Document 9dOevyL3oe6XdE6mY2Zym8Qp

/ <A 3 Linda LaRose Attached is the slightly revised version of the guideline for silica abrasive blasting. On it I have highlighted the aeasures that are required because silica is present. My impression is that going to a non-silica grit does not buy significant relief in teras of activities. Many of the iteas identified are just part of doing the job in 1937. We just don't often see thea all written down in one place! Please advise if and when it would be desirable to issue such guidance. As usual, earlier the better especially i.f locations are putting programs in place IminiBice recreating the wheel). Again, this document is a tool froa which locations would develop or review their own procedures. cc: A.Schmit - DPMC B.Aurelius - Legal ABS-003254 LAM 0315667.026 deaFT z^z3/g^ HEALTH AND SAFETY NORKPRACTICE GUIDELINE FOR ABRASIVE BLASTING INSIDE VESSELS AND TANKS WITH SILICA I GENERAL 1. Each location conducting abrasive blasting with grit containing silica should establish local health and safety procedures for it's use. This is particularly iaportant\ where the abrasive blasting is to be conducted inside confined spaces such as vessels, or tanks. roosT \ocATioAS ( lnftve f -procCDur j The following outline illustrates some of the factors to be considered in establishing a local program. 2. While abrasive blasting in itself involves potential exposure to a variety of health and safety hazards, additional precautionary measure'should be considered where silica containing grits are used. Abrasive grits containing more than 17. free silica are considered relevant to this discussion e.g. "Starblast*. 3. The permissible exposure limit (PEL) associated with the use of silica containing grits is a primarily a function of the 1 silica present. For example, the pel for a grit containing 57. free silica would be: For "respirable* dust exposure 10 mg/m3 --------------- = 1.4 mg/m3 7. S i o 2 +2 This can be compared to a 5 mg/m3 limit associated with respirable "nuisance dust". 4. Due to the lower permissible exposure limits associated with silica, assuring compliance with the pel during abrasive blasting activities requires additional considerations for _ the integrity of the blasting hood, filtration systems on compressors used for breathing air and exposure .to downwind personnel. ; "j JjjlO iwpflCi r S>Tofr j 5. Where blasting is conducted inside vessels high dust levels should be assumed. With regard to downwind exposure potential, studies, have shown that exposure during (pure) silica sandblasting can occur for significant distances, e.g. 150+ feet. 6. While skin contact and ingestion of silica are not relevant routes of entry, appropriate hygienic procedures should be adopted to minimize gross contamination of skin and 0^ LAM 0315667.027 street clothing. This is particularly important if toxic metals are known to be present (e.g. nickel, chromium, lead, etc. 1. II TRAINING REQUIREMENTS 1. Eaployeesvwho engage in silica blasting operations should be trained in the specific health hazards associated with silica and the required procedures for safe blasting. Where contractor employees are used, training is the responsibility of the contractor employer. Whether or not this training has been accomplished should be ascertained by Shell. III PROCEDURES FOR ABRASIVE BLASTING INSIDE VESSELS 1. A pre-job orientation should be conducted with any contractor to be used 2. Warning signs and Isolation of the work area: As a minimum, the blasting area is to.be roped off or otherwise barricaded so as to isolate the immediate work area. Signs containing the following warning or its equivalent should be posted: Caution - Silica Sandblasting INHALATION HAZARD Respiratory Protection Required Note: Where the silica content is < IX , the sign in use should refer to abrasive blasting rather than silica sandblasting. The purpose of isolating the work area is to preclude pedestrian traffic from entering the restricted area without using respiratory protection. 3. Air compressors used to supply breathing air are to be located and maintained upwind of any dust emission sources. Requirements for air compressors include: a. An exhaust stack to be separated from the intake (Bft minimum). b. A particulate filter maintained in-line between the compressor and respirator c. Carbon monoxide measurements to be performed monthly on Xtijutrt. d Rc<^r' Swy4 ojX 10la6ALt, jr vW'rU.n-j ^ ,4uiiU<l Lwr b< ia piac. ABS-003256 LAM 0315667.028 each compressor used for breathing air or at least once during each different sandblasting job. 4. Hearing protection should be worn at all times during sandblasting and as nay be required where noise levels exceed 90 dbA. Hearing protection requirements may be more restrictive if the work shift is longer than 8 hours. 5. Where necessary to protect adjacent work ar^as, filters vr should be installed on vessel ventilatio'rT'Foppus blowers'.to minimize airborne'dust" levels outside the' vessel f>. Where applicable, the safety permit issued should state the required procedures. A copy of the required procedures should be provided to the contractor. OpTroHS \ * ScHtoocC. uJorlt ofP ISocXTE. p rea ToM bickers ? * cJcRecT c>HAoiT III RESPIRATORY PROTECTIVE EQUIPMENT 1. A program meeting the minimum requirements of the OSHA Respiratory standard should be followed. This program should include: a. Adequate cleaning of respiratory equipment. Generally blasting hoods used by a single employee should be cleaned at least weekly. Prior to each use the inside of each sandblasting hood is to be free of visible dust, and accumulation of dirt. f / ht*y wAy b. Fit testing of tight fitting (air purifying) respirators. Fit testing should not be conducted where facial hair exists between the sealing surface of the respirator and the face. c. Blasters are to wear NIOSH approved airline hoods. Typically such hoods require a minimum airflow of 4 cfo. Air supplied -equipment is also required of other personnel who enter vessels or tanks when blasting is underway. An air purifying dust maskmay have to be worn under .the -- airline hood of. the blaster as supplemental protection when blasting is conducted inside vessels with poor venti1ation. Ip 'proTrcuord uua ivc-A d. Potmen, other ancillary personnel, and inspectors are to wear at least NIOSH approved air purifying respirators inside the restricted area. Air purifying respiratory protection is to be worn by employees removing spent grit from vessels. e. For hot work environments, use of in-line air conditioning should be considered. ABS-0032R7 LAM 0315667.029 IV Exposure Monitoring Requirements a. Personnel and area monitoring should be conducted where necessary to verify the acceptability of the procedures put in place with regard to downwind personnel, placement of the barricade, exposure to the potman, etc. ivix-pr^T otJ V Bulk Silica Analysis 1. As a minimum the material safety data sheet for the abrasive grit in use should be obtained prior to commencing work. Where necessary information on the estimated level of silica and toxic metals should be obtained from the supplier. This should be supplemented by an analysis by Shell or an outside laboratory periodically for verification purposes. 2. Duponts' Starblast is primarily composed of naturally occuring mineral staurolite. It is mined and shipped from a .mineral deposit in Florida. The free silica content of their 1986 production averaged 2.5X. VI Medical Surveillance 1. Shell employees should be included in the Shell Special Medical. Survei11ance program for Silica where exposures exceed 1/2 the permissible exposure limit for at least 30 days per year. This includes pulmonary function exams, chest xrays, and appropriate other medical tests to detect any early signs of pulmonary effects. The facility Industrial Hygienist should be consulted with regard to the minimum entrance criteria and exposure potential. 2. Contractor management should be advised of the silica medical surveillance program that Shell has in place for it's employees. Note: no specific QSHA standards presently require medical exams for silica exposure although they have been recommended by NIOSH. "\ louJ ompAO / c.y P> 7 j VII Additional Information 1. Health and Safety Procedure Guidelines, No.5QBA on Sandblasting (issued July 1982) may be consulted for general safety considerations. 2. Abrasive Blasting Safety and Equipment Protection, a Dupont publication dated 5/2/85. ABS-003258 lam 0315667.030