BEICK KOADS. 39 



ACCEPTANCE AND REJECTION OF MATERIAL. 



Item 15. Basis of acceptance or rejection. — Paving brick sliall not be judged 

 for acceptance or rejection by the results of individual tests, but by the average 

 of not less than five tests. Where a lot of brick fails to meet the required 

 average it shall be optional with the buyer whether the brick shall be definitely 

 rejected or whether they may be regraded and a portion selected for further 

 test as provided in item 16. 



Item 16. Range of fluctuation. — Some fluctuation in the results of the rattler 

 test, both on account of variation in the brick and in the machine used in 

 testing, are unavoidable, and a reasonable allowance for such fluctuations should 

 be made wherever the standard may be fixed. 



In any lot of paving brick, if the loss on a test computed upon its initial 

 weight exceeds the standard loss by more than 2 per cent, then the portion 

 of the lot represented by that test shall at once be resampled and three more 

 tests executed upon it, and if any of these three tests shall again exceed by 

 more than 2 per cent the required standard, then that portion of the lot shall 

 be rejected. 



If in any lot of brick two or more tests exceed the permissible maximum, 

 then the buyer may, at his option, reject the entire lot, even though the average 

 of all the tests executed may be within the required limits. 



Item 17. Fixing of standards. — The percentage of loss which may be taken 

 as the standard will not be fixed in these regulations, and shall remain within 

 the province of the contracting parties. For the information of the public the 

 following scale of average losses is given, representing what may be expected 

 of tests executed under the foregoing specifications : 



General 



average 



loss. 



Maximum 



permissible 



loss. 



For brick suitable for heavy traffic . . . 

 For brick suitable for medium traffic. 

 For brick suitable for light traffic 



Per cent. 

 22 

 24 

 26 



Per cent. 

 24 

 26 

 28 



Which of these grades should be specified in any given .district and for any 

 given purpose is a matter wholly within the province of the buyer, and should 

 be governed by the kind and amount of traffic to be carried, and the quality 

 of paving brick available. 



Item 18. Culling and retesting. — ^Where under items 15 and 16 a lot or 

 portion of a lot of brick is rejected, either by reason of failure to show a low 

 enough average test or because of tests above the permissible maximum, the 

 buyer ♦may at his option permit the seller to regrade the rejected brick, sep- 

 arating out that portion which he considers at fault and retaining that which 

 he considers good. When the regrading is complete the good portion shall 

 be then resampled and retested, under the original conditions, and if it fails 

 again either in average or in- permissible maximum, then the buyer may 

 definitely and finally reject the entire lot or portion under test. 



Item 19. Payment of cost of testing. — Unless otherwise specified, the cost 

 of testing the material as delivered or prepared for delivery, up to the pre- 

 scribed number of tests for valid acceptance or rejection of the lot, shall be 

 paid by the buyer. (See also item 23.) The cost of testing extra samples 

 ma(Je necessary by the failure of the whole lot or any portion of it shall be 

 paid by the seller, whether the material is finally accepted or rejected. 



