PARAPHRASE THE ANSWERS

1. Discuss the differences between ionizing and non-ionizing radiation. Provide one example of an occupational exposure to ionizing radiation and one to non-ionizing radiation. How do the differences influence the control methods used for these two types of radiation?

PLEASE PARAPHRASE/REWRITE ANSWER TO QUESTION 1 BELOW

There are two types of radiation exposure, which include ionizing radiation and non-ionizing radiation. The difference between the two is that ionizing radiations deposit sufficient energy in tissues to cause ionization and subsequent biological effects and non-ionizing radiation is not energetic enough to cause ionizations, but can cause thermal effects that could lead to subsequent biological effects (Mroszczyk, 2012).

X-ray Technicians employees who work in hospitals are exposed to ionizing radiation on a daily basis. X-ray machines produce high-energy ionizing radiation, which can penetrate the skin and cause damage to living cells through ionization. We all are exposed to non-ionizing radiation on a daily basis. Every time employees heat up food in the microwave or talk on cell phones during breaks, they are exposing themselves to non-ionizing radiation.

The three primary control methods for radiation are time, distance, and shielding. Ionizing radiation is very different from non-ionizing radiation because of their physical properties and abilities. For example, radioactive radiation can’t be turned off, but non-ionizing radiation can be reduced by turning any device that produces non-ionizing radiation when they are not in use (Mroszczyk, 2012). The fact that ionizing radiation penetrates the skin and non-ionizing radiation doesn’t is another consideration that should be taking into account when establishing control methods. Non-ionizing radiation can be controlled or reduced via shielding and controlling the distance, which would reduce the exposure. Ionizing radiation can be reduced and controlled by preventing unauthorized people from entering radioactive places, raising employees awareness on radiation, reducing the distance, using PPE, practicing great hygiene, using remote handling, shielding, and reducing the time employees are exposed to radioactive material (Mroszczyk, 2012).

Reference:

Mroszczyk, J. W. (Ed.). (2012). Safety engineering (4th ed.). Des Plaines, IL: American Society of Safety Engineers.

2. OSHA currently enforces an eight-hour, time-weighted average (TWA) PEL of 90 dBA, and uses a 5 dB exchange rate. NIOSH recommends an eight-hour TWA exposure limit of 85 dBA and a 3 dB exchange rate. The 85 dBA limit and 3 dB exchange rate is also used as a threshold limit value (TLV) by the American Conference of Governmental Industrial Hygienists (ACGIH) as well as many European countries. Discuss using a 5 dB exchange rate versus a 3 dB exchange rate in protecting workers’ hearing. Make a case for the use of either the 90 dBA PEL and 5 dB exchange rates or the 85 dBA REL and a 3 dB exchange rate.

PLEASE PARAPHRASE/REWRITE ANSWER TO QUESTION 2. BELOW

Basically, the OSHA noise standards make use of the noise dosimeter, which is the primary instrument for making compliance measurements. The standards has an exchange rate of 5 decibels, a frequency weighting of value A, a slow response rate, a criterion level of 90 dBA and a threshold of either 80 or 90 dBA. These two thresholds are used to measure dosimeter settings for noise exposure to different employees (Ostergaard, 1986). The 80-dBA thresholds is used to measure the noise exposure to those employees identified during the walk around whose exposure may exceed the 85 dBA time weighted average limit. The 85-dBA-threshold dosimeter is used to measure the noise dose of those employees identified during the walk around and their exposure exceeds 85 dBA.

NIOSH on the other hand have their exposures based on the 3-dBA exchange rates. The PEL is 85 dBA and the allowable TLVs for the noise range from 80 dBA for a period of 24 hours to 138 dBA for 0.11 seconds (OSHA, 1983). No exposure to continuous, intermittent or impact noise exceeds a peak C weighted sound level and is required for workers exposed to noise above the TLV levels. An example of the application of the 90 dBA PEL and 5 dB exchange rate is applied is the enforcement of this standard by the mining and safety authority in mines. The NIOSH REL formula is more logical because the allowable exposure time is cut in half for every 3-dBA increase in sound level. Using NIOSH formula will provide more protection for employees because it recommends the use of hearing protection at levels that are well below the enforceable OSHA PEL’s.

References

OSHA [1983]. CPL 2-2.35A-29 CFR 1910.95(b)(1), Guidelines for noise enforcement; Appendix A. Washington DC: U.S. Department of Labor, Occupational Safety and Health Administration, OSHA Directive No. CPL 2-2.35A (December 19, 1983).

Ostergaard PB [1986]. Physics of sound. In: Berger EH, Ward WD, Morrill JC, Royster LH, eds. Noise and hearing conservation manual. Akron, OH: American Industrial Hygiene Association.

3. Compare and contrast the primary exposure routes for hazardous materials. How does the route of exposure influence the type of control method that you would recommend?

PLEASE PARAPHRASE/REWRITE ANSWER TO QUESTION 3 BELOW.

The primary routes of exposure to hazardous materials include inhalation, absorption through the skin ingestion and injection. Inhalation is the primary route through which hazardous chemicals gain entry into the body. The materials that gain entry through this route are mainly air borne. Absorption on the other hand is carried out through the skin. The skin being the largest organ on the body is exposed to both liquid and airborne materials. This route can be very rapid especially if the skin has a cut or is abraded. A skin that is intact is a good barrier to the entry of chemicals (Mroszczyk, 2012). Ingestion involves the intake of chemically hazardous materials by swallowing. People tend to ingest harmful chemicals by eating, drinking or smoking of the contaminated food and drinks. Injections take place when a sharp object punctures the skin and allows the entry of chemicals and other infections into the body.

Different materials are controlled using different methods depending on the route of exposure. Materials that can gain entry into the body through inhalation can be controlled by wearing protective masks. Materials that can gain entry into the body through absorption via the skin are either liquid in nature or airborne. This can be controlled by ensuring that all open cuts on the skin are covered at all times and also wear protective clothing when handling hazardous materials (Mroszczyk, 2012). Entry through ingestion can be prevented by ensuring that food and drinks are covered at all times and should never be taken in hazardous environments. Finally, entry through injection can be prevented by ensuring that one wears shoes and protective clothing at all times when handling hazardous materials.

Reference

Mroszczyk, J. W. (Ed.). (2012).Safety engineering (4th ed.). Des Plaines, IL: American Society of Safety Engineers.

4. Compare two methods used to evaluate an employee's inhalation exposure to a hazardous material. Which method do you believe provides the most accurate measure of an employee's exposure?

PLEASE PARAPHRASE/REWRITE ANSWER TO QUESTION 4 BELOW.

Air sampling is useful in evaluating an employee’s inhalation exposure. There a number of different techniques that is used to determine the concentration of toxic substances, flammable materials and airborne contaminants. There are two different sampling techniques which include Grab sampling and integrated sampling.

Grab sampling is basically short term and take samples of toxic substance that are usually known or suspected and these tests are designed for specific substances. The most common method of grab sampling involves the use of a hand pump with a sample tube for some specific substances and the tube must be calibrated to indicate the concentrations. The sample tube changes color as the particular substances enter the tube. The accuracy of this method is questionable. Grab sampling are fast, inexpensive and can be done at any location at any time by an employee with relatively little training.

Integrated sampling on the other hand is carried out continuously over a period of time in order to obtain a time weighted average exposure. This sampling technique is more accurate as compared to grab sampling but they give no indication of peak concentrations.

In my opinion, I believe that this technique gives the most accurate measures of employee exposure since it is done on a continuous basis. I also think that grab sampling should be used together with integrated sampling in order to obtain time weighted average and maximum exposure

Reference

Mroszczyk, J. W. (Ed.). (2012). Safety engineering (4th ed.). Des Plaines, IL: American Society of Safety Engineers.

PLEASE WRITE ANSWER FOR QUESTION 5 BELOW

5. OSHA updated 29 CFR 1910.1200, the Hazardous Communication standard in 2013. The update included new required elements for labels on hazardous materials. Discuss how the new labels compare to NFPA, HMIS, and DOT labels. Of the four labeling systems, which do you believe provides the most information about chemical safety to employees and why?