. The exhaust fan shall be located outside of the
5.5.3.3
outlet height should be 1-1/2 times the building roof height measured from
grade. When hills or buildings obstruct natural airflow, increase the stack
outlet height to two times the building roof height measured from grade. The
exhaust stack should be a no-loss design as shown in ACGIH, Industrial
Ventilation. Manual of Recommended Practice. All exhaust system components
exposed to the Otto fuel II fumes should be fabricated of stainless steel
(Type 316 recommended) and welded construction. Both the supply air fans and
exhaust fans should be of the backward, curved blade, nonoverloading type,
and Class II.
5.5.4
Hood Retirements. Hoods shall be designed in accordance with
ACGIH, Industrial Ventilation, Manual of Recommended Practice, to fit each
operation. Designs for the following items should be similar to the facility
plates in Appendix A:
a)
Floor hoods or floor ventilators
b) Bench ventilator
c)
Parts washer
All exhaust ducts and hoods shall be stainless steel material
(Type 316 recommended) and welded construction. All hood slots should be
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