Asbestos Awareness

WORK CLASSES

Because exposure to airborne asbestos is sometimes difficult to measure reliably, OSHA standards require certain controls for specific asbestos jobs, regardless of measured exposure levels. OSHA groups together work operations that have similar exposure levels and risk into four classes:

Class I work operations cover the removal of "high Risk: ACM and PACM, such as:

• Thermal system insulation (TSI)
• Sprayed-on or troweled-on surfacing material

Class II work operations cover the removal of "lower-risk" ACM and PACM, such as:

• Wallboard
• Roofing materials
• Siding shingles
• Resilient flooring

Class III work operations cover repair and maintenance operations that disturb any previously installed ACM such as:

• Working on boilers, valves or pipes
• Replacing light fixtures or ceiling tiles.

Class IV work operations cover housekeeping and custodial operations that involve minor contact with ACM or PACM such as:

• Clean-up after Class I, II, and II work
• Cleaning up construction waste and debris from the installation of new ACM.
• Stripping and buffing resilient flooring
• Sweeping, dusting or vacuuming asbestos-containing dust from surfaces or carpeting.

PERMISSIBLE EXPOSURE LIMITS

OSHA asbestos standards also contain Permissible Exposure Limits (PELs) that define the maximum allowable employee exposure to airborne asbestos fibers during any work activities.

There are two types of asbestos PELs:

• Time-Weighted Average (TWA) Limit.
• Excursion Limit.

The first PEL - the Time-Weighed Average (TWA) is based on the airborne concentration of asbestos fibers in the work area over a normal eight-hour shift. The TWA may not exceed 1/10 of a fiber per cubic centimeter or air (0.1f/cc), average over eight hours.

An excursion is a short, serve rise in airborne fiber concentrations. It can be caused by a work activity like cutting or grinding ACM with power tools. The Excursion Limit may not exceed one fiber per cubic centimeter of air (1.0 f/cc), averaged over 30 minutes.

Work operations that may cause airborne fiber concentrations to exceed either one of the PELs require respiratory protection for workers, as well as other prescribed work practices and engineering controls.

WORK PRACTICES AND ENGINEERING CONTROLS

Each asbestos work class has a specific set of work practices and engineering controls required by the OSHA standard. If an asbestos work operation does not clearly belong in a single class, you must comply with approved practices and controls for the more restrictive class.

Before you are assigned to duties that may expose you to hazardous concentrations of airborne asbestos fibers, you will be trained in the specific practices and controls for that particular job.

However, there are three basic practices and controls that are required at all times, on any class of asbestos job:

• Wet methods
• High-Efficiency Particulate Air (HEPA) filtered vacuums
• Prompt cleanup of all waste and debris containing ACM or PACM.

PROTECTIVE CLOTHING AND EQUIPMENT

OSHA standards also prescribe other safety measures, such as:

• Protective clothing
• Respiratory protection

Protective clothing

On some asbestos jobs, you may be required to wear special clothing to protect your skin from large accumulations of asbestos dust or debris. Protective clothing may include coveralls, head coverings, gloves and foot coverings.

Respiratory protection

According to OSHA standards, approved respirators are required any time employees will be exposed above the TWA or the Excursion Limit, and in all emergency situations involving asbestos.

Respirators are always required in regulated areas where Class I work is performed.

REGULATED AREAS

Regulated areas are another OSHA control measure to protect employees from exposure to airborne asbestos. I your building contains an asbestos regulated area, it's important for you to know how to reduce your risk.

Establishment

Employers establish regulated areas at all locations where Class I, II and III asbestos work is performed, or where fiber concentrations may exceed either of the PELs.

Demarcation

Regulated areas must be closed off to prevent airborne asbestos from migrating to nearby areas, and marked with warning signs to prevent unauthorized entry.

Access

Entry to regulated areas is strictly limited. Never go into a regulated areas unless you are authorized by your employer, and your work requires you to enter.

Respirators

If you must enter a regulated area where respiratory protection is required, wear a respirator approved for the airborne concentration of asbestos in that area.

Prohibited activities

To avoid the possibility of asbestos fibers entering your body through your mouth, never eat, drink, chew tobacco or gum, or apply cosmetics in a regulated area.

ASSESSMENT AND MONITORING

All asbestos work performed within a regulate area must be supervised by a trained "competent person" who can identify asbestos hazards in the workplace and take prompt corrective measures to eliminate them.

One of the duties of the competent person is to conduct employee exposure assessment and monitoring in areas where workers may be exposed to asbestos fibers.

Initial Exposure Assessment. Before anyone performs work covered by the asbestos standards, the competent person conducts an assessment to:

• Predict whether exposure levels during the planned asbestos work may exceed the PELs
• Determine what work practice and controls will be required.

Periodic Monitoring - As long as the job goes on, the competent person conducts periodic atmospheric monitoring of the work site to determine airborne asbestos concentrations. The fiber concentrations of personal breathing zone air samples are measured periodically in regulated areas, to make sure employees are not exposed above either the TWA or the Excursion Limit.

MEDICAL SURVEILLANCE

If you work directly with asbestos, another preventive measure to protect you from its hazards is medical surveillance.

Medical surveillance is used to:

• Monitor your physical condition
• Determine your actual exposure to asbestos.

Your employer will provide medical exams periodically at no cost to you. To protect your privacy, these exams are strictly limited to asbestos-related conditions.

INFORMATION AND TRAINING

Employee information and training programs reduce your risk of exposure and show you how to work safely in areas that may contain asbestos.

Information - The new OSHA standards require building owners to maintain permanent records on ACM in their buildings. Employers must provide this information to all workers exposed to asbestos hazards. For example, if you perform housekeeping activities in areas that contain ACM or PACM, your employer will inform you of the presence and location of these materials.

Training - OSHA standards require training for employees who are actively exposed to asbestos by performing Class I through IV work, or who install new asbestos products. Regardless of job title - such as janitor, custodian or maintenance worker - the level of training required is determined by the specific nature of the operations performed by a given worker.

To simplify and standardize Federal requirements, training provisions in the new OSHA standards are identical to existing programs developed by the Environmental Protection Agency (EPA) under the Asbestos Hazard Emergency Response Act ( AHERA).

EMERGENCY RESPONSE

Asbestos fiber release episodes result when asbestos-containing building materials fall or are dislodged from pipes, ceilings or other locations where they are installed.

Federal standards cover two types of fiber release episodes:

• A minor fiber release episode involves three square linear feet of ACM or less.
• A major fiber release episode involves more than three square feet or three linear feet of ACM.

Do not attempt any emergency response to a fiber release episode unless:

• You have been assigned such duties by your employer
• You are fully trained and equipped for the job.

The proper response to a fiber release episode is to take appropriate actions to protect human health and the environment. For a major fiber release episode, specific response actions must be designed by an accredited person.

DOING YOUR PART

Your employer is responsible for notifying you if you are at risk from exposure to asbestos, and for taking certain steps to protect you. However, you have a responsibility to work with your employer to ensure compliance with OSHA and EPA standards.

Now it's up to you. Work safely by staying smart about asbestos.

NESHAP:

The NESHAP is intended to minimize the release of asbestos fibers during activities involving the handling of ACM, specifies work practices to be followed during renovations of buildings which contain threshold amounts of friable ACM, and also specifies work practices during demolition of a facility. Sources covered by the NESHAP are roadways containing ACM, demolitions of all facilities, renovation of facilities that contain friable ACM, and active waste disposal sites (landfills) receiving friable ACM.

A facility is defined as any institution, commercial, public industrial, or residential structure, installation, or building (including any structure, installation, or building containing condos or individual dwelling units operated as a residential cooperative, but excluding residential buildings having four or fewer dwelling units); any ship; and any active or inactive waste disposal site.

Threshold amounts of Regulated Asbestos Containing Materials (RACM) under the NESHAP are:

• At least 260 linear feet on pipes, or;
• At least 160 square feet on other facility components, or;
• At least 35 cubic feet off facility components where the length or area could not be measured previously.

RACM is defined as friable asbestos material, Category I nonfriable ACM that has become friable, Category I nonfriable ACM that will be or has been subjected to sanding, grinding, cutting, or abrading, or Category II nonfriable ACM that has a high probability of becoming friable.

 

Category I (CAT I) nonfriable ACM is asbestos containing gaskets, packings, resilient floor covering, resilient floor covering mastic, and asphalt roofing products containing more than one percent asbestos.

 

Category II (CAT II) nonfriable ACM includes all other nonfriable ACM, for example, asbestos-cement (a/c) shingles, a/c tiles, and transite boards or panels containing more than one percent asbestos.

 

Note: Category I ACM and Category II ACM are distinguished from each other by their potential to release fibers when damaged. Category II ACM is more likely to become friable when damaged than is Category I ACM.

For demolitions, even if no asbestos is present, and renovations with threshold amounts of RACM, the NESHAP requires from the property owner or demolition/renovation operator to submit, to the NESHAP administrator (Pima County Department of Environmental Quality), a notification of intent to demolish/renovate.

For demolitions with threshold amounts of RACM, the NESHAP mandates removal of all RACM prior to demolition. During the removal (renovation) of the RACM the operator must comply with NESHAP emission controls.

The NESHAP also specifies requirements for the disposal of RACM. RACM being disposed must be adequately wetted, packaged in leak tight wrapping or bags, labeled appropriately according to the regulations, and manifested for disposal.

ILLEGAL DUMPING

Waste materials that are illegally dumped, such as in the desert, are first and foremost considered Solid Waste. Solid waste can be hazardous, depending on the nature of the materials. Asbestos waste, illegally dumped, therefore is a solid waste regardless of the amounts or the condition it is found in.

In Arizona, asbestos waste, if it is friable, is considered a "Special Waste" requiring special disposal procedures. Special waste upon disposal, conforming with the NESHAP threshold amounts, must be reported to the Arizona Department of Environmental Quality (ADEQ), who issues a special identification number to be used for transportation of the materials and disposal at landfills approved to receive these wastes.

Therefore, asbestos waste found illegally dumped poses a health hazard as well as an environmental hazard. Although any asbestos waste can be found illegally dumped, the most common materials are asphaltic built-up roofing, asbestos cement (A/C) shingles, vinyl asbestos floor tile (VAT), and A/C pipe (transite). Caution measures should be employed when suspected ACM is found illegally dumped.

PROCEDURES FOR ACCEPTANCE OF NON-REGULATED ASBESTOS AT THE TANGERINE ROAD LANDFILL.

• Non-regulated asbestos will be accepted only at the Tangerine Road Landfill Monday through Friday between the hours of 7:40 a.m. and 3:00 p.m. (except holidays) If loads require special handing, the acceptance times may vary.
• A Pima County Non-regulated Asbestos Disposal Manifest must accompany each load.
• The driver must inform the cashier that the load contains non-regulated asbestos.
• The driver shall follow all instructions of the landfill personnel.
• The unloading operation shall be supervised by landfill personnel.
• For transite pipe, seal broken ends with paint. The sealant must be noticeable and adhere to the surface of the pipe. (Powdery survey paint does not usually provide an adequate seal.) All other broken areas along the pipe must also be sealed. A container with a "swing-gate" is recommended for dumping multiple lengths of pipe. Please do not overload containers in a manner that will crush pipe or will cause the pipe to get caught by the hauling container.
• Please schedule large loads of transite or other bulky non-regulated asbestos containing materials by contacting Pima County Solid Waste at 740-6650.
• If mixing non-regulated with regulated material, the entire load will be considered regulated. In this case, all material should be bagged and labeled in accordance with NESHAP Requirements. Pima County Solid Waste Management does not accept regulated asbestos for disposal at any other facility.
• The load may be refused if the above listed criteria are not met.

LIST OF MATERIALS LIKELY TO CONTAIN ASBESTOS

Material Types:
M = Miscellaneous Material
S = Surfacing Material
TSI = Thermal System Insulation

ANALYTICAL METHODS

Phase Contrast Microscopy (PCM)

Phase Contrast Microscopy (PCM) is a technique using a light microscope equipped to provide enhanced contrast between the fibers and the background. Samples for PCM are collected on amixed cellulose ester membrane filter with a 0.8 micrometer pore size. Filters are then cleared with an acetone vapor so that trapped particulate material can ve viewed through the microscope at a magnification of approximately 400X. PCM is inexpensive (+- $25) and, when necessary can be performed on the job site in a few hours.

Phase Contrast Microscopy is frequently referred to as the light microscope method, the filter membrane method, or the NIOSH 582 method. PCM is the analytical method specified in the Occupational Safety and Health Administration (OSHA) Asbestos Standard (29 CFR 1910.1001, amended, and 29 CFR 1926.1101). PCM is used to monitor asbestos exposure to workers in asbestos work areas. This method does not distinguish between fiber types and only counts those fibers 5 microns or longer, and at least 3 times as long as they are wide (3:1 aspect ratio). Because of these limitations, fiber counts by PCM typically provide only an index of the total concentration of airborne asbestos in the environment monitored. As the proportion of the airborne fibers which are less than 0.25 micrometers in diameter increases (i.e., non-industrial settings such as asbestos abatement projects). PCM becomes a less reliable analytical tool.

Transmission Electron Microscopy (TEM)

Transmission Electron Microscopy is a technique which focuses an electron beam onto a thin sample. As the beam transmits through certain areas of the sample, an image resulting from varying density of the sample is projected onto a fluorescent screen. Air samples are collected on either MCE or polycarbonate filters for TEM analysis. The cost is about $100 - $300 per sample. The analyses can be performed within several days, but due to the limited number of experienced laboratories, it may take several weeks or more to obtain results. Quick turn-around results may be purchased, but are more expensive.

Transmission Electron Microscopy is currently considered the best available analytical method for identifying asbestos fibers collected on air samples. TEM can identify the smallest fibers and is specific for asbestos. TEM equipped with selected area electron diffraction (SAED) capabilities can also provide information on the crystal structure o an individual particle. EPA, in its AHERA regulations, requires TEM analysis of most final clearance air samples.

Polarized Light Microscopy (PLM)

Polarized Light Microscopy is the most commonly accepted method for analyzing bulk materials for the presence of asbestos. This method is inexpensive (+- $35) per sample) and can be performed in a few hours. PLM is based on optical mineralogy using a light microscope equipped with polarizing filters. Identification of asbestos fiber bundles is based on the determination of optical properties displayed when the sample is treated with various dispersion staining liquids (refraction index liquids). In addition, identification can be substantiated by morphology of the fiber and the effect of polarized light on the fiber.

The reliable limit of detection for this method is about one percent asbestos. Samples of extremely fine dusts, such as brake dust, should be analyzed by electron microscopy which can detect the smaller fibers. PLM is required by EPA regulations for analysis of bulk samples.