Recognizing IH hazards
Ultimately, industrial hygiene is the anticipation, recognition, evaluation and control of workplace health hazards. Spending more time in the â€œrecognitionâ€ step of the industrial hygiene process can help you properly manage your IH program. Managing the program requires proper planning and using your limited safety and health resources wisely. There is a logical planning sequence that needs to be followed.
Information gatheringFirst, gather information about the facility from as many sources as possible, such as EHS due diligence reports and audits, environmental assessments and previous industrial hygiene monitoring results. Other records to review are injury and illness reports, medical monitoring data, and, yes, employee complaint records.
Interview the facility manager, supervisors and a representative number of workers from all areas of the facility. Interviewing representative workers, who are not complainers, will ensure an accurate picture of the overall facility. Ask workers about non-routine events. Discuss with maintenance personnel equipment failures, leaks and other frequent maintenance activities.
Gather information about the chemicals and processes used at the facility. Review chemical inventory listings. Study the process flow diagrams and identify the flow and volume of materials, intermediate products and by-products. Look at types of equipment in the processes and at all points where materials can be released and personnel potentially exposed.
The purpose of gathering this information is to ensure that all potentially harmful substances are identified.
Identify potential exposuresIndustrial hygiene pros must also estimate the magnitude of personnel exposures. This can be done by determining the general toxicity (high/medium/low) of the substances from the MSDS (Material Safety Data Sheet) or toxicological literature. This evaluation must include the number of people exposed and the length of time they are exposed.
Conduct a â€œwalk aroundâ€ survey of the facility to ensure the information and data that was assembled in the information gathering phase matches the work practices within the facility. Look for visible leaks, spills or emissions from process equipment. Inspect work areas for vents, settled dust, airborne mists, open containers from which liquids may evaporate, and other sources of releases. Review areas of the facility where heating and drying take place, which makes substances more volatile.
Review the various job functions at the facility to determine which ones require the most material handling activities. Be especially alert to job functions that are likely to create airborne exposures â€” jobs that involve grinding, scraping, sawing, cutting, sanding, drilling, spraying, measuring, mixing, blending, dumping, sweeping, wiping, pouring, crushing, filtering, extracting and packaging, to name a few.
Be alert to engineering and ventilation control system failures. Look for visible leaks from ventilation hoods, duct work and dust collectors. Watch for ventilation hoods that are located too far from the source. Check for ductwork that is clogged, dented or missing, or where the ventilation system is broken.
Search for areas within the facility where personnel are at risk of absorption of harmful substances, particularly where chemicals are being handled that have a skin notation on their OSHA-PEL (Permissible Exposure Limit) or ACGIH-TLV (Threshold Limit Value). It is safest to assume all liquids will penetrate the skin.
Exposures can also come through inadequate personal hygiene work practices. Search for areas where personnel may be exposed to substances that can be directly ingested from their hands or face through eating, drinking or smoking.
Decide what to sampleOnce all this information has been gathered and potential personnel exposures identified, a decision must be made about which substances to sample. It would be nice to sample for everything, but this is typically not possible due to limited resources.
Conduct a risk assessment that incorporates such factors as the toxicological nature of the substance, the magnitude of the estimated personnel exposures and the number of personnel exposed. The risk assessment must also include the variability and frequency of potential personnel exposures.
Once the risk assessment is completed, take a realistic look at the amount of resources available to perform the industrial hygiene sampling, such as time, money, equipment and available personnel. Addition-ally, consider if there are alternatives to conducting the sampling and still collecting the personnel exposure information desired. There may be sampling data available through a trade industry association, a similar operation within the company or perhaps sampling information from another company. Health and safety professionals often share information â€” not the actual sampling results, but theyâ€™ll discuss in general terms the exposure levels within certain operations.
How will sampling be done?Once you decide what must be sampled, you need to determine how the sampling will be done. Can additional resources be obtained? Should the sampling be performed over a short term or long term timeframe? Will personal or area samples be collected? Which sample collection method would be most appropriate for your situation?
There will always be limitations to the sampling performed. A complete picture of potential personnel exposures may not be provided due to limited resources and other factors. So, it is critical to use the time and money available efficiently, focusing on those substances that actually present a risk to personnel versus those substances that are merely an irritant to the complainers. There may be people at the facility who have never complained and are being exposed to harmful substances â€” substances with poor warning properties and that have never been evaluated and may have caused severe health effects.
It is up to the safety and health professional to actively manage the industrial hygiene program and recognize and evaluate the harmful, but previously unrecognized, substances â€” not just the ones that are noticeable by the complainers or highly regulated by the agencies.
SIDEBAR: IH sampling: Donâ€™t be fooledâ€¦When conducting industrial hygiene sampling, safety and health pros tend to sample those substances with strong warning properties â€” a noticeable odor or a visible gas or dust, because these are the substances that are easily detected by humans, particularly the complainers. The chemicals that should be of equal or even more concern are those substances that are not easily detected by humans through smell, taste, sight and so on.
Another group of substances that are typically sampled extensively are those covered by a specific OSHA regulation, i.e. lead, cadmium, asbestos and so on. It is important for safety and health pros to gather information about all substances, not just those that spark complaints or are highly regulated.