EMSI Source Testing Department Form

o ICR Detection Limit and Reporting Policy       ST904‐01

Subject: Notice of Detection Limits and Sample Reporting

DETECTION LIMIT POLICY

EMSI will implement the following policies to maintain consistent ICR reporting of

emission results.  When reporting test results which laboratory detection limits are

provided, the following policy will be utilized in the calculations.

Use the specific sample detection limit provided by the laboratory for those samples or

fractions of samples that are below analytical detection for all calculations.  Indicate on

the sheet by placing “BDL ‐ Below the Detection Limit” next to the sample or fraction in

the spreadsheet in which the fraction or all fractions are below the detection limit.  

Indicate on the sheet by placing “ADL ‐ Above the Detection Limit” next to the sample or

fraction in the spreadsheet in which the fraction or all fractions are above the detection

limit.  Indicate on the sheet by placing “DLL ‐ Detection Level Limited” next to the

sample in the spreadsheet where some fractions are below the detection limit and some

fractions are above the detection limit.    

Blanks were conducted for each method tested and reported as supplemental data.  

EMSI did not perform any blank corrections to the results.  Blanks with detected values

must be evaluated separately from the reported results.

EPA Method 5/OTM‐028 ‐ EMSI

EMSI utilizes a reporting detection limit (RDL) of 0.5 mg for all fractions.  The 0.5 mg is

the allowable tolerance between successive weights and therefore this has been

identified by EMSI to be the minimum level of reporting.

EPA Method OTM‐027/OTM‐028 ‐ EMSI

EMSI utilizes a reporting detection limit (RDL) of 0.5 mg for all fractions.  The 0.5 mg is

the allowable tolerance between successive weights and therefore this has been

identified by EMSI to be the minimum level of reporting.

Method 26A HCl/HF – Maxxam Analytical

Method M26A DL = Adjusted volume * (mL) x 0.05 ug/mL (lowest calibration standard).  

e.g. 4000 mL x 0.05 ug/mL = 200 ug = the adjusted volume is typically 4000 mL based on

a starting impinger charge volume of 200 mL (100 + 100 for impingers 1 & 2) of 0.1N

H2SO4. The adjustment is necessary to "matrix match" the samples to the standards. If a

higher Normality is used then a higher adjusted volume will be required.  
Method‐033 HCN – Maxxam Analytical

Method‐033 DL = Adjusted volume (mL), if required x 0.1 ug/mL (lowest calibration

standard).  e.g. 200 mL x 0.1 ug/mL = 20 ug  Here the samples are analyzed as received

as long as they are 0.1N H2SO4. If a higher Normality is used then a higher adjusted

volume will be required.  

Method 0031 VOST – Maxxam Analytical

VOST results are reported at the MDL (Method Detection Limit). Method Detection

Limits are calculated by using the standard deviation from a minimum of 8 replicate low

level spikes. Each analytes standard deviation is multiplied by the appropriate Student T

value to determine the statistically derived reporting limit.  

Method 29 Metals – Maxxam Analytical

For Method 29 the analyst takes the statistically determined MDL (Method Detection

Limit) value and multiplies it by a “factor” in order to determine the RDL (Reporting

Detection Limit). This process is similar to the one employed in Method 23 where the

EDL is determined based on a constant factor of 2.5 times the signal to noise ratio.  

For the ICP/MS this “factor” can vary. The factor is determined by the analyst at the

bench and takes into account all relevant factors such as, final volumes, interferences,

matrix issues, etc. The RDL (Reporting Detection Limit) reported is the lowest

concentration that the lab feels can be reported within the 99% confidence interval. For

values below this RDL the uncertainty increases. Section 5.5.5.2.2.1 bullet H refers to

the ICP/MS procedure.

  

Method 23 Dioxin/Furan/PCB – Maxxam Analytical

Reporting limits for Method 23 are calculated on a per sample basis. The EDL (Estimated

Detection Limit) is determined based on a constant factor of 2.5 times the signal to

noise ratio as defined in Method 23/8290. This EDL value is generally less than the RDL

(Reporting Detection Limit), that is equivalent to the lowest calibration standard but in

certain cases it may be higher due to “matrix” effects. The EDL may even be less than

the statistically derived MDL (Method Detection Limit).  

Method M0010 PAH – Maxxam Analytical

PAH results are reported at the MDL (Method Detection Limit) multiplied by the number

of “splits”. Method Detection Limits are calculated by using the standard deviation from

a minimum of 8 replicate low level spikes. Each analytes standard deviation is multiplied

by the appropriate Student T value to determine the statistically derived reporting limit.  

Method M0011 Formaldehyde – Maxxam Analytical

Formaldehyde results are reported at the RDL (Reporting Detection Limit) that is

equivalent to the lowest calibration standard.
Method 30B Mercury ‐ EMSI

Mercury results are reported per EPA Method 30B.  Mercury results are reported at the

MDL (Method Detection Limit) if the results are less than the establish value including

second sections of the traps.  Method Detection Limits are calculated by using the

standard deviation from a minimum of 7 replicate low level spikes as outlined in EPA

Method 301.  The total mass of Hg measured in each sorbent trap section 1 must fall

within the lower and upper mass limits established during the initial Hg0 and HgCl2

analytical bias test.  If a sample is analyzed and the concentration is below the lowest

point in the calibration curve and above the MDL, an estimated mass or concentration

of the sample based on the analytical instrument response relative to an additional

calibration standard at a concentration or mass between the MDL and the lowest point

in the calibration curve. This is accomplished by establishing a response factor (e.g., area

counts per Hg mass or concentration) and estimating the amount of Hg present in the

sample based on the analytical response and this response factor.  

Method 3A, 6C, 7E, 10, and 25A ‐ EMSI

Instrumentation methods utilize the direct output of the analyzer regardless of

detection limits.  The analyzer response from each analyzer is corrected for drift by

conducting calibrations to the system before and after each run.  This value is reported

even if the value drifts below zero.  Calibration spans are selected based on estimated

stack values and calibration protocol 1 bottle availability.

Method 18 Methane ‐ EMSI

Methane results are reported at the MDL (Method Detection Limit) if the results are less

than the establish MDL value.  Method Detection Limits are calculated by using the

standard deviation from a minimum of 7 replicate low level spikes as outlined in EPA

Method 301.