Milk can get contaminated in these ways:
Germs from an animal’s skin can get in milk Germs in the environment (including the barn and milking equipment) can get in milk The dairy animal’s udder can be infected (mastitis) The dairy animal can have a disease (for example, bovine tuberculosis) Insects, rodents, and other small animals can get in milk Conditions in the milk processing plant can be unsanitary Cross-contamination from dairy workers can happen—for example, through contact with dirty clothing or boots
A sterile field is considered contaminated if you turn your back to the sterile field because the sterile items are considered out of vision.
If a sterile field becomes "contaminated" with a sterile solution, the field remains sterile.
Milking machines revolutionized dairy farming practices by automating the milking process, increasing efficiency, and reducing the manual labor required. Before milking machines, farmers had to milk cows by hand, which was time-consuming and physically demanding. The introduction of milking machines allowed for faster, more consistent milking, leading to increased productivity on dairy farms.
Using sterile gloves and making sure it does not touch any non-sterile/contaminated objects
You throw it out and start over, regardless the cost.
the whole thing is considered contaminated
No, unless it was extremely poorly produced, in a contaminated, non-sterile facility.
Urine is typically sterile when it exits the body, but it can become contaminated with bacteria from the skin or external environment within a few minutes to an hour.
If a sterile field becomes wet with a nonsterile solution, the best course of action is to consider the field contaminated and change it. Start over with a new sterile field to maintain a sterile environment for the procedure. It is crucial to prioritize patient safety and maintain a sterile field to prevent infections.
Anything you breathe in, dust, germs particulates, all pass through the lungs, so no; the air inside would not be sterile. It'd be contaminated by anything you've taken in.
If it is left open on the bench it can be contaminated by bacteria in tyhe air, e.g. micrococci. If the loop was not flamed adequately before innoculation this can also cause contamination. and also if the medium used was not sterile in the first place the plate will be contaminated.
A sterile bottle will typically stay sterile as long as it remains unopened and the seal is intact. Once opened or exposed to the environment, the bottle could become contaminated and lose its sterility. It is important to follow proper sterilization and storage protocols for maintaining sterility.