Steinsvåg Kjersti, Galea Karen S, Krüger Kirsti, Peikli Vegard, Sánchez-Jiménez Araceli, Sætvedt Esther, Searl Alison, Cherrie John W, van Tongeren Martie
Statoil ASA, Oslo, Norway.
Ann Occup Hyg. 2011 May;55(4):347-56. doi: 10.1093/annhyg/meq097. Epub 2011 Jan 19.
Workers in the drilling section of the offshore petroleum industry are exposed to air pollutants generated by drilling fluids. Oil mist and oil vapour concentrations have been measured in the drilling fluid processing areas for decades; however, little work has been carried out to investigate exposure determinants such as drilling fluid viscosity and temperature. A study was undertaken to investigate the effect of two different oil-based drilling fluid systems and their temperature on oil mist, oil vapour, and total volatile organic compounds (TVOC) levels in a simulated shale shaker room at a purpose-built test centre. Oil mist and oil vapour concentrations were sampled simultaneously using a sampling arrangement consisting of a Millipore closed cassette loaded with glass fibre and cellulose acetate filters attached to a backup charcoal tube. TVOCs were measured by a PhoCheck photo-ionization detector direct reading instrument. Concentrations of oil mist, oil vapour, and TVOC in the atmosphere surrounding the shale shaker were assessed during three separate test periods. Two oil-based drilling fluids, denoted 'System 2.0' and 'System 3.5', containing base oils with a viscosity of 2.0 and 3.3-3.7 mm(2) s(-1) at 40°C, respectively, were used at temperatures ranging from 40 to 75°C. In general, the System 2.0 yielded low oil mist levels, but high oil vapour concentrations, while the opposite was found for the System 3.5. Statistical significant differences between the drilling fluid systems were found for oil mist (P = 0.025),vapour (P < 0.001), and TVOC (P = 0.011). Increasing temperature increased the oil mist, oil vapour, and TVOC levels. Oil vapour levels at the test facility exceeded the Norwegian oil vapour occupational exposure limit (OEL) of 30 mg m(-3) when the drilling fluid temperature was ≥50°C. The practice of testing compliance of oil vapour exposure from drilling fluids systems containing base oils with viscosity of ≤2.0 mm(2) s(-1) at 40°C against the Norwegian oil vapour OEL is questioned since these base oils are very similar to white spirit. To reduce exposures, relevant technical control measures in this area are to cool the drilling fluid <50°C before it enters the shale shaker units, enclose shale shakers and related equipment, in addition to careful consideration of which fluid system to use.
海洋石油工业钻井部门的工人会接触到钻井液产生的空气污染物。几十年来，人们一直在测量钻井液处理区域的油雾和油蒸气浓度；然而，对于诸如钻井液粘度和温度等暴露决定因素的研究却很少。在一个专门建造的测试中心的模拟页岩振动筛房内，开展了一项研究，以调查两种不同的油基钻井液系统及其温度对油雾、油蒸气和总挥发性有机化合物（TVOC）水平的影响。使用一种采样装置同时采集油雾和油蒸气浓度样本，该采样装置由一个装有玻璃纤维和醋酸纤维素滤膜的密理博封闭盒式采样器以及一个备用活性炭管组成。通过PhoCheck光离子化检测器直读仪器测量TVOCs。在三个不同的测试阶段评估了页岩振动筛周围大气中的油雾、油蒸气和TVOC浓度。使用了两种油基钻井液，分别称为“2.0系统”和“3.5系统”，其在40°C时基础油的粘度分别为2.0和3.3 - 3.7 mm² s⁻¹，温度范围为40至75°C。总体而言，2.0系统产生的油雾水平较低，但油蒸气浓度较高，而3.5系统则相反。在油雾（P = 0.025）、油蒸气（P < 0.001）和TVOC（P = 0.011）方面，发现钻井液系统之间存在统计学显著差异。温度升高会增加油雾、油蒸气和TVOC水平。当钻井液温度≥50°C时，测试设施中的油蒸气水平超过了挪威30 mg/m³的油蒸气职业接触限值（OEL）。由于这些基础油与白酒精非常相似，因此对以40°C时粘度≤2.0 mm² s⁻¹的基础油的钻井液系统的油蒸气暴露合规性测试做法提出了质疑。为了减少暴露，该领域的相关技术控制措施包括在钻井液进入页岩振动筛单元之前将其冷却至<50°C，封闭页岩振动筛及相关设备，此外还要仔细考虑使用哪种流体系统。
