1) Ammonia is a colorless gas with a pungent odor that dissolves readily in water to form ammonium hydroxide. It is widely used industrially as a catalyst and reagent. 2) Its main uses are as a refrigerant and in manufacturing fertilizers. When released from storage as a liquid under pressure, it can rapidly cool to form a dense cloud near the ground. 3) Exposure can cause irritation at low levels and life-threatening burns, respiratory distress, and even death at higher concentrations. Symptoms depend on the level and duration of exposure.

1. Ammonia NH3
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 cooling to form a dense cloud
that hugs the ground.
Toxic Effects:- Acute:- 1) Smell felt at 30-50 ppm. At this ppm there is irritation of Eyes &
Mucous Membrane of Respiratory Tract.
2) Upto 500 ppm:- Cough, Hoarseness of Voice 7 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 & Cornea
b) Laryngeal Edema
c) Pulmonary Edema
d) Broncho Pneumonia
e) Hoarseness & Dyspnoea
f) Death due to b,c&d
Laryngeal Spasm:- This is peculiar in Ammonia. Laryngeal Spasm &
Spasm of Glottis are frequent. This can produce Asphexia & Death, but
spasmwill relief if the person becomes Unconscious.
4) Effect on Eyes:- Ophthalmic complications like a) Corneal Opacity
b) Cataract Formation c) Glocoma
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.
Treatment:- Symptomatic.