Citrus Industry Magazine CEU 2012 Articles Test Series: Article #2
Protecting your respiratory tract when handling pesticides
By Stephen H. Futch
and Tim Gaver
Posted May 1, 2012
(expires April 30, 2013)
When applying some pesticides, additional protection may be required to protect your respiratory tract. The respiratory tract includes your breathing systems, i.e. nose, mouth, throat and lungs. The respiratory part of your body is much more absorbent to pesticides as compared with your skin or other body parts. If the label directs you to take additional protection of your respiratory tract, you must wear the required protection devices as stated on the label. The label does not prohibit you from wearing additional protection, if you choose, in any pesticide handling operation.
TYPES OF RESPIRATORS
Pesticide labels can vary greatly in requiring specific types of respirators. However, all respirators used when applying pesticides must be approved by the National Institute of Safety and Health (NIOSH) and Mine Safety Health Administration (MSHA).
Failure to select the proper respirator or to wear it correctly could result in poor protection and greater risk of injury during pesticide handling or application. Prior to using the respirator, the user should make sure it fits the face correctly and that it has been cleaned and properly maintained.
Respirators come in two basic types: air-supplying and air-purifying. The type required will be based upon the area being treated and type of pesticide applied.
Air-supplying respirators provide clean and uncontaminated air from an independent source. In general, the source of the air is contained in tanks that are similar to those used when scuba diving. The supplied air is limited in quantity and could be used in 30 to 45 minutes, or even quicker in conditions of elevated temperature or when exertion level is high. These types of respirators are generally used when oxygen levels are low or in enclosed areas during fumigation operations.
Air-purifying respirators, on the other hand, remove the contaminants from the air that you will be breathing. These respirators may not provide adequate protection in all situations, especially when using some fumigants, extreme high concentrations of certain pesticides or in conditions where oxy- gen is low. The air-purifying respirator will remove the contaminants in the air by filtering or removing them from the air you breathe. These respirators come in three basic types: dust/mist filters, cartridge and canister.
Dust/mist filters will filter out or remove dusts, mists and particles from the air you will be breathing. These filters cover the nose and mouth and are held in place by two straps to keep the filter fitting tightly around your face. Filters with only one strap are not approved for use by NIOSH or MSHA due to poor fit around the face. Dust/mist- filtering respirators are identified with an approval number of TC-21C that is issued by NIOSH/MSHA.
Cartridge respirators contain devices that remove either dust/mist and/or vapors from the air you will be breathing. In some cases, the device will have a pre-filter that is designed to remove dusts, mists or other particles before the air passes through the vapor-removing cartridge. The cartridge respirators will have an approval num- ber of TC-23C that is issued by NIOSH/ MSHA.
Cartridge respirators may also consist of a one-piece unit, whereby the cartridges are permanently attached to the face piece. One-piece respirators are discarded after use, whereas two-piece units will contain removable cartridges that are attached to the body of the respirator, allowing them to be removed prior to cleaning the respirator body and then reused. The removable cartridges and pre-filters are replaced when they: 1) become contaminated, 2) you find it difficult to breathe, or 3) you can smell the pesticide when wearing the unit.
The canister respirator will contain both a dust/mist-filtering portion as well as vapor-removing parts. Canister-type devices have also been referred to as gas masks. The filtering capacity of a canister respirator is usually greater than a cartridge respirator, as the size and filtering area are much greater. Canister respirators will have an NIOSH/MSHA approval number of 14G.
When wearing any type of respirator, if it becomes more difficult to breathe, replace the filtering devices as they become clogged with particles that are being removed from the air. The useful life of most devices will vary with use and environmental conditions. Under most conditions, the useful life of the cartridges will not exceed eight hours of continual use. However, if the conditions are dusty, dirty or if the filter becomes soaked with pesticides, the useful life will be shorter and warrant immediate replacement.
All air-purifying respirators draw the contaminated air through filters to remove the contaminants. Most filters will rely on the user’s lung power to pull the air through the filtering devices. For individuals with respira- tory problems like colds, allergies or other issues, it will be difficult to wear these devices as strong lung capacity is needed to draw the air through the filtering devices.
For some pesticides, medical certification is required to ensure that the user is healthy enough to wear the respirator. So, before using a respirator, in- dividuals should have a medical exam- ination to ensure that they are physically fit to wear the respirator. If users ever develop difficulty breathing while wearing the respirator, they should seek medical attention to ensure that a medical condition does not exist that would prohibit them from using the respirator safely and effectively.
Most respirators must fit tightly around the face to work properly and are generally referred to as face-sealing respirators. The tight seal around the face prevents the contaminated air from entering around the edges. Individuals with facial hair or beards will not be able to wear this type of face-sealing respirator as a tight seal will not be formed around the face and surface of the respirator, prohibiting proper air filtering.
Some pesticide labels require fit-testing certification, so each respirator must be fitted to each wearer due to varying facial characteristics. Respira- tors are not interchangeable among users.
To verify that the respirator is properly fitting, users can perform two types of tests: a fit test and a fit check. These simple tests ensure that the user is being properly protected by the specific respirator being worn.
The fit test should be conducted prior to wearing the respirator for the first time and then periodically thereafter. The fit test procedure is a program approved by NIOSH and the Occupational Safety and Health Administration (OSHA) and has specific operation guidelines. The fit test determines if the wearer can detect a substance by irritation or odor, or assay the actual amount/concentration of the test substance that enters the face piece.
The fit check is a check that is usually done on the spot to verify that the respirator is still working correctly. This test should be conducted each time you wear any face-sealing respi- rator. The fit check can be conducted by two methods. The first method in- volves closing off the air inlet of the respirator with your hand, then inhaling so that the face piece collapses slightly, and then holding your breath for 10 seconds. If during this test the face piece remains slightly collapsed for the 10-second period, it is working correctly. However, if the face piece does not remain slightly collapsed for the 10-second period and air movement into the face piece is detected, then it is not working adequately enough to properly protect the user. The second method is to exhale while wearing the device by placing your hand over the exhalation port. If pressure builds up inside the respirator without evidence of leakage, the respirator is working correctly.
Detecting an odor or taste, or experiencing sensory irritation while wearing the respirator would indicate that the device is not fitted or working properly and should be immediately checked to ensure proper filtering of the air entering the respirator.
Loose-fitting respirators are a type of respirator powered by a constant pump in which air is forced through a cartridge or canister into a loose-fitting helmet or hood-head covering. The constant outward movement of air from the respirator prevents contaminants from entering the headpiece. These loose-fitting respirators may provide some advantages when working in situations where heat stress is a major concern, as the movement of air provides some cooling to the face, head and neck.
Proper selection, use and care of pesticide respirators will ensure the safety of the user and provide for optimum protection from airborne contaminants.
Source: Applying Pesticides Correctly, UF IFAS, Gainesville, FL
Stephen H. Futch is an Extension agent at the Citrus Research and Education Center, Lake Alfred; Tim Gaver is an Extension agent at the St. Lucie County Extension Service, Fort Pierce.