Polythene Bags & Plastic Sacks Your Guide To Their Thickness
When talking to Customers about poly bags, were often asked what the terms micron and gauge mean, and how they determine the right polythene bag or plastic sack for the job.
Gauge was the traditional imperial measurement of plastic or polythene thickness, which has now been replaced by micron as the European standard. A micron or micrometre is one millionth of a metre and is represented by the symbol µm. To convert gauge to micron, simply divide by four.
Sometimes we are asked the difference between a polythene bag and a plastic sack. Essentially, they are the same. The term plastic sack is generally used for larger, thicker polythene bags - although we normally refer to them as polybags for short.
Polybags are made using different thicknesses of polythene plastic and it is helpful to know what micron or gauge of polythene has been used, because this will indicate how strong the polythene bag is. The higher the micron or gauge, the thicker the polythene and therefore, the stronger and more expensive the plastic bag.
Below are some of the most popular gauges of polybags and a guide to their general use:
- 100 gauge (25 micron) - light duty polythene bags. Cheap polybags widely used for economic packaging and storage in office, warehouse and industrial applications. These bags provide basic moisture and dirt protection for light goods.
- 120 gauge (30 micron) - general duty polythene bags. Cheap bags used for packaging and storing smooth, light components e.g. clothing, confectionery, leaflets, instruction booklet
- 200 gauge (50 micron) - medium duty poly bags. This bag thickness is the most popular choice for general food packaging, DIY, retail display, bolts, fixings, panels, and kits etc.
- 250 gauge (62.5 micron) - medium duty polythene bags. A good mid range bag and an ideal choice for general packaging, warehouse, retail and industrial applications.
- 400 gauge (100 micron) - stronger, more durable and tear resistant polythene bags. These heavy duty bags are ideal for heavier or more irregular products and are available in larger sizes.
500 gauge (125 micron) - heavy duty, tough and puncture resistant poly bags. Ideal for large or heavier components e.g. machine parts, screws, fixings, fabric protection, packaging goods in transit etc. Again, available as large polythene bags up to 36" x 48" (900mm x 1200mm).
