Given the recent request to assist a local chemical manufacturer with OSHA compliance, one of the major issues to tackle will be whether the company is required to comply with OSHA Methylene Chloride standard. The company uses Methylene Chloride (MC) chemical to manufacture a special paint stripper for the Department of Defense (DOD). Methylene Chloride is a colorless, volatile solvent, with a chloroform-like odor. Exposure to this chemical increases the risk of developing cancer, and diseases of the liver, heart and CNS (central nervous system). Exposure occurs via inhalation, and direct contact and absorption through the skin. The immediate effect of exposure is irritation (Osha.gov, 2016).
In order to determine whether the plant must comply with OSHA standards regarding MC, several evaluation checks need to be done against the prescribed OSHA Methylene Chloride standard - 1910.1052. The first check involves analyzing all the conditions necessary for the chemical agent to be released, and the state in which it is released e.g. vapor, fumes, liquid, etc. In this case, the process conditions that would lead to the release or discharge of the chemical are analyzed especially given that the chemical is usually discharged via pressurized spraying as a mist which could be hazardous to the employees working it. It is, therefore, necessary to note if employees have been provided with proper safety gear such as protective clothing and gas masks to handle the chemical and prevent exposure through inhalation. The second check would involve the storage conditions for the chemical which includes the storage areas, container suitability, and flammability issues. The third determining factor is the transport and disposal considerations for MC in relation to compliance with waste disposal regulations, containing spillages, and proper disposal in case of emergency. Finally, there is need to evaluate the availability of fire safety measures to deal with fire emergencies. This includes availability, suitability and proper location of firefighting equipment to be used in case of fire (Plog & Quinlan, 2012).
If all the above checks are made and it is found that the plant has made provisions for all the safety measures, chemical handling and emergency response requirements, then the plant could be said to be compliant with OSHA Methylene Chloride standard - 1910.1052. However, if some of the inspected areas do not meet the standard requirements and endanger employee safety, then the plant must enforce measures to fix these issues for them to be considered OSHA compliant.
References:
Osha.gov. (2016). Methylene Chloride. - 1910.1052 Standard. Osha.gov. Retrieved 28 March 2016, from https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=10094
Plog, B., & Quinlan, P. (2012). Fundamentals of industrial hygiene (6th ed., pp. 490-494). Itasca, Ill.: National Safety Council.
Direct reading instrument for OSHA compliant confined space atmospheric testing program:
There are different types of direct reading instruments used in confined space atmospheric programs as part of OSHA compliance. As the safety professional at a small chemical processing plant and responsible for the confined space program, I shall discuss and propose suitable equipment to be used in the confined spaces at the site. These spaces include large storage tanks located above ground, holding petroleum distillates toluene and xylene.
The most appropriate direct reading instrument for this scenario is a combustible gas monitor. There are three different types to choose from i.e. thermal conductivity detector, metal oxide semiconductor (MOS), and catalytic combustible gas sensor. Each of these types of sensors is compound dependent but in a case where the gases are combustible such as toluene and xylene, catalytic combustible gas sensors are preferred (Plog & Quinlan, 2012).
The sensors are used in explosive conditions and in this case, the above ground tanks used to store xylene and toluene are the perfect environment for their use. The tanks are exposed and get heated by the sun causing the gases to expand, and this could be hazardous if not monitored. These sensors detect combustible gases by actually combusting gases in their sensor chambers. The sensors comprise a flame arresting material and two encasing chambers each containing a wire filament coil. One chamber allows air in and has palladium or platinum coil, and the other is sealed to prevent air from entering. The coil in the second chamber is not coated. Bothe coils are heated to temperatures above 500 degrees Fahrenheit, and when the combustible gases get exposed to the coil, they raise the bead temperature higher. The electrical resistance of the coil and the change in temperature are recorded and displayed as percentage Lower Explosive Limit (LEL) (Cdnsafety.com, 2016). The combustion chambers are designed such that the gases only burn inside the chamber and do not ignite the rest of the gas in the environment.
Conclusively, catalytic combustible gas sensors provide good linearity and respond to most combustible gases. Since the change in resistance percent LEL is quite minimal, catalytic sensors work best in high gas concentrations (about 1000 to 50000 PPM). They are not reactive in low concentrations below 200 PPM and are therefore useless in detecting toxicity levels (Cdnsafety.com, 2016). However, since they are used in the actual tanks containing the distillates, then they are bound to be quite effective.
References:
Cdnsafety.com,. (2016). Selecting gas detectors for confined space entries. Cdnsafety.com. Retrieved 28 March 2016, from http://www.cdnsafety.com/articles/selecting_gas_detectors.htm
Plog, B., & Quinlan, P. (2012). Fundamentals of industrial hygiene (6th ed., pp. 490-494). Itasca, Ill.: National Safety Council.
