---
title: "Data Schema: Chemistry"
url: "https://help.esdat.net/en/article/data-table-definitions-chemistry-tables"
language: "en"
last_updated: "2026-10-01T15:30:19.884Z"
---
# Data Schema: Chemistry
Data Schema
Chemistry data is stored primarily in the Chemistry Samples and Chemistry Results tables.
A Chemistry Sample is typically associated with a Location and, if relevant, a Well. There will often be multiple Chemistry Samples associated with a single Location (and Well if relevant).
Chemistry Samples may also be associated with a Lab Sample Delivery Group and a Laboratory Report. Chemistry Samples are also often associated with a Monitoring Round, which can combine multiple Laboratory Reports as well as Field Data.
Chemistry Results are connected to a Chemistry Sample by having a matching SampleCode, which is unique per sample within a Project. There will typically be multiple Chemistry Results associated with a single Chemistry Sample.
## Lab Reports
| PrimaryKey | Column | Type | Description |
| --- | --- | --- | --- |
| | PID | Integer | References Projects.ID - a unique integer for each project. |
| \* | Lab\_Report\_Number | Text(25) | The Identifier for a Lab Report, as assigned by the Laboratory |
| \* | Lab\_Name | Text(40) | |
| | Project\_ID | Text(20) | Unrelated to the core Project\_ID in the system - a text field reporting the Project value used by the Lab. |
| | Date\_Reported | DateTime | |
| | Project\_Name | Text(255) | Unrelated to the core Project\_ID in the system - a text field reporting the Project value used by the Lab. |
| | Lab\_Signatory | Text(50) | Person at the lab who signed off on the results. |
| | Report\_Recipient1 | Text(255) | Name of first person who is a recipient of the Lab Report |
| | Report\_Recipient2 | Text(255) | |
| | Report\_Recipient3 | Text(255) | |
| | Documents\_ID | Integer | An integer that refers to a document in the Documents table (not editable) |
| | Reporting\_Status | Text(255) | Typically Pending, Draft or Final. Used when preliminary reports may be issued by the laboratory. |
| | Accepted | True/False | If the lab report is accepted |
| | Rejected | True/False | |
| | Accepted\_By | Text(40) | Person who accepted the Lab Report. |
| | Accepted\_Date | DateTime | |
| | Acceptance\_Comments | Text(255) | |
| | Comments | Text(500) | General comment in relation to the lab report or associated data, as distinct from Acceptance Comments. |
| | Primary Recipient Org | Text(255) | The organization that the lab report was issued to. |
## Chemistry Samples
| PrimaryKey | Column | Type | Description |
| --- | --- | --- | --- |
| | SID | Integer | References Sites.ID - a unique integer for each Site. |
| \* | PID | Integer | References Projects.ID - a unique integer for each project. |
| \* | SampleCode | Text(40) | A unique code for each sample within each Project |
| | Field\_ID | Text(50) | The ID given to the Sample in the field. |
| | Sampled\_Date\_Time | DateTime | The Date/Time at which the sample was collected. |
| | Location\_Code | Text(20) | References a Location in the Locations Table. |
| | Well | Text(10) | References a Well in the Wells table. |
| | Sample\_Depth\_From | Numeric | Top depth at which the sample was taken. |
| | Sample\_Depth\_To | Numeric | Bottom depth at which the sample was taken |
| \* | Matrix\_Type | Text(14) | Water, Soil, Sediment etc.. Available as a drop-down of valid values in the system. |
| | Sample\_Type | Text(22) | List below. Available as a drop-down of valid values in the system:
Normal,
Field\_D, (Field Duplicate)
Field\_B, (Field Blank)
Trip\_B, (Trip Blank)
Rinsate
Interlab\_D, (Interlab Duplicate)
Composite (X Samples), (Composite with X Samples)
Trip\_S, (Trip Spike)
TSC, (Trip Spike Control)
MS, (Matrix Spike)
MS\_D, (Matrix Spike Duplicate)
MB, (Method Blank)
SB, (Storage Blank)
LCS, (Lab Control Sample)
LCS\_D, (Lab Control Sample Duplicate)
SRM, (Standard Reference Material)
CRM, (Certified Reference Material)
LAB\_D (Duplicate)
LAB\_T (Triplicate)
NCP (Non-Client Parent - for duplicates or spikes from another client in the same sample analysis batch) |
| | Parent\_Sample | Text(40) | Used for Duplicate samples, populated with the SampleCode of the primary Sample. |
| | SampleComments | Text(255) | Comments related to the Sample as entered by the data reviewer. |
| | Matrix\_Description | Text(255) | A description of the Sample Matrix, such as a soil description. |
| | Sampled\_By | Text(50) | |
| | Sampling\_Method | Text(20) | |
| | Monitoring\_Round | Text(30) | Name of each monitoring round, makes extracting data that is obtained in one round over multiple dates easier. |
| | SDG | Text(50) | Sample Delivery Group - a batch of samples received at a laboratory. Often the COC Number is used to identify the SDG.
Typically left blank for historical data imports. |
| | Lab\_Name | Text(40) | If either Lab Name or Lab Report Number is populated they must both be populated. |
| | Lab\_Report\_Number | Text(25) | Lab Report Number as issued by the Laboratory. |
| | Lab\_SampleID | Text(20) | Sample Identifier as used within the lab. |
| | Lab\_Comments | Text(255) | Comments related to the Sample as provided by the lab. |
| | Odour\_Ranking | Text(30) | Field Description of any odor related to the sample |
| | Env\_Stds\_Conditional\_Matrix\_Type | Text(14) | A specific matrix type that applies to this sample for the purposes of comparing with conditional environmental standards. |
| | Location Visit | Integer | References Location\_Visits.ID - a unique integer for each Location Visit. Relevant only for field samples collected in the ESdat Field Portal / App. |
| | Equipment\_ID | Text(40) | Identifier for equipment used in the sampling |
| | Equipment\_ID2 | Text(40) | Identifier for equipment used in the sampling |
| | Field\_Sample | Text(40) | Used for lab samples, populated with the SampleCode of the corresponding Field Sample. |
## Chemistry Results
| PrimaryKey | Column | Type | Description |
| --- | --- | --- | --- |
| \* | PID | Integer | References Projects.ID - a unique integer for each project. |
| \* | SampleCode | Text(40) | A unique code for each sample within each Project. It must match a value in the Chemistry Samples table for the same Project. |
| \* | ChemCode | Text(20) | A unique code (CAS Number where possible) that identifies each compound |
| | OriginalChemName | Text(70) | The name of the analyte in the original source data.
Note, in ESdat the name used for outputs for each ChemCode can be configured and standardised in the Chemistry Profiles. |
| | Prefix | Text(3) | < (for non-detects) or > (for greater than) |
| | Result | Numeric | Numeric Results |
| | Text\_Result | Text(255) | For use when a result is not numeric. |
| | Result\_Unit | Text(15) | Units a Numeric Result is reported in. |
| \* | Total\_or\_Filtered | Text(1) | T or F to indicate if a Sample is filtered in the field. |
| \* | Result\_Type | Text(20) | One of the following values:
Reg(regular result)
Calc (calculated result)
leached\_REG (regular leached results)
SUR (Surrogate)
leached\_SUR (leached surrogate)
SC (Spike Compound)
SCD (Spike Compound Duplicate) |
| | Method\_Type | Text(50) | The type of method, typically matches requests on COC forms. |
| \* | Method\_Name | Text(90) | The method used to obtain the result, used for laboratory results |
| | Extraction\_Date | DateTime | Date/Time the extract was obtained from the samples, for lab results. |
| | Extraction\_Method | Text(255) | Lab Method used for extraction prior to analysis |
| | Analysed\_Date | DateTime | Date the results were analysed if lab data. |
| | EQL | Numeric | Effective Quantitation Limit reported in the units specified in the Detection Limit Units column. |
| | MDL | Numeric | Method Detection Limit |
| | RDL | Numeric | Reportable Detection Limit |
| | ODL | Numeric | Other Detection Limit, for use if required in contract or client specific requirements such as the US Defense “Limit of Detection”. |
| | Detection Limit Units | Text(15) | Units the above Detection Limits are reported in. |
| | Lab\_Comments | Text(500) | Comments specific to a result as provided by the Laboratory. |
| | Lab\_Qualifier | Text(20) | |
| | UCL | Numeric | Upper Confidence Limit, for lab data QA |
| | LCL | Numeric | Lower Confidence Limit, for lab data QA |
| | Dilution\_Factor | Numeric | Populated during the import of Lab Reports to indicate sample dilution prior to analysis. |
| | Spike\_Concentration | Numeric | Lab QA Spike Concentration |
| | Spike Measurement | Numeric | Lab QA Spike Measurement |
| | Spike Units | Text(15) | Units for the Spike Concentration and Measurement. |
| | Lab\_Preperation\_Batch\_ID | Text(255) | A lab identifier for samples included in a preperation batch |
| | Lab\_Analysis\_Batch\_ID | Text(255) | A lab identifier for samples included in an analysis batch |
| \* | Lab\_Analysis\_ID | Text(255) | A lab identifier for a specific analysis. |
| | Validation\_Comments | Text(500) | Comments from the person who has validated the data. |
| | Validation\_Qualifier | Text(5) | Qualification code from the person who has validated the data. |
| | Final\_Comments | Text(500) | The Comments to be presented in the final report. |
| | Final\_Qualifier | Text(5) | The Qualifier to be presented in the final report. |