Rating 1, 2 or 3 related to microbes in fuel or oil

Microbes in oil, diesel and associated water are measured using the IP613 method (verify the current version with your standards organization). Results are reported as Rating 1, 2 or 3, where Rating 1 is satisfactory and Rating 3 indicates severe biocontamination. The threshold values vary depending on the sample type.

What does the IP613 rating mean for diesel, heating oil or Jet A-1/JET?

For samples of diesel, heating oil or Jet A-1/JET, the following threshold values apply:

• Rating 1 (<4,000 cfu/l): Negligible amounts of bacteria/fungi/yeast have been found in the sample — satisfactory result (negligible biocontamination).
• Rating 2 (4,000–20,000 cfu/l): Moderate amounts of bacteria/fungi/yeast have been found in the sample — moderate biocontamination.
• Rating 3 (>20,000 cfu/l): Large amounts of bacteria/fungi/yeast have been found in the sample — severe biocontamination.

What does the IP613 rating mean for the water phase in diesel, heating oil or Jet A-1/JET?

For water-phase samples from diesel, heating oil or Jet A-1/JET, the following threshold values apply:

• Rating 1 (<1,000 cfu/l): Negligible amounts of bacteria/fungi/yeast have been found in the sample — satisfactory result.
• Rating 2 (1,000–10,000 cfu/l): Moderate amounts of bacteria/fungi/yeast have been found in the sample — moderate biocontamination.
• Rating 3 (>10,000 cfu/l): Large amounts of bacteria/fungi/yeast have been found in the sample — severe biocontamination.

Hydraulic and lubricating oil sample:

What does the IP613 rating mean for hydraulic and lubricating oil?

For samples of hydraulic or lubricating oil, the following threshold values apply:

• Rating 1 (<1,000 cfu/l): Negligible amounts of bacteria/fungi/yeast have been found in the sample — satisfactory result.
• Rating 2 (1,000–10,000 cfu/l): Moderate amounts of bacteria/fungi/yeast have been found in the sample — moderate biocontamination.
• Rating 3 (>10,000 cfu/l): Large amounts of bacteria/fungi/yeast have been found in the sample — severe biocontamination.