The best method for measuring the preservatives (and all other raw materials) when adding to your products is to weigh them on an accurate scale that weighs down to 0.1 grams. You will find older formulations that use drops, but this is no longer accurate enough.
Use in treatment gels such as Aloe Vera or Hyaluronic Acid serums as well as all types of creams and lotions.
It can tolerate high salt content so is suitable for use in salt body scrubs. Body scrubs may be anhydrous and not be thought to need a preservative, but when they are used with wet hands in the bathroom environment, they should be preserved and Preservative 12 is an excellent choice for this.
Do not use with shampoos and body washes as it will not work. It works well with non-ionic, anionic and cationic materials that are used in hair care products like conditioners.
Hair care products often use a lot of herbs which are more prone to microbial contamination, so remember to increase the percentage of Preservative 12 if using infusions and decoctions to 1.1%.