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FORMALDEHYDE

Formaldehyde Ppt

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Page 1: Formaldehyde Ppt

FORMALDEHYDE

Page 2: Formaldehyde Ppt

Formaldehyde is a colorless, strong-smelling gas often found in aqueous (water- based) solutions. Commonly used as a preservative in medical laboratories and mortuaries.

Page 3: Formaldehyde Ppt

Formaldehyde is also found in many products such as chemicals, particle board, household products, glues, permanent press fabrics, paper product coatings, fiberboard, and plywood.

Page 4: Formaldehyde Ppt

It is also widely used as an industrial fungicide, germicide and disinfectant. The term "formalin" is used to describe a saturated solution of formaldehyde dissolved in water, typically with another agent, most commonly methanol, added to stabilize the solution.

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Formalin is typically 37% formaldehyde by weight (40%by volume) and 6-13%methanol by volume in water. The formaldehyde component provides the disinfectant effects of formalin.

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The most common way to be exposed to formaldehyde is by breathing air containing formaldehyde. This usually occurs in indoor environments where the gas has been released from formaldehyde-containing products.

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Exposure to liquid formalin may be through the skin or by ingestion.

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EFFECTS

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INHALATION:

Eye irritation

Nose irritation

Throat irritation

Headache

Skin injury

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INGESTION:

Burnt esophagus

Burnt stomach

SEVERE CASES:Unconsciousness

Arrhythmia

Hypotension

Coma

Page 11: Formaldehyde Ppt

THE OSHA FORMALDEHYDE STANDARD

Page 12: Formaldehyde Ppt

The permissible exposure limit (PEL) for formaldehyde in the workplace is 0.75 parts formaldehyde per million parts of air (0.75 ppm) measured as an 8-hour time-weighted average (TWA).

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The standard includes a second PEL in the form of a short-term exposure limit (STEL) of 2 ppm which is the maximum exposure allowed during a 15-minute period.

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The action level which is the standard's trigger for increased industrial hygiene monitoring and initiation of worker medical surveillance- is 0.5 ppm when calculated as an 8-hour TWA.

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LABORATORY TEST

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Fuchsin Sulfurous Acid Test

Principle: SCHIFF’S REACTION

Reagents: acetaldehyde

37 % formaldehyde solution

96 % ethanol

0.01 % aqueous solution of fuchsin

sulfurous acid Schiff's Reagent (Merck)

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Positive reation: Red to purple solution