Document 37bw4N378qq2pOVmgodwGm3Ya

23208 RULES AND REGULATIONS * As amended, Table G-3 reads follow. Tarm; O-3--MtNBBAT. Tm??tr as 3ubsU\nc Mppe.t * Mg/M* Crystalline: Uttarix Cr^pirabi*'}. _ .... lifiO 1 JOrog/M4 * %8lO+ 1 Quarts {total dust)................................. 30tng/M` Crlstobullte: Use Y) the x'ftluo'calculated from the notint. or mass formulae for miorla. TrUlymlle* Tjsoj^tlie-value calculated from the for* mulae tor quarto. Amorphous, Including natural dlftfomncoous earth......... .. %S,0> + C 20 gOing/M* %$>Ox etHoatcs (less than 1% crys talline silica): Mina........................................ 20 Soapstone................. 'A' Talc................. Portland cement.................. & 60 OtBphlte (natural).................. 16 Coal dust Iraspliabl* fractiou less than 6% SlOj)..........-........................ For more than 5% SlOj.............. ................ 2.4nig/M* or tOrag/M* Inert or Nuisance Dust: Uftsplrable fraotlou.......... Total dust-.................. .... It tmg/M1 60 16idb/M* Not*: Conversion factors-- tupj>cfX35.3*= million particles i>cr cttVdo mater Bpartlidos par c.c. Millions of parUeln? twr cubic toot of air, based on hnplnger samples counted by ligUl-flold uvjmies. t Tbo percentage of crystalline slllc-a la the formula Is the Amount determined from alr-bamc samples, oicept in those Instances In- which other method? have bo*n shown to be applicable. 1 As deterzoinod by the membrane filler method at 430xphase contrast magnification. m Both concentration end percent quarts for the appli cation ot this limit are to be determined from the fraction passing a edTAw%lee.tor with the following characteristics: Aerodynamic, dlamnlcr (rniit density sphere) 2 2.5 a.fi 6.0 10 Percent passing selector on 76 ' 25 0 The measurements under this note retor to the use of on A EC instrument, ff the respirable fmotion of coal dust is determined with a MICE Uie figure corresponding to thAl of 2,4 Mg/M3 in the tabid for coal dust Is 4 A Mg/M, . 2. A new 5 1910.93a is added to Part 1910. The new 1910.93a reads as follows: 1910.93a Atin'stos ilusl. (a) The 8-hour time-weighted aver age airborne concentration of asbestos dust to which employees are exposed shall not exceed 5 fibers per milliliter greater than 5 microns in length, as de termined by the membrance filter method at 400-450 x magnification (4 millimeter objective) phase contrast illumination. Concentrations above 5 fibers per milliliter:but, not to exceed 10 fibers per milliliter, may be permitted up to a total of 15 minutes in an horn- for up to 5 hours in an 8-hour day. (b) Engineering methods, such as but not limited to, enclosure, vacuum sweep ing. and local exhaust ventilation, shall be used to meet the exposure limits pro scribed in paragraph (a) of this section. Where sueh engineering methods are not feasible, or do not otherwise reduce the concentrations below those prescribed in paragraph (a) of this section, respira tory protective devices shall be provided and used in accordance, with paragraph (c) of this section. U'.i'l) til When the limits of ex posure to asbestos dust prescribed in paragraph la) of this section are exceedfxt and when engineering controls required by paragraph < b i of this sec tion are not feasible or do not otherwise re duce the concentration o asbestos dust below those prescribed in paragraph (a) of this section, the employer shall re quire the use ol respiratory protective de vices. Tire selection of respiratory protective devices shall be limited to those specified in the remaining subparagraphs of this paragraph f c >. (il) -lire employer shall require that each employee test his respiratory pro tective derice before each use in order to insure a proper lit according to the manufacturer's instructions. The em ployer shall further provide for effective training or supervision of employees in the testing of respiratory protective de vices for fit before their use. (2) For an atmosphere containing not more than 25 fibers per milliliter greater than 5 microns in length over an 8-hour average, or more than 50 fibers per milli liter over any period of 15 minutes, a reusable or single-use filter type respira tor, operating with negative pressure during the inhalation phase of breathing, approved by the U.S. Bureau of Mines under the provisions of 30 CFR Part 14 (Bureau of Mines Schedule 2IB), or a valveless respirator providing equivalent protection, shall be used. (3) For an atmosphere containing not more than 250 fibers per millilter greater than 5 microns in length over an 8-hour average, or more than 500 fibers per milliliter over any period of 15 minutes, a powered filter positive pressure res pirator approved by the U.S. Bureau of Mines under the provisions of 30 CFH Part 14 (Bureau of Mines Schedule 21B) shall be used. <4) For an atmosphere containing more than 250 fibers per milliliter greater than 5 microns in length over an 8-hour average a type C positive pres sure supplied-air respirator approved by the U.S. Bureau of Mines under the pro visions of 30 CFR Part 12 (Bureau of Mines Schedule 19B) shall be used. (5) The employer shall establish, a respirator program in accordance with the requirements of American National Standard Practice for Respiratory Pro tection Z88.2--1969. (6) The respirators provided each em ployee shall be properly inspected, cleaned, repaired and stored. (d) (1) When an employer has em ployees who are exposed to asbestos dust exceeding the limits prescribed in para graph (a) of this section und the ex posure results from the operations de scribed in the remaining subparagraphs of this paragraph (cl), the employer shall comply with the requirements of these subparagraphs relating to the operations involved. The requirements of this para graph are in addition to those prescribed in paragraph (b) of this section. (2) All hand- or power-operated tools which produce asbestos dust such as, taut not limited to, saws, scorers, abrasive wheels, and drills shall be provided with local exhaust ventilation and dust col lectors in accordance with the American National Standard Fundamentals Gov erning the Design and Operation of Local Exhaust Systems; ANSI Z9.2--1971. ' (31 Employees exposed to the spray in r of asbestos or the demolition of pipes, structures, or equipment covered or in sulated with asbestos shall be provided with respiratory protective devices in accordance with paragraph (c)(4) ot this section. <e: Asbestos cement, mortar, coatings. grout, and plaster shall be mixed in closed bags or other containers. <f) Asbestos waste and scrap shall be collected and disposed of in sealed btins or other containers. <' All cleanup of asbestos dust and blowing shall be performed by vacuum cleaners. No dry sweeping shall be per formed. 3. Section 1910.12 is amended by changing paragraph (a) in order to apply the emergency standard prescribed in the new 5 1910.93a, which is published in this document, to construction work which is 'subject to the Act. The amendment is necessary in light of the rule of regula tory construction set forth in 5 1910.5>'c. >. As amended, 1910.12 reads as follows; 1910.12 Construction work. (a)(1) Adoption mul extension of es tablished safety and health standards for construction. The standards pre scribed by Fart 1518 of this title and iti effect on April 28, 1971, are adopted as occupational safety or health standards under section 6(a) of the Act and shell apply. Recording to the provisions thereof, to every employment and place of employment of eveiy employee en gaged in construction work. Each em ployer shall protect the employment and places of employment of each of fur, employees engaged In construction work by complying with the appropriate standards prescribed by this paru.irn.ph <2) Tire standards prescribed in 5 1518.55(c) of this title shall apply iri tire case of the exposure of anv em ployee in construction work to airfxwruasbestos dust. * * Effective date. These auicri'ivirr.ts shall become effective immf ckHUiy utku: publication in the Feuctm liKoivjrn (12-7-71). (Sec. (cl, fyl suit. 1596. 29 DSC <V-v ,,>retary'a Order No. 12-71,3C F.R nv -t Signed at Washington. DC. lid:. 2d day of December 1971. G. C. Guenther Assistant Secretary of hobo- (Fit Doc.71-17883 Filed 12-0 71 8 47 J FEDERAL REGISTER, VOL 36, NO, 234--TUESDAY, DECEMBER 7, 1971 HWBUI0005250