Manufacturing facilities involved with the production of food, food packaging, pharmaceutical and cannabis products often specify food-grade heat transfer fluids for their equipment. This is a very important subject considering the far-reaching impact of these industries on public health and safety. So, what exactly does ‘food-grade’ mean? In the United States, food-grade heat transfer fluids are certified and registered by the National Sanitation Foundation (NSF). They are classified under the ‘HT-1’ class indicating only approval for incidental food contact. ‘Incidental’ as used here is typically 10ppm (0.001%) or less. This is a very tight tolerance, meaning that if a higher concentration of heat transfer fluids mixes in with the food or pharmaceutical product, the whole batch should be discarded.
Many thermal fluid manufacturers (including Relatherm) also reference compliance with Food & Drug Administration (FDA) requirements as set out in 21CFR Section 178.3570. This regulation essentially established formulation requirements for incident food contact lubricants. This means that food-grade lubricants must be formulated with ingredients listed under the regulation. Based on this, the United States Department of Agriculture (USDA) developed its own incidental contact lubricants category called ‘H1’. This is the precursor to the HT-1 class referred to earlier. The USDA food-grade guidelines also listed other classes – H2 and H3. H2 lubricants can be used where there is absolutely no possibility of food contact. H3 lubricants are edible oils for which direct and prolonged food contact is permitted (e.g soybean oil, cottonseed oils and some white oils)
The USDS maintained a directory of H1, H2 & H3 lubricants until 1998. It transferred that responsibility to NSF with periodic oversight and audit. It is important to note that heat transfer fluids are not lubricants. However, both products are manufactured with common base materials. The historical background provided above is important because it is not uncommon to hear folks use the HT-1 and H1 classifications interchangeably when describing food-grade heat transfer fluids. Ideally, the HT-1 classification is the only NSF category applicable to heat transfer fluids. Relatherm Heat Transfer Fluids has the most expansive line of food-grade thermal fluids. Contact us today to discuss your food, food packaging, pharma or cannabis-oil application.