COVERALLS

Coverall Manufacturing

Coveralls are commonly made from high-density polyethylene (HDPE) formed into a nonwoven fabric that allows heat and sweat to leave the suit while preventing liquids and aerosols from entering it. The sewing of coveralls can be the most difficult part to get right. Seams are closed by putting tape on them to strengthen them and keep them from leaking. However, places where multiple seams join (such as the armpit) can be difficult to seal properly, often making suit construction a trade secret. Lastly, the interfaces on the suit, including the zipper, cuffs, and the edge of the hood or collar, are made liquid-tight to prevent leakage. Depending on the application, cuffs and hood/collar interfaces can be elastic or liquid-tight seals. Zippers can have fabric flaps that cover them or be specially made as liquid-tight zipper assemblies.
Standards

Coverall should be of medium and large size, impermeable to blood and body fluids, single use, avoid culturally unacceptable colours e.g. black, light colours are preferable to better detect possible contamination. Quality standard for fabric as well as seam should meets or exceeds ISO 16603 class 3 exposure pressure, or equivalent. The guideline also says the garment should pass ‘Resistance to penetration by biologically contaminated solid particles (ISO 22612:2005).

Fabrics & Tapes

Although nonwoven is the preferred choice of fabric worldwide due to low cost (as coverall is single use type), there is no mention about same in the guideline. Guideline clearly says that “fabric that cleared/passed/exceeded ‘Synthetic Blood Penetration Resistance Test’ (ISO 16603) class 3 exposure pressure, or equivalent”. Currently all three types of fabrics are being used for making coverall.
Seam sealing tapes are equally important parameters in a coverall.

Sewing & Seam sealing Machinery

The Coveralls should be taped at the seams to prevent fluid/droplets/aerosol entry. Apart from single needle lockstitch machine and four thread overlock machine the manufacturer will require a hot air seam sealing machine and hydrostatic tester

Sterilization and Sanitization

It is important to keep the workplace sanitized as well as the coverall produced should be sterilized before delivery. There are different technology for sterilization; ozone based and UV light based.

Design & Pattern Making

Coverall is defined as a one-piece jumpsuit type loose-fitting protective garment that offer protection against outside contaminants over a large area of the body. It is full sleeve, full leg and fitted with hood. Soft Elastic to be fitted around Front of hood, wrists & ankles. The coverall should have Thumb/finger loops to anchor sleeves in place. There are few variations in design, but overall objective is to minimise the seam in the garment.

Production Planning

The body coverall is having 6-8 parts, having 13 operations and total SAM (sewing + seam sealing) of 11.81. Total seam sealing time is 5.4 minutes per body coverall.