please translate red sentence.

心情

Hardness conversion charts should be used with great caution since discrepancies of 0.3 HRC numbers at 30HRC to 3.9HRC numbers at 60 HRC, have been noted between various published conversion charts. Therefore, it is suggested that the conversion chart used for testing and reporting be specified. Some of the more popular hardness conversion charts are found in ASTM A370, ASTM E140, ISO 6336--5, and certain individual corporate documents and standards. For this document, ASTM A370 is used and should be used whenever
no other document is specified.
please translate red sentence...

hlqhlq

I agree with 2# floor.

mvp

在30HRC的时候有大概0.3HRC的误差，在60HRC的时候大概有3.9HRC的误差。并不是说是转换误差，只是这种误差是系统本身的，跟转换无关，自己用的时候要注意考虑这些误差

Hisen

MVP is right, I agree!

bill_bush

我认为，在这里没必要把这种误差（差别。。。）说得很清楚。

毕竟意见还是不能统一的，何况，这种折算也是根据计算和系统测试得到的，因此可以认为有部分系统误差和部分转换计算误差。

而且文章中并没有把这种差别归为哪一种类型。