How to understand aboout Uncertainty value in CRM Certificate

[namlexuannth]

Dear All*
I post to seek your consultance/experiences for explaination about the Uncertainty value in the attached certificate.

Example:

Standard value (ARV) = 0.0502%
Uncertainty (U) =2

I cannot understand that U >> much more than ARV* because U value here is not defined the fomular. There fore* Does this certificate is wrong?

Could anyone understand* plesease help to share it. Especially* if you have any standard related to clear this problems* also open share it.

I'm so appreciate*

[tassoss]

Dear All*
I post to seek your consultance/experiences for explaination about the Uncertainty value in the attached certificate.

Example:

Standard value (ARV) = 0.0502%
Uncertainty (U) =2

I cannot understand that U >> much more than ARV* because U value here is not defined the fomular. There fore* Does this certificate is wrong?

Could anyone understand* plesease help to share it. Especially* if you have any standard related to clear this problems* also open share it.

I'm so appreciate*

standard value +- uncertainty value

i.e. methane 0.0502% +- 2%* can be between 0.0502 -2%=0.0492 and 0.0502+2%=0.0512

[namlexuannth]

Dear Tassoss*
Thank you for your answer*
You've speculated yourself by understanding that Uncertainty value= 2% of true value* right? because it's unreasonable if accepted Uncertainty= 2 (It will be much more larger than true value) whether absence in the description of CRM's Certificate.

But I wonder* Is this the exactly rule for all CRM Certificate? Because in some cases when you calculate under percentage of true value and use exactly itself is reasonable in both cases. What is your decision at that case?

[tassoss]

Dear Tassoss*
Thank you for your answer*
You've speculated yourself by understanding that Uncertainty value= 2% of true value* right? because it's unreasonable if accepted Uncertainty= 2 (It will be much more larger than true value) whether absence in the description of CRM's Certificate.

But I wonder* Is this the exactly rule for all CRM Certificate? Because in some cases when you calculate under percentage of true value and use exactly itself is reasonable in both cases. What is your decision at that case?

i haven't speculated anything. the stated uncertainty is always in the units of the certified value.

[link Point to another website Only the registered members can access]

[namlexuannth]

Dear my friend*
thank you for your kindly reply*
In your certificate* the Uncertainty has the unit same as the Certified value's unit* that's the good CRM Certificate* so you are easy to understand.

But my situation is different with yours. Please see in my attach certificate above (img-320141428-0001.pdf ) to instruct me properly. They are not define unit of Uncertainty* they are not defined the formula to calculate them.

Once again* thank you for your sharing experiences.