Dedicated To Sir Ahmed Shah

Friability Test ~ Quality Control Management For Tablets

Wednesday, May 16, 2012

Friability Test

“FRIABILITY is the phenomenon where the surface of the tablet is damage or shown a site of damage due to mechanical shock.”

PURPOSE: To evaluate the ability of the tablets to withstand the breakage during the transportation and handling.

Roche friabalitor consist of a drum which have an internal diameter between 283 and 291 mm and a depth between 36 and 40 mm, of transparent synthetic polymer with polished internal surfaces, and subject to minimum static build-up (see figure for a typical apparatus). One side of the drum is removable. The tablets are tumbled at each turn of the drum by a curved projection with an inside radius between 75.5 and 85.5 mm that extends from the middle of the drum to the outer wall. The outer diameter of the central ring is between 24.5 and 25.5 mm. The drum is attached to the horizontal axis of a device that rotates at 25 ±1 rpm. Thus, at each turn the tablets roll or slide and fall onto the drum wall or onto each other.


For tablets with a unit weight equal to or less than 650 mg, take a sample of whole tablets corresponding as near as possible to 6.5 g. For tablets with a unit weight of more than 650 mg, take a sample of 10 whole tablets.


The tablets should be carefully dedusted prior to testing. Accurately weigh the tablet sample, and place the tablets in the drum. Rotate the drum 100 times, and remove the tablets. Remove any loose dust from the tablets as before, and accurately weigh.

Generally, the test is run once. If obviously cracked, cleaved, or broken tablets are present in the tablet sample after tumbling, the sample fails the test. If the results are difficult to interpret or if the weight loss is greater than the targeted value, the test should be repeated twice and the mean of the three tests determined. A maximum mean weight loss from the three samples of not more than 1.0% is considered acceptable for most products.

Effervescent tablets and chewable tablets may have different specifications as far as friability is concerned. In the case of hygroscopic tablets, an appropriate humidity-controlled environment is required for testing.

PRECENTAGE OF FRIABILITY of the tablets of a badge can be find by the following formula:

Percentage Friability = W1 – W2/W1 × 100

Where, W1 = weight of tablets before testing

W2 = weight of tablets after testing.


According to B.P = Percentage of friability should be not more than 0.8%.

According to U.S.P = Percentage of friability should be not more than 4%


  1. The formula given above for % friability seems not right....Percentage Friability = W1 – W2/W1 × 100
    It should be Friability = 100(W1 – W2)/W1

  2. it rather should be 100*[(W1 – W2)/W1]

  3. According to usp % of friability should be not more than 1%