Ammonia NH3

Dr S K Haldar

Characteristics:-

• Anhydrous Ammonia is a colorless gas with a distinct pungent odour.

• It is extremely soluble in the water forming a caustic alkaline solution of ammonium hydroxide (NH4OH).

• It is one of the most widely used industrial gases as a catalyst & reagent.

Main Use:-

1) As a Refrigerant 2) To Manufacture Fertilizers• Although the gas is lighter than air it can

behave paradoxically in an accidental release from storage in liquid form under pressure by undergoing rapid cooling to form a dense cloud that hugs the ground.

Toxic Effects:-Acute:- 1) Smell felt at 30-50 ppm and there is irritation of Eyes & Mucous

Membrane of Respiratory Tract.2) Up to 500 ppm:- Cough, Hoarseness of Voice, Tightness of Throat, Eye

Irritation & Conjunctivitis like symptoms.3) 500-1,000 ppm:- It is life threatening & causes

a) Chemical Burns of Nose, Mouth, Throat & Corneab) Laryngeal Edemac) Pulmonary Edemad) Bronchopneumoniae) Hoarseness & Dyspnoeaf) Death due to b, c & d.

Toxic Effects:-Laryngeal Spasm:- This is peculiar in Ammonia. Laryngeal Spasm &

Spasm of Glottis are frequent. This can produce Asphyxia & Death, but spasm will relief if the person becomes Unconscious.

4) Effect on Eyes:- Ophthalmic complications like - a) Corneal Opacity, b) Cataract Formation, c) Glaucoma.

5) Effect on the Skin:- A jet of the Anhydrous Ammonia on the moist Skin can cause second degree burns.6) Gastritis:- It continues several months after a gasing exposure.7) The person who survives as acute gasing attack may develop permanent

Respiratory Disabilities like a) Progressive Airway Obstruction b) Decreased Diffusion Capacity c) Bronchiolitis Oblitarance d) Bronchiactasis e) Continuous Cough & Sputum.