Operation and Calibration of Friability Test Apparatus SOP

SOP of Friability Test Apparatus

  • SOP Covers below points:
    • Precautions
    • Operation of Friability Test Apparatus
    • Calibration of Friability Test Apparatus
    • Friability Test Apparatus Calibration format
  • To provide a standard operating procedure for Operation and Calibration of Friability Test Apparatus.
2.0 SCOPE :
  • This procedure is applicable to DBK Friability Test Apparatus.
  • Quality control Chemist and above
  • Quality Control Head

Friability is the % loss in weight of a specified quantity of tablets when subjected to mechanical shock or attrition in a suitably designed apparatus. This is applicable to Uncoated Tablets.


  • Handle the acrylic drum with care.
  • Do not try to remove the drum when instrument is ON.
  • Tighten the knob of the drum properly before starting the Friability Test Apparatus.
  • Align the drum marking with that of screw to avoid the error in counting.
  • Ensure the Instrument is clean and Calibrated before proceeding.


  • Switch the MAINS power ON.
  • Weigh tablets equivalent to 6.5 gm whose average weight is equal to or less than 650 mg and note the weight in calculation sheet.
  • Take 10 tablets whose average weight is more than 650 mg and note the weight in calculation sheet.
  • Remove the acrylic cover of the drum and place the tablets inside the drum.
  • Replace the cover and tighten with the help of plastic knob.
  • Ensure the digital display indicates 0000, if not – press Reset.
  • To set the required rotation (as per Standard Test Procedure), Press ’SET’ switch.
  • Yellow LED will glow.
  • Set the rotation by ‘UP’ & ‘DOWN’ switch provided on the front side of the Friability Apparatus.
  • Press START switch after rotation is set.
    • Green coloured LED will glow and yellow LED will turn OFF.
    • Machine starts with rotation of drum.
    • Digital display increments with each rotation till equal the set number.
    • Machine stops when set and displayed rotation become equal.
    • Alarm will sounds and red coloured LED will glow.
    • Reset alarm with STOP switch.
  • Remove the tablet from the drum, weigh and note the weight in calculation sheet.
  • Remove the broken tablets and do not consider for weighing.
  • Calculate the friability (loss of weight in %).
    • Friability  = (A – B) x 100 / A
      • Where,
      • A = initial weight of tablets in gm.
      • B = weight of unbroken tablets in gm after the rotation completed.
  • Acceptance criteria for friability of uncoated tablet are not more than 1.0%.
  • If obviously cracked, chipped or broken tablets are present in the sample after rotation, the sample fails the test.
  • Inform to Quality Control Head in case of sample fails the test.

Note: Generally, the test is run once. If the results are difficult to interpret or if the weight loss is greater than the targeted value, the test is repeated twice and the mean of the 3 tests determined. A maximum loss of mass (obtained from a single test or from the mean of 3 tests) not greater than 1.0 % is considered acceptable for most products.


  • Ensure that Friability Test Apparatus is clean and free from dust.
  • Switch “ON” the main supply.
  • Set the 100  rotation as mentioned above.
  • Press START switch.
  • Observed the rotation per mentioned minutes using calibrated stop watch.
  • Note the observed rotation in format for calibration of Friability Apparatus.
    • The rotations of drums observed manually should be within tolerance limit.
Sr. No.Time in minutesRotations setTolerance
11.025+ 1
22.050+ 2
34.0100+ 4

  • FREQUENCY : Quarterly
AbbreviationExpanded form
LEDLight Emitting Diode

Annex. No.    Title
01Calibration of Friability Apparatus

  • Manual of Friability Apparatus
  • British Pharmacopoeia



Annex. No. 01 Calibration of Friability  Apparatus