Request stack emissions testing equipment
Fill out our form to request equipment for stack emissions testing sample collection.
Request VOCs in canister testing equipment
Fill out our form to request equipment for VOCs in air testing sample collection.
Preservation and holding times
These instructions are for samples taken for environmental testing.
The sample sizes, preservation procedures, holding times and conditions for air, aqueous and solid samples are recommendations only.
Base your decision on the nature of the sample, the intended use of the data and the data quality objectives. For example, you can use alternative storage conditions if the analyte stability within a matrix can be demonstrated and data quality objectives are not compromised.
In a given sample, the analyte requiring the most preservation treatment as well as the shortest holding time should dictate the preservation treatment of the overall sample.
General rules for samples
- Place in ice immediately after sampling.
- Cool to <4 °C.
- Deliver to NMI within 24 hours of sampling.
- Use ice bricks when dispatching by air and over long distances, and when couriers will not freight ice.
- Have at least half the recommended holding time remaining when relinquished to us.
- Avoid delivering time-critical samples to us late on Friday.
Recommendations for specific samples
Each sample type has different recommendations for storage conditions needed to preserve the sample. See our recommended preservation procedures, holding times and conditions for:
Safety data sheets
Certain substances must be labelled under the Globally Harmonized System (GHS) of classification and labelling.
We have provided:
- safety data sheets (SDS) for your information
- labels to affix to the collection bottles for water samples.