FUME HOODS

TM 5-6640-214-14

b. Operation.

(1) Raise hinged cover and open center door to make pressure gages available for testing procedures.

(2) Fill bath, and connect to electric power.

(3) Connect condensers and place thermometer in position.

(4) Remove bombs from cabinet and prepare them for testing procedures.

(5) In order to perform oxidation stability tests, an oxygen cylinder (Units No. 47 and 48) must be used. For

detailed directions on assembling apparatus and preparing samples, and for information on testing procedures, refer to

the applicable test methods in test procedures.

WARNING

Acute poisoning by carbon tetrachloride can result in death. Its use should be prevented, if

possible. The Threshold Limit Value (TLV) established by the Occupational Safety and Health

Act of 1970 standards (29CFR1910.1000) is 10 ppm, a level which can not be detected by odor. If

used it must be contained within a laboratory hood.

c. Preventive Maintenance. Detailed instructions for cleaning apparatus are described in applicable test

procedures. Clean pressure-recorder pens when clogged, using either carbon tetrachloride or de-natured alcohol. Do not

attempt other than minor adjustments on the pressure-recording gage. Defective apparatus, especially bombs, must be

replaced.

2-22. FUME HOODS.

a. Component Parts.

Each fume hood (fig. 2-22) consists of a cabinet and electric motor with blower. The cabinet is equipped with a sliding

glass door and with gas and compressed air outlets, water and electric outlets, a blower switch, and electric cord. The

1/20-horsepower electric motor with blower is capable of exhausting 212 cubic feet (6 cubic meters) of air per minute.

Exhaust ducts are mounted in the top interior portion of the cabinet. Ducts are provided for connecting exhaust blower

opening to an outside wall of the laboratory.

b. Operations.

(1) Mount one of the fume hoods on gum apparatus cabinet (para 2-13), and mount the other hood on one of

the storage cabinets.

2-40