Climatic Zones For Stability Studies

Climatic zones ich

The drug products are tested under various environmental conditions to collect data regarding the stability of drug products.

Pharmaceutical drug products are stored under various ranges of temperature & humidity & are tested to check the safety & efficacy of that drug product after a specified period of time.

The temperature & humidity of all the countries is not the same. That is why the ICH has divided the whole world into various climatic zones.

Importance Of Climatic

Stability zones play an important role in collecting stability data of a drug product.

  • One must have to collect stability data of new drug products according to the climatic zone of the country where it is going to be registered.
  • For export of a drug product in a specific country we must collect stability data according to the zone of that country.
  • Storage conditions for various pharmaceutical drug products are determined by testing the product in various climatic conditions.

Climatic Zones For Stability Studies

The world is divided into four climatic zones & zone IV is further subdivided into two zones which are IVa & IVb so by adding by division we have 5 ICH climatic zones.

The numbering of climatic zones for stability studies is given below,

  • Zone I
  • Zone II
  • Zone III
  • Zone IVa 
  • Zone IVb

The names of above mentioned climatic zones are given below

Zone  Zone Name/Climate 
Zone I Temperate
Zone II Mediterranean/


Zone III Hot Dry
Zone IVa Hot Humid/Tropical 
Zone IVb Hot Higher Humidity 

Following are the long-term stability study conditions for above mentioned ICH stability zones

Long-Term Stability Studies


Zone  Temperature  Humidity   Minimum time at submission 
Zone I 21°C ± 2% 45% RH ±5% 12 Month
Zone II 25 °C± 2% 60% RH ±5% 12 Month
Zone III 30 °C± 2% 35% RH ±5% 12 Month
Zone IVa 30 °C± 2% 65% RH ±5% 12 Month
Zone IVb 30 °C± 2% 75% RH ±5% 12 Month

Countries According To Climatic Zones

Following is the division of main countries according to their climatic zones

Name  Zone 

   Zone I

North Europe 


Name  Zone 

   Zone II



Name  Zone 

  Zone III



Name Zone 

   Zone IV


Also Read

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  2. Why Do We Use Three Batches For Validation