What type of container is required for samples analyzed for oil and grease?

For the analysis of oil and grease, glass containers are required because they do not leach chemicals and will not interact with the sample. This is crucial for ensuring the accuracy and integrity of the sample during analysis. Glass is inert and does not absorb or chemically react with the oil and grease, which allows for reliable measurement and prevents contamination.

Plastic containers, while lightweight and durable, can sometimes release compounds that may interfere with certain analyses. Metal containers may also chemically react with some components of oil and grease analytes, possibly leading to skewed results. Cardboard is inappropriate for liquid samples due to its absorbent nature and inability to form a proper seal, which can compromise the sample's integrity.

Therefore, glass containers are the preferred choice for collecting and storing samples for oil and grease analysis, ensuring that the samples remain unaltered and accurate results can be obtained in laboratory testing.