It is not uncommon for the New Jersey Department of Health and Senior Services to receive inquires concerning the number of licensed Registered Environmental Health Specialists a local health jurisdiction should have on staff to adequately and professionally serve its community. Since 1942, there as been a general rule of thumb that one Registered Environmental Health Specialist is required for a population of 15,000. This ratio was derived from the Emerson Report on Local Health Units for the Nation. However, it is generally recognized that the duties and responsibilities of the Registered Environmental Health Specialist have evolved since that time. With the assistance of many local health officers and Registered Environmental Health Specialists, a simple series of calculations to determine a reasonable number of Registered Environmental Health Specialists necessary for a local health department has been developed.

It is important to emphasize that this is a managerial tool of suggested values which is available for your use if you decide to use it. It is not a formula without imperfections. There are many factors which have to be considered and many of these variables are not similar in each local health department. There are local health departments in a rural setting as opposed to an urban environment and there are municipal health departments, county wide units, and regional organizations all of which raise additional factors to consider.

We hope that the methodologies presented here will be of value to you. If you have any questions, feel free to contact the Division of Local Public Health Practice and Regional Systems Development at 609-292-4993.

Note: The following formula was devloped as part of a study conducted by Robert J. DiNunzio, New Jersey Department of Health and Senior Services, Division of Environmental and Occupational Health Services.

Step # 1. Determine total man hours per year.

Multiply work week by 52

Example: 35 hours x 52 = 1820

This figure of 1820 hours equals the total number of hours a registered environmental health specialist is available to work based upon a 35 hour work week.

Step # 2. Determine total man hours per year lost to vacation, sick leave, personal days, holidays, and training.

Multiply the number of days in each category by number of hours in a work day.

Example:	10 vacation days x 7	= 70 hours
	13 holidays x 7	= 91 hours
	7 sick days x 7	= 49 hours
	3 personal days x 7	= 21 hours
	7 training days x 7	= 49 hours
		280 hours

In this example, 280 hours per year are lost to the various types of absences. We have estimated the number of sick days the registered environmental health specialist uses as a yearly average. Training days also include time spent at association meetings, conferences, and seminars. Again this is also an average.

Step # 3. Determine actual man hours per year.

Subtract figure in Step # 2 from figure in Step # 1.

Example:	1820 or (52 weeks)
	- 280 or ( 8 weeks)
	1540 or (44 weeks)

Thus 1540 hours (44 weeks) is the actual amount of time a registered environmental health specialist works during a given year, taking into account the annual types of absences.

Step # 4. Determine number of hours spent for travel time and routine office hours.

A.) Multiply travel time x days x actual weeks of work per year

Example: 2 x 5 x 44 = 440 hours

B.) Multiply office hours x days x actual weeks of work per year

Example: 1 x 5 x 44 = 220 hours

C.) Add result from A & B

Example: 440 +220 = 660 hours

In this example, 440 hours are lost to travel time and another 220 are lost to routine office administration in this example. We have assumed that 2 hours are spent traveling daily and another hour is used for office time. Office time may be defined as office coverage, filing, researching, answering calls, maintaining records, etc.

Step # 5. Determine field hours available to a registered environmental health specialist per year.

Subtract figure in Step # 4 from figure in Step # 3.

Example:	1540
	- 660
	880

The figure of 880 hours represents the amount of field time available to a registered environmental health specialist for a year in which to perform his duties.

Step # 6. Determine yearly workload for registered environmental health specialists in the local health agency.

Multiply hourly average of each activity by average number of activities per year. Please refer to Appendix 1, Table of Suggested Hourly Averages for each activity.

Example:		Number of Activities	Hourly Average	Total Hours To Be Expended
Retail Foods	inspections	300	2.5	750
	re-inspections	75	2.0	150
Bathing Places	inspections	10	2.0	20
	re-inspections	2	1.0	2
Youth Camps	pre-ops	4	2.0	8
	initial	-		-
	re-inspections	-		-
Septic System	installations	25	10.0	250
Well	installations	30	3.0	90
Complaints	initial	1000	1.0	1000
	follow-up	250	.5	125
(complaints include housing, insects, heating, garbage, weeds, dogs, air pollution, etc.)				____
				2395

The figure 2395 hours is the total number of hours based upon past averages and experiences that this local health department spends in the field activities of registered environmental health specialists. Note: A reinspection rate of 25% was used in the case of retail foods, bathing places, and complaints.

Step # 7. Determine the number of registered environmental health specialists needed.

Divide the figure in Step # 6 by the figure in Step # 5.

Example:	2395	Total required hours ÷ 880 Total available field hours = 2.7
	/ 880	Total available field hours rehs
	2.7

For this example, it is concluded that this local health department should have three (3) registered environmental health specialists to adequately meet the needs of its community.