Sources are inspected in order to verify that a company’s equipment is designed, installed , and operating in accordance with air pollution regulations and permits.

There are four ways that the compliance status of a source can be evaluated:
1.Engineering evaluations
2.Inspections
3.Source testing
4.Continuous emission monitoring (CEM)

Of these, only the third and fourth provide actual emission data measurements from a facility. Inspections will primarily be the focus of this section, but source testing and CEM shall be briefly discussed.

One of the best ways a source can stay in complaince with air pollution regulations is through preventative maintenance inspections. Companies that have efficient inspection and maintenance (I&M) programs tend to have fewer breakdowns, require fewer variances, have less down time and can save money. With an efficient I&M program, problems with equipment can be anticipated and surprising catastrophic failures can be reduced. A good I&M program also requires that neat, orderly consistent records of self-inspections be kept by the company.

Inspections of facilities may be performed for any one of the following reasons:
1.Compliance determination
2.Complaint investigation as a result of excess emissions or equipment malfunction
3.Source plan approval
4.Review or renewal of Permits

Compliance-type inspections only provide preliminary emissions assessments. Source testing is the method of determining compliance with an emission standard. Compliance inspections are usually unannounced so that a facility can be evaluated under normal operating conditions.

For other inspections pertaining to source construction, plan approval, permits, or “baseline type” inspections, the plant should be given sufficient advance notice so that qualified plant personnel can be present to provide the drawings, manuals and process information that may be required. Pertinent supportive evidence should be obtained prior to, during and following the source evaluation.