The Science and Safety Behind the White Suits

An essential element of any safety program, a hazard risk assessment should be completed before starting any work task.  The associated hazards with your planned activities should be identified and evaluated. 

How exposed is the worker?  How much of the hazard will the worker be exposed to?  How concentrated or intense is the hazard?  How long will the exposure last?  How frequently will the exposure occur?

Once these questions have been considered, exposure controls should be determined and implemented.  The Occupational Safety and Health Administration (OSHA) identifies a hierarchy of exposure control, with PPE serving as the last line of defense.

1. Substitution – Can the hazard be reduced or eliminated?
2. Engineering – Are there technical solutions to make the job safer?
3. Work Practices – Are the proper tools and procedures in place?
4. PPE – Does the worker need to wear something for personal protection?

When evaluating garments in relation to your specific risks and hazards, three important elements to consider are fabric, seam, and design.

Key fabric selection criteria are protection, durability, and comfort.

• Protection – Will potentially hazardous material penetrate through the garment? Does it comply with industry and/or government requirements?
• Durability – Will it maintain its protection throughout the task? Will change-outs be required during the task?
• Comfort – Will the garment contribute to heat stress? Will wearing the garment lower worker productivity?

Seams can help provide garment strength, durability, and hazard protection, however, seams can potentially be a weak barrier location on the garment.  There are five main types of seam construction:

• Serged (Sewn) – A seam is produced when threads are interlocked around the edges of two pieces of fabric
• Bound – An outer binding is added to a tightly sewn seam to increase seam strength and improve seam barrier
• Welded – A seam is created by fusing two pieces of material ultrasonically or thermally
• Taped – A strip of compatible material over a sewn seam increases strength and improves barrier protection against heavy liquid splash
• Double Taped – A strip of compatible material covers both the inside and outside surface of a sewn seam

Garment design features are linked to end user needs.  The hazard risk assessment will help determine the appropriate PPE accessories and styles that should be used (e.g. coveralls, lab coats, hoods, sleeves, shoe covers).