In our last article, we discussed the rising need for personal protection equipment (PPE) in today's mail center and what types of levels are required to ensure continual safety. As the primary barrier between chemical/biological threats and personnel, determining the correct PPE for a given environment is critical.
The right PPE level should be tailored to the needs of the facility and its mission. It must provide the most effective level of protection against wet or dry agents, without compromising overall job performance or comfort.
Considerations for selecting baseline clothing include environmental factors such as heat and humidity, required range of motion, time on station and durability under normal and extreme stresses.
At a minimum, the process should consider design, fit and comfort; chemical/biological resistance; and durability. Because of the extensive variety of options offered by different manufacturers, it is important to evaluate elements such as adaptability to the work environment, ease of donning and doffing, integration with various types of eye and respiratory protection, cost and the ability of any and all parts of the protective ensemble to be decontaminated or disposed of.
The use of various materials necessitates evaluation of the selected PPE to resist chemical infiltration due to absorption-related breakthrough, exposure-related material breakdown or penetration under normal working conditions. Since breakthrough occurs on the molecular level and can occur without visible evidence or the immediate knowledge of the wearer, permeation test results covering a wide range of chemicals should be evaluated to provide a baseline. These tests list the average breakthrough (penetration) time for each garment. When selecting equipment, it's best to compare an average time against the anticipated daily wear time to ensure there is a sufficient safety margin.
Durability and comfort are also important. Because of manufacturing, design, construction and material variations, every article of PPE should be evaluated for its ability to withstand the rigors of daily use in the specific work environment. PPE that is cumbersome to put on or take off, easily rips or tears, fits poorly or causes discomfort should be avoided. Consider potential changes in the PPE's properties under different environmental conditions and, if considering reusable clothing, ensure the material will withstand multiple cleaning and decontamination cycles.
Other safety issues should be considered when implementing a protective clothing policy. In the same way it protects, PPE can also place the wearer at risk for a variety of reasons. It directly impacts the person wearing it by restricting the senses hearing, vision, smell and touch. Additionally, heat and the mental stress of working in a restrictive environment must also be considered when laying out PPE use policy.
Basic Protection and Augmentation Clothing
Equipment designed to protect the skin and eyes from exposure to liquids, powders, solids or gels can be divided into two categories: basic cover clothing that is worn whenever in the work center and augmentation clothing which provides an additional layer of cover for areas not normally requiring it.
As the name implies, basic safety clothing provides the foundation for all types of PPE. When properly employed, it protects the individual's skin from direct exposure to hazardous materials. Basic protection includes underwear, long sleeve shirts, pants (or coveralls), socks and shoes.
Most types of clothing can prevent or delay the effects of exposure to a variety of chemicals and non-airborne biological agents. Because various types of clothing provide different levels of protection, it is best to first identify the minimal level of protection required and then select a standard uniform for the work center.
Standardization in make, design and wear policies, when applied throughout the work center, provides a known starting point in risk mitigation. Uniforms can range from single-use coveralls, specifically designed for hazardous environments and disposed of at the end of each work period, to reusable clothing such as commercial uniforms or hospital scrubs, collected at the end of each shift for laundering and reuse.
As a general rule, and to prevent the possibility of carrying biological or chemical contaminates outside the facility, baseline protective clothing should be restricted to the work center. Additionally, if reusable clothing is being used, it is strongly recommended that the facility assume the responsibility for care, cleaning and replacement.
Disposable gloves, sleeves, hair and shoe covers and lab coats are designed to augment the level of protection provided by baseline clothing and provide an additional barrier against exposure. Such items also include gloves designed to protect against specific chemicals, face shields and various types of eye protection. Normally, these items are constructed of manmade or treated materials designed to maximize protection against known chemical or biological hazards as well as anticipated nonspecific threats.
The level of protection associated with various types and makes of augmentation garments varies depending on the threat. Studies show that the majority of hazardous materials, liquid or solid, remain on the outside of the clothing barrier and the most effective method for reducing exposure is to remove the outer cover as quickly as possible.
Protective gloves, sleeves, lab coats, hair and face shields and shoe covers are designed not only to protect but also to be quickly removed, reducing the time that the user is in direct contact with the hazardous substance.
Bear in mind that no level or combination of protective clothing provides 100% coverage all the time. The user must always be aware that "breakthrough," the point where the protective qualities of the item is overcome by the agent in question, can occur with little or no notice, and that exposure to certain chemicals or fumes can rapidly break down an item's protective capabilities. For this reason, basic clothing should be changed at least once a day, and augmentation covers should be disposed of after every use.
Respiratory Protection
Like PPE clothing and augmentation protection, respiratory protection offers a variety of options depending on the threat and handling environment. This is divided into two categories: filtered (or air purifying) and self-contained atmosphere providing systems.
Air purifying systems provide full or partial face coverage and have filters, cartridges or canisters that remove contaminants from the air. These systems pass the ambient air through the air-purifying element before it reaches the user. Powered air purifying respirators (PAPR) increase protection by providing filtered air under positive pressure to the user via the mask. Such systems ease the stress associated with extended use and allow for higher levels of filtration but tether the user to a personnel fan filter unit and external power source.
Atmosphere providing systems, such as the self-contained breathing apparatus or external air supply systems, provide the user with clean, unexposed air. While such systems provide the highest level of safety, they suffer from major limitations, as they restrict the employee's time on station and movement within the work center.
Commercial dust, non-fitted painter masks and surgical masks do not fit into either of these categories and fail to meet the basic requirements for protection against chemical or fume hazards. While such masks offer minimal protection from biohazards, they are not recommended for use in mail screening environments because of the unpredictable nature of mail-borne pathogens and delivery systems.
The proper selection of respiratory protection depends on the perceived threat and the facility's engineering containment capabilities. Because there is such a vast array of equipment on the market and relevantly high expense associated with these systems, acquiring the advice of a professional experienced in mail center PPE safety program development is highly recommended.
Putting PPE into Action
Are PPE programs worth the time, effort and expense to develop and field? For major facilities servicing high-profile clients, the answer is yes. For smaller facilities, the benefit must clearly be shown to outweigh the cost. This is where consultation with an experienced team of analysts pays off. Advance research and planning will save both time and money and, in the long run, help to ensure the program's effectiveness. Most importantly, it must be clearly understood that there is not a perfect PPE solution. The nature of risk is volatile, meaning it can be mitigated but will never be fully eliminated.
No matter how carefully a threat is evaluated and responded to, there is simply no way to guarantee that exposure will not occur. The most effective weapons in the mail center supervisor's arsenal are advance planning, protective actions, employee education and the proper application and aggressive enforcement of well-defined and up-to-date safety protocols.
Putting together the right combination is key to ensuring continued safety and success.
Don Shanks, Vice President of Engineering, and M. Keith James, Program Manager, SoBran Inc., can be reached at 703-352-1344; dshanks@sobran-inc.com.
