Power Tools for Your Program
All three should be in your toolbox before you begin the job of developing and maintaining a respiratory protection program.
DOUBTLESSLY, you have heard that "You must use the proper tools to make the job easier and to end up with the desired result!" Well, this statement applies not only to the traditional hand and power tools you use for home projects and specialized tools you use on the job, but also to the sound respiratory protection program that should be followed in the workplace.
Three primary tools should be used in developing, administering, and maintaining a workplace respiratory protection program. And they pack more power than hammers, pliers, and screwdrivers. The three tools I am referring to are:
* Respirator Selector Guide
* Cartridge Life Expectancy Calculator
* Interactive Training Program
Most respirator manufacturers can provide these tools to you, at no cost, in one or more formats: printed copies, electronically stored on CD or DVD, and/or on the manufacturer's Web site. Regardless of the format, all three of these tools should be in your toolbox before you begin the job of developing and maintaining a respiratory protection program.
Let's discuss each one of these in more detail.
I. Respirator Selector Guide
A Respirator Selector Guide is designed to help you identify the proper respirator solutions to meet individual needs. It encompasses the broadest range of respiratory protective products available, and it can even give you choices that you didn't realize you had.
The choices (depending on your work environment) include everything from self-contained breathing apparatus to half- and quarter-type facemasks. In addition to helping you select the proper respirator, a Respirator Selector Guide helps you to choose the correct filtering element if your exposure situation allows the use of an air-purifying respirator.
Just like the jobs you do around your home, the first step in using the guide is to assess the situation. Know exactly what the environmental conditions are. If you don't know what you're up against, you will not be able to use the tools properly or effectively.
To determine an atmosphere's oxygen content or concentration level of gaseous contaminants, proper air sampling must be done. The results of this sampling will be the basis of how you address the need for respirators and, if so, what level of protection is required. Generally, respirator (and cartridge) selection is based on three factors:
1. The results of your atmospheric monitoring or sampling program;
2. The accepted ACGIH, OSHA, or NIOSH exposure limits for the substance(s) present; and
3. The maximum use concentration (of a substance) for which a respirator can be used.
An additional part of hazard assessment is the determination of whether the contaminant has adequate warning properties. This affects respirator selection, in that chemical cartridge respirators and gas masks should be worn for routine use against only gases and vapors with adequate warning properties, unless the cartridge is equipped with an end-of-service life indicator. After finding out which hazards exist, compare the chemical concentration at your facility (determined by air sampling) with the chemical's exposure limits. Note: Most chemicals listed in a Respirator Selector Guide use the lowest exposure limit published by ACGIH, OSHA, or NIOSH as a baseline to determine the need for respiratory protection. One exception to this rule is when an OSHA substance-specific standard exists with applicable respirator use limitations for protection against the chemical of interest. In this case, the OSHA requirement is specified.
Now it is time to put this tool to work and select a respirator and cartridge. In this selection process, it is important to note that, typically, recommendations in a Respirator Selector Guide are based on appropriate levels of respiratory protection. If you desire, a higher level of protection can be used by selecting a respirator with a higher maximum use concentration or, if applicable, a higher cartridge/filter efficiency. This, of course, would be advisable if the atmosphere in the work area is prone to changes and the contaminant concentration has the potential to become higher.
Let's assume you determined the respirator of choice should be a full-facepiece respirator with a multi-purpose (GME) cartridge. Now you can put that first tool (Respirator Selector Guide) back in the toolbox.
II. Cartridge Life Expectancy Calculator
Now reach into the toolbox and take out the Cartridge Life Expectancy Calculator. This tool is interactive and designed to provide guidance as to how long a specific cartridge(s) should be used before it should be replaced. The determination is called "time of breakthrough," which means the point at which a hazardous chemical will begin to break through the cartridge or filter without being absorbed or collected by the protective barrier.
OSHA requires that respirator cartridges must be replaced at pre-determined intervals, based on work site-specific usage conditions. (Federal Register, p. 1272, col.1, OSHA 1910.134(d)(3)(iii)) OSHA has developed a generic calculator; however, it is important to note the user of the OSHA calculator must plug in the specific carbon characteristics of the cartridge being used. This information is not always readily available from the manufacturer. Also, the OSHA calculator addresses only organic vapors. Some manufacturers provide calculations for a longer list of organics and some inorganic chemicals.
A Cartridge Life Expectancy Calculator is very easy to use. You are asked some key questions, and by simply entering key environmental and usage factors as your answers, the calculator provides you with a suggested maximum service time for the cartridge(s) being used in that specific environment. It is almost as easy as using a hammer or a screwdriver. Although different cartridge calculators may vary, they all need the same information in order to provide you with an answer. This information includes:
1. Chemical hazard (you know this answer from using the first tool discussed);
2. Temperature (this is easily measured);
3. Relative humidity (this is easily measured);
4. Atmospheric pressure (elevation above sea level);
5. What type of respirator you are using (you know this answer from using the first tool);
6. Type of work and average breathing rate (light, moderate, or heavy);
7. Exposure concentration (you know this from your measurements); and
8. Breakthrough concentration preference (this can be used as a safety factor built into the recommendation).
When using a Cartridge Life Expectancy Calculator, you must remember this tool provides a guideline for your final decision on cartridge replacement. Several other factors should also be considered, and the appropriate change-out schedule must be developed by a qualified professional. Other factors might include: Changes in conditions during the work shift, changing climate conditions (seasonal changes), condition of the cartridge or respirator, cartridge storage conditions, accuracy in determining the ambient conditions, and user training experience.
Now that you have made use of the first two tools, you know three important things that will go a long way in helping you tackle the job of protecting the exposed workers from respiratory hazards.
1. You know what the environmental conditions are.
2. You know what your respirator and cartridge choices are.
3. You know how long the cartridges should be used before they need to be replaced with new ones.
III. Interactive Training Program
Using the old but appropriate cliché, last but not least, the third tool that should always be available in your respiratory protection program tool box is an Interactive Training Program for the respirator user.
Some respirator manufacturers offer a program in CD format and/or online via their Web sites. An interactive program offers many more benefits than a simple instruction book or user manual. The program, specific to the individual, is communicated in the primary language of the respirator user. Because it is much more enjoyable to use, it reduces the boredom that is inherent in most technically written instruction books. Most important, the user will remember more through the use of an interactive program.
To ensure effectiveness of this interactive program, the user also should be required to take (and pass) a test about the respirator, including how to wear it and how to maintain it. Because OSHA requires an employee training program covering these topics, you will get the most out of the valuable time spent training the respirator user. Because these interactive programs are available 24/7, potential users can be trained when it's convenient to them, any time, day or night.
In conclusion, if a respirator program is required in your workplace, the job of developing and implementing the program will be much easier if your toolbox is full of the right "power" tools that make your job easier and more effective. Don?t try to miter crown molding with a chain saw!
MSA Cartridge Life Expectancy Results
Final Breakthrough Time Calculation
Here is an example of what the recommendation of a Cartridge Life Expectancy Calculator might be after you have filled in the required information.
When using an Advantage3200 Facepiece with Adv. 200 GME Cartridge under the following conditions:
Chemical Name: Ammonia
Chemical PEL (ppm): 50 OSHA PEL
Temperature: 72 degrees F
Relative Humidity: 75 percent
Pressure: 697 Torr
Breathing Rate: 60 LPM
Use Concentration: 300 ppm
Breakthrough Concentration: 10 percent OSHA PEL
The estimated Breakthrough Time at which cartridges need to be replaced is: 70 minutes
This article originally appeared in the November 2004 issue of Occupational Health & Safety.