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Program Policy Manual

VOLUME V - COAL MINES

INTERPRETATION, APPLICATION, AND GUIDELINES
ON ENFORCEMENT OF 30 CFR

PART 70 .... MANDATORY HEALTH STANDARDS -
UNDERGROUND COAL MINES

Subpart A .... General

This Part 70 is not applicable to shaft and slope sinking operations until the coal bed is reached and actual mining begins in the coal bed. Until reached, the regulations set forth in Part 71 are applicable.

Subpart B .... Dust Standards

70.100 Respirable Dust Standards
(b) The 1.0 milligram standard for intake airways is applicable within 200 feet outby the working faces of each section. The 2.0 milligram standard identified in paragraph (a) of this section is applicable to the remaining parts of the intake airways.

70.101 Respirable Dust Standard When Quartz is Present
The lowering of the respirable dust standard from 2.0 mg/m3 due to excessive levels of quartz will normally be based on the combined average of operator and MSHA samples. However, if operators elect not to participate in the dust standard setting process, or operator sample(s) are either voided or not received in time, the standard will be based on the MSHA sample only or on the sample (either MSHA's or operator's) with the highest quartz percentage, in accordance with the technical procedures of the revised quartz program implemented December 1, 1985. The respirable dust samples will be processed against a reduced dust standard as follows:

  1. If an entity is in bimonthly processing at the time a new standard is set, and at least one sample is received that was taken prior to or on the date that the operator was notified of the change (the date of the data mailer), all samples taken for that bimonthly cycle will be applied against the prior standard. If all samples are taken after the date of the data mailer, the new standard will apply.

  2. When an operator has been requested to submit five additional samples and a new standard is established, if at least one sample is received that was taken prior to or on the date of the data mailer informing the operator of the new standard, all five samples will be applied against the prior standard. If all samples are taken after the date of the data mailer, the new standard will apply.

  3. If the samples submitted for a request for five additional samples results in compliance and also split cycle processing, the applicable standard will be based on the same criteria as regular bimonthly samples. If at least one sample that will determine compliance for the next cycle is taken prior to or on the new standard effective date, the prior standard will apply. Otherwise, the new standard will apply.

  4. If an entity is in citation processing when a new standard is set, the applicable standard will be based on the date the fifth valid sample of any set is taken. If the sample taken date is after the standard is set, the new standard will apply. Otherwise, the prior standard will apply.

  5. If samples submitted to abate a citation result in split cycle processing, the standard applied to determine compliance for the citation will also apply to determine compliance for the next bimonthly cycle.
Subpart C .... Sampling Procedures

70.201 Sampling; General Requirements
(b) In cases where the designated occupation of a MMU works longer than 480 minutes or the production shift for a DA is longer than 480 minutes, arrangements shall be made to remove the sampling device from the miner at the expiration of this time period.

(c) The purpose of this requirement is to enable MSHA to observe the sampling procedures of a particular operator. If MSHA requires a mine operator to submit the date on which respirable dust samples are to be collected and the operator fails to comply with this request, a citation for violating this section shall be issued. However, if an operator reports that samples are to be collected on a particular date but does not do so due to circumstances beyond the operator's control, a citation is not issued.

(d) If the respirable dust standard is changed when samples are being submitted to abate a citation, these respirable dust samples will be processed in accordance with the policy described under 70.101.

When the operator does not take corrective action to reduce the concentration of dust before taking samples, and the sampling results show continuing noncompliance, the inspector shall not extend the time for abatement of the violation and shall issue the appropriate order.

70.204 Approved Sampling Device; Maintenance and Calibration
(d) "Immediately before each sampling shift" is interpreted to mean not more than 3 hours before the shift in which the sampling device will be used to collect a sample for the Part 70requirements.

70.205 Approved Sampling Devices; Operations; Airflow rate
(c) In determining when the proper flow rate has not been maintained and when the certified person is required to note this on the dust data card, the following criteria shall be used:

If the roto meter float (flow rate indicator) has dropped below 0.5 float diameters for the MSA Model G sampler, the certified person is required to note on the dust data card that the proper flow was not maintained.

70.207 Bimonthly Sampling; Mechanized Mining Units
(a) Although this provision does not set forth exactly when during the bimonthly period the required sampling should be conducted, it is to the operator's advantage to conduct sampling as early as possible during the first month of each bimonthly period because it would provide an opportunity to collect replacement samples if any sample is voided.

This section establishes the requirement for the operator to submit the required valid respirable dust samples during the established bimonthly periods. This sampling requirement is an important aspect of the monitoring program designed to ensure miners are provided a working environment that meets the applicable respirable dust standard. An operator with a reasonable opportunity to have collected and submitted the required valid samples during the bimonthly period who fails to do so may be cited for noncompliance. While District Managers will consider mine-specific circumstances, as a general matter MSHA would expect that operators whose identified sampling entity was in producing status at least 50% of the bimonthly period would have had sufficient opportunity to obtain and submit the required valid respirable dust samples.

If the respirable dust standard is changed during a bimonthly period, dust samples required by this section will be processed in accordance with the policy described under 70.101.

(b) This section establishes when an operator is required to begin bimonthly sampling on an MMU after the dust standard has been changed because of the presence of excessive levels of quartz dust. It applies only to the bimonthly period immediately following notification by MSHA and not to the subsequent bimonthly periods.

(e) If the operator's mining procedures result in the changing of miners from one occupation to another during a production shift, the sampling device must remain on or at the designated occupation (DO). For example, if an operator alternates the duties of the continuous operator on a one-half shift basis between the continuous miner operator and helper, the dust sampler shall be worn for one-half of a shift by the continuous miner operator and the other one-half of a shift by the helper, while each is operating the continuous mining machine, or the sampler shall remain on the machine as required by this section.

A change in the designated occupation of an MMU will be considered after the results of samples collected by MSHA indicate that a work position other than those identified in this section should be designated for bimonthly sampling. When the results of a sampling inspection demonstrate appreciably higher respirable dust levels at a nondesignated occupation within an MMU, consideration should be given to changing the designated occupation.

(f)(1) The MMU identification number will remain the same when individual pieces of equipment within that unit are replaced. The only time the MMU identification number sequence at a mine will change is when an existing unit of equipment is permanently removed from the mine or a new (or different type) unit of equipment is placed in a mine. The only time a reduced respirable dust standard associated with an MMU will be eliminated/changed is either 1) based on the MMU being permanently removed from the mine and no other MMU being placed in producing status to maintain the number of active MMUs or 2) based on the quartz results of MSHA samples indicating quartz levels that are 5% or less on the existing or replacement MMU.

For example, an operator has an auger-type continuous mining machine on MMU 003-0, which is on a reduced respirable dust standard of 1.5 mg/m3. The operator decides to replace the auger-type mining machine with a ripper-type continuous mining machine. Since the operator is replacing the auger-type machine with a ripper-type machine, MSHA changes the MMU number. However, since the designated occupation and dust control parameters will be changed, the operator will be required to submit a revised dust control plan and the reduced standard on MMU 003-0 would remain at 1.5 mg/m3 on the new MMU until the operator can show a substantial reduction in the quartz levels on the MMU. Another example would be an operator changing a ripper type continuous mining machine with a different ripper-type mining machine. If the dust control parameters associated with both machines are the same, MSHA will not change the MMU number and the operator will not be required to submit a revised plan. However, a written notification of this change should be submitted by the operator and filed with the appropriate plan.

70.208 Bimonthly Sampling; Designated Areas
(a) Bimonthly sampling begins after each designated area is identified in the coal mine operator's ventilation plan (see 75.371(t)) approved by the district manager and established in the computer database. Operator bimonthly dust samples from an entity not established in the database will be rejected by the computer.

Although this provision does not set forth exactly when during the bimonthly period the required sampling should be conducted, it is to the operator's advantage to conduct sampling as early as possible during the first month of each bimonthly period because it would provide an opportunity to collect replacement samples if any sample is voided.

This section establishes the requirement for the operator to submit the required valid respirable dust samples during the established bimonthly periods. This sampling requirement is an important aspect of the monitoring program designed to ensure miners are provided a working environment that meets the applicable respirable dust standard. An operator with a reasonable opportunity to have collected and submitted the required valid samples during the bimonthly period who fails to do so may be cited for noncompliance. While District Managers will consider mine-specific circumstances, as a general matter MSHA would expect that operators whose DA was in producing status at least 50% of the bimonthly period would have had sufficient opportunity to obtain and submit the required valid respirable dust samples.

If the respirable dust standard is changed during a bimonthly period, dust samples required by this section will be processed in accordance with the policy described under 70.101.

(b) See 70.207(b) for explanation of the phrase "shall begin on the first production shift..." as it applies to this section.

Additionally, as with designated sampling entities, whenever a non designated entity (NDE) on a reduced dust standard changes to a non producing status and then, at a later date, becomes producing again, the reduced standard still applies to that NDE.

(c) This provision requires the operator to collect additional samples within 15 calendar days of receipt of the MSHA request.Sampling must begin on the first day following receipt of notification on which there is a production shift. The operator,however, is not required to collect these samples on consecutive calendar days. If compliance with the 15 calendar day sampling requirement has not been demonstrated or cannot be determined,the inspector would issue a citation for failure-to-sample under this section. However, if the operator is able to show evidence that the additional valid samples were collected within the required time period, the inspector should vacate the citation.

An advisory notice on noncompliance for failure to submit additional samples will also be sent to the district and subdistrict offices when an operator collects the required 5additional samples within 15 calendar days of receipt of the MSHA request, but one or more of the samples is voided. When this occurs, the operator will be notified through the computer system that the voided sample(s) must be replaced. The replacement samples must be taken by the operator as soon as reasonably possible after notification. If an operator fails to replace the voided sample(s) promptly, a citation for failure to take 5 valid samples would be issued. If a replacement sample is voided, MSHA personnel should issue a citation for failure to take 5 valid samples in accordance with Section 70.208(c).

The procedure described above, which allows an operator an opportunity to replace one or more voided samples from a set of 5 additional samples, is discretionary with the district manager and is to be used only once or twice a year at a mine.Operators shall not be allowed additional time to replace voidedbimonthly samples.

If the respirable dust standard is changed prior to the time an operator has been requested to submit five additional samples or while collecting such samples, these samples will be processed in accordance with the procedures described under 70.101.

(e) The intent of this provision is to have samples collected at strategic locations in the mine where miners normally work or travel to demonstrate that the respirable dust concentration complies with the applicable standard.

The following guidelines are to be applied by the District Manager for selecting and approving designated areas (DAs), which shall be shown in detail in the ventilation system and methane and dust control plan (see 75.316-1(b)(2)):

  1. Track Haulage:

    1. Sample where miners are exposed to dust generated by rotary dumps.

    2. Sample on haulage locomotives where it has been established that quartz content of the locomotive operator's environment has exceeded 5 percent, or when prior sampling of the locomotive operator has indicated concentrations in excess of 1.0 mg/m3. The DA should be the same route of travel and type of locomotive where sampling indicated the problem.

  2. Belt Haulage:

    1. Sample belt to rail transfer points.

    2. Sample where the air in the belt entry is regulated into the return airway. This applies only to areas where the major volume of air is being regulated into the return airway. It does not apply where small amounts of air are being bled off to control the air velocity along the belt.

    3. Sample along the belt lines so that each measurement represents up to, but not more than, four dust generation sources (transfer points).

    4. Sample each side upwind (opposite the direction of airflow) of the location where different splits of air join into a common return airway. This requires two designated area sampling locations.

  3. Trackless Haulage:

    1. Sample dump points outby the working section where it has been established that respirable dust concentrations exceed 1.0 mg/m3.

    2. Sample on coal haulage or supply vehicles where it has been established that the quartz content of the vehicle operator's environment has exceeded 5 percent or where prior sampling of the vehicle operator has indicated concentrations in excess of 1.0 mg/m3. The designated area should be the same route of travel and type of vehicle where sampling indicated the problem.

  4. All Other Dust Generation Sources: Shops, section dumping points and other areas where miners may be exposed to respirable dust concentrations greater than 1.0 mg/m3 as indicated by MSHA or prior operator samples, are to be handled on an individual basis. If dust concentrations are greater than 1.0 mg/m3, MSHA should require mine operators to add these areas to the plan as designated area sampling locations.

  5. Selection of Sampling Points Within DA: The placement of the respirable dust sampling instrument within a designated area is critical to obtaining a representative measurement of respirable dust concentrations at the location. Dust sampling instruments should be positioned within designated areas so that the measurement is indicative of the highest dust exposure to personnel who are required to work or travel in that area. The position of all dust sampling instruments shall be described in the dust control plan as required by 75.316-1(b)(2). Guidelines for selection of this position are:

    1. Generally, within 10 to 20 feet downwind (with direction of airflow) of the dust generating source.

    2. In belt entries, approximately 50 feet upwind (opposite direction of airflow) from the center of each intersection where air is directed into a return airway.

    3. At normal breathing level, but not less than 1 foot from the roof or rib.

    4. More than 2 feet from any obstruction and placed in a manner where it will not be directly behind an obstruction which would affect the airflow around a sampling device.

    5. Within 36 inches of the operator's control station or normal work position, such as locomotive operators, trackless haulage equipment operators, etc.

  6. Adding Designated Area Sampling Locations: The district manager may require or accept designated area sampling locations based on:

    1. These guidelines.

    2. Personnel working at or near a dust-generating source.

    3. Respirable dust sample(s) collected in the proposed area during the last year which has exceeded 1.0 mg/m3 or a reduced standard of 1.0 mg/m3 or less.

    4. The coal mine operator submitting additional designated area sampling locations for approval at any time.

  7. Removing Designated Areas From Sampling Status: If each of the valid respirable dust samples collected from a DA by the operator during a 1-year period indicates a respirable dust concentration at or below 1.0 mg/m3 when on a 2.0 mg/m3 standard or at or below the applicable standard when on a reduced standard of 1.0 mg/m3 or less, the district manager may remove the DA from sampling status provided:

    1. At least one valid sample has been collected from the same DA within the same 1-year period by MSHA, and

    2. Each respirable dust sample taken by MSHA indicates a respirable dust concentration at or below 1.0 mg/m3 when on a 2.0 mg/m3 standard or at or below the applicable standard when on a 1.0 mg/m3 standard or less, and

    3. A minimum of five valid respirable dust samples have been taken in the same DA. These five valid samples consist of a combination of MSHA and operator samples.
This only allows the operator to stop sampling the DA. Since the previous samples only indicated that the dust control measures were adequate, dust control parameters stipulated in the approved dust control plan shall not be changed unless the changes have been evaluated based on MSHA samples.

Between the 6-month reviews of dust control plans, it is not unusual for the physical layout of a mine to change, thus requiring some DAs to be placed in a non producing or abandoned status. When the physical layout of a mine changes, new DAs for that mine are not established until the next 6-month review period. However, when status changes occur between 6-monthreviews, (i.e., from non producing to producing) normal bimonthly sampling will commence during the bimonthly cycle in which the status change occurs.

In addition to uniquely identifying the DA to be sampled, the four-digit identification number or entity number identifies the type of DA. The following is a list of the DA types with corresponding codes assigned by MSHA which are required to be entered on the respirable dust data card accompanying each sample:


Numeric Designation
DA Type Description
__________________ __________________________
100-0 through 199-9 Track haulage
200-0 through 299-9 Belt area
300-0 through 399-9 Trackless haulage
400-0 through 499-9 Shops
500-0 through 599-9 Section dumping points
600-0 through 699-9 Rotary dumps and crushers
700-0 through 799-9 Miscellaneous
800-0 through 899-9 Intake Airways
900-0 through 999-9 Roof Bolters

70.209 Respirable Dust Samples; Transmission by Operator
(b) Any time a citation is issued in accordance with this provision, all pertinent information shall be submitted to the Senior Special Investigator in the district. Based on the facts,this investigator will determine if further investigation and enforcement actions are warranted.

(c) When filling out each dust data card, it is important that the correct sample type be entered in the box provided. The environment sampled should be numbered as follows:

U.G. Designated Occupation .........................................................1
U.G. Non designated Occupation ..................................................2
U.G. Designated Area ...................................................................3
Surface Designated Work Position .................................................4
Part 90 ..........................................................................................5
U.G. Non face Occupations ...........................................................6
U.G. Intake Air ..............................................................................7
Surface Non designated Work Position ...........................................8

Code numbers 1 through 5 will be used by coal operators and MSHA inspectors, while numbers 6 through 8 will be used exclusively by MSHA inspectors only. Code number 2 is to be used by MSHA inspectors when an underground non designated occupation is sampled. The only time an operator would use code 2 would be after an excessive dust citation has been issued on a non designated occupation and, as a result, the operator is sampling the environment to get back in compliance.

The four blocks in item 10 of the dust data card are for the number assigned by MSHA to identify the Mechanized Mining Unit(MMU), Designated Area (DA), Designated Work Position (DWP) or Part 90 miner. Part 90 miners working underground should be coded 850-0 if not working on an MMU. If the Part 90 miner is working on an MMU, the MMU identification number shall be used.

Part 90 miners working on the surface shall be coded 950-0. The entity being sampled must be properly identified before sampling can be credited.

(d) Although cassettes may not be of the approved type, the sampling unit must be approved as intrinsically safe if used inby the last open crosscut or in return air.

70.210 Respirable Dust Samples; Report to Operator
(b) This posting requirement applies to the monthly report of samples and does not include the data mailers that are received by the operator on a daily basis. However, Part 90 sampling data is not to be posted.

70.220 Status Change Reports
(a) This section shall be cited when it is determined that the operator has failed to collect samples for Part 70 and did not notify the District Manager, in writing, within 3 days after a status change affecting sampling occurred. A status change submitted within 3 working days after the end of a bimonthly period or more than 3 working days after the status change occurred does not meet this section's requirement.

Subpart D .... Respiratory Equipment

70.305 Respiratory Equipment; Gas, Dusts, Fumes, or Mists
As used in Section 204 of the Act, the term "short periods" is interpreted to be the time required to drill three or four holes for trolley hangers, to drill holes to take down a piece of loose roof, to drill shot holes in a roof fall, to make small spray applications of paint or sealing compound, etc.