When You Need an IH

You will need to have the knowledge and courage to realize when you need to call an IH to help you. IHs have very special and specific training related to workplace environmental evaluations and assessments as well as the ability to make recommendations on controlling workplace hazards. 

An IH concerned about exposure hazards associated with your workplace must be familiar with the various activities and processes that you have. The classic approach of recognition, evaluation, and control strategies used by IH applies to all industries. Sometimes exposures can be attributed to the job. For example, for a worker using a solvent to clean a piece of mechanical equipment, the IH may need to investigate organic vapor exposure, correct personal protective equipment use, surrounding environment, and possibly personal hygiene conditions. 

Hazards involving normal work activities can usually be predicted by a trained IH. It is, however, very unpredictable how much airborne exposure a worker is subjected to from a particular source. Many times the same type of work conducted at one site is much different from an exposure condition at another. Inside exposures will remain more constant than outside where wind and weather conditions play a major role. For example, asbestos abatement work that is conducted in a controlled atmosphere inside should remain fairly constant if work practices such as negative air filtration are used and surfaces are wetted properly. Conversely, work on an asbestos roof on the outside, even though there is a difference in the type of asbestos, will depend more on weather conditions. Work practices such as location of the worker in relationship to the wind (up- or downstream) and how intact the shingles are as they are removed also play an important part in overall exposure. The more broken up they are the more likely an asbestos exposure will result. Although inside exposures sometimes can vary vastly with the size of an area and individual work practices, it is not usually expected to be that way. 

If the airborne exposure is to be determined for a particular job, the IH must be prepared to monitor quickly. The next day may be too late. Concentrations usually need to be high to find TWAs that exceed OSHA PELs. More often than not the construction worker is not conducting the same job for an 8 h period. Many tasks are usually required to accomplish a day s work, which also makes it difficult to evaluate a particular hazard. A worker welding, cutting, and burning all day on an outside project such as a painted bridge may have no exposure or wind up in the hospital undergoing chelation therapy with a blood lead level in the hundreds. Many variables affect the potential and real exposure levels such as work habits, weather, and type of paint on the steel as well as personal protective equipment used. 

It is most appropriate to consult an IH when selecting personal protective equipment for a specific use such as which gloves are best for use with certain chemicals and which respirator should be used for exposure to a specific chemical. The IH is the only one who has the training and experience to determine the risk for exposure, the environmental sampling that is needed, the sampling techniques to use, and the controls that should be in place to prevent further exposure. 

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