Human Exposure and Environmental Release (Continuation Sheet for page 

9 of PMN Form) 

Section A - - Industrial Sites Controlled by the Submitter

2. Occupational Exposure – during the production of 

This attachment is the basis for the information submitted under “Occupational Exposure” of this 

PMN for the use New Chemical Substance (NCS) at plant. 

General Process Information

The production of is carried out in several continuous processing and distillation 

units. Due to the potential hazards associated with the use of flammable, corrosive, or toxic 

substances, guidelines require that all vessels or other units be operated as a 

“closed” system and inerted with nitrogen during normal charging, reaction, or transfer 

operations and also be process-piped wherever possible. It should also be noted that the NCS 

processing with the most potential for chemical exposure is taking samples. However, to insure 

against exposure, all chemical operators are required to use appropriate personal protective 

equipment for all sampling operations and all plant sampling operations utilize closed sampling 

systems. The trucks used for shipping the for sulfur recovery are sampled with 

PPE (gloves and eye protection).

If inspection or repairs are required during production, which is a rare occurrence, these will only 

be undertaken after a thorough clean out of the involved equipment according to corporate 

standard operating procedures including the need for an approved safety work permit. In 

addition, all maintenance personnel must use all protective equipment as outlined in the 

associated standard operating procedures. Thus, there is no potential of exposure to the NCS 

for these workers. There is also no potential of exposure for supervisory personnel as they are 

only rarely in close proximity to any chemical processing area, and in the rare instances that 

they are, they are required to wear appropriate protective equipment. 

There is a potential for exposure to for the laboratory technicians who assay the 

process samples some of which contain the NCS. However, to minimize this exposure, all 

laboratory technicians are required to wear appropriate personal protection equipment and to 

follow prudent laboratory practices. 

Based on the above, worker activities required for the use of the NCS, which 

result in the potential for occupational exposure, are described in further detail the following 

sections of this attachment. 

Occupational Exposure 

2(1): Worker Activities (Involving Exposure),

2(3): Protective Equipment/Engineering Controls, &

2(5): Physical Form(s)

Routine Batch Sampling: Routine sampling activities will occur at various times in the 

continuous processing. During sampling, the material handlers/chemical operators will wear 

appropriate protective equipment (gloves and eye protection). A description of each likely 

sample stream including the number of samples to be taken, the physical form, stream 

temperature, and percent uracil NCS in the stream are listed below. In addition to the routine 

number of samples to be taken for each batch, the number of samples that may be taken during 

the start-up of a campaign is also shown in the Sampling Table below.
 Routine Number

 (Start-up Number) Physical Temper- % NCS 

Process Step Stream Description of Samples Form ature in Stream

NCS 1/day Liquid Ambient 100% 

NCS 1/day Liquid 250 oF 100% 

NCS (1)/day Liquid ~375 - 390 o

F 100% 

NCS 1/day Liquid 375 – 390 oF 100% 

NCS (1)/day Liquid ? oF 100% 

NCS 3/week Liquid 150 oF 100% 

Note that a sample is normally taken from ; however, if is out of service, the 

sample is taken from . A sample is normally taken from , which is connected to 

the bottom of . If is out of service, the sample is taken from bottoms. A 

sample is normally not taken from .

As indicated in the Sampling Table above, there is a potential for exposure during routine

sampling of the process streams to produce the 

Sample Analysis: To minimize exposure to any chemicals, laboratory technicians prepare 

samples for analysis in a chemical fume hood or with local ventilation. Laboratory technicians 

are also required to use protective equipment such as safety glasses or splash goggles, gloves, 

laboratory coats or aprons for any sample analysis. 

A description of the samples to be assayed at various times during a day including the physical 

form is shown in the Sampling Table above. However, for these samples, the temperature at the 

time of exposure would be “Ambient”.

2(8) Occupational Exposures: Maximum Number of Workers in Each Activity

The chemical operators and laboratory technicians work 12 hour shifts on a 4 shift schedule 

which runs seven days/week. This rotation results in that a given chemical operator/laboratory 

technician is working 10.5 days every two weeks. This is approximately 75% of the 

manufacturing days. For the production of it is assumed that five chemical 

operators, but only two take samples and 3 laboratory technicians, will be required for each 12-

hour shift. Thus, potentially 2 chemical operators and 3 laboratory technician may be exposed 

to the NCS during each 12 hour shift. 

Based on the above analysis, activities for which occupational exposures can occur and the 

number of employees that could potentially be exposed are summarized below:

1. Routine batch sampling involves 8 chemical operators (2 chemical operators for each of the 

4 shifts) 

2. Sample analysis involves 12 laboratory technicians (3 for each of the 4 shifts)

Thus, the maximum number of different workers who could potentially be exposed during the 

use of the NCS would be 20 (8 chemical operators/material handlers and 12 laboratory 

technicians). 

2(10) Occupational Exposure: Maximum Duration of Exposure in Hours/Day

The maximum duration of exposures during the use of the PCM NCS is estimated based on the

operation description. It should be noted that any actual exposure is not the duration of the 

activity itself, since the latter information is of limited value in evaluating the extent of the 

exposure.
Routine Process Sampling: As indicated previously, the present sampling scenario for the 

process shows that the expected number of samples/day involving the significant potential for 

exposure to is 4/day. Thus, normally the 2 chemical operators working over the 

course of a 12-hour shift or 0.5 day will conduct 2 sampling operations. The maximum 

exposure for chemical operators during a batch sampling operation is expected to be 

approximately 15 minutes per sample. Assuming that each chemical operator performs a 

similar number of sampling operations, this translates to 1 sampling operations/day/chemical 

operator (2/2). Thus, the duration of exposure for each of the 8 chemical operators is estimated 

to be 0.25 hours/day/chemical operator (1x0.25).

Sample Analysis: Maximum exposure for the laboratory technicians during any single sample 

analysis activity is expected to be approximately 20 minutes per sample. As indicated above, the 

expected number of samples/year involving the potential for exposure to is 3x330 

days = 990 routine samples. Thus, the three laboratory technicians working over the course of a 

12-hour shift will assay 1.5 samples (3 x 0.5 day). Assuming each laboratory technician performs 

a similar number of analyses, this translates to 0.17 analyses/day/laboratory technician (0.5/3). 

Thus, the maximum daily exposure for each of the laboratory technicians is estimated to be 0.06

hours/day/laboratory technician (0.17x0.333 = 0.06).

2(11) Occupational Exposure: Maximum Duration of Activity in Days/Year

It is estimated that the use of the NCS on this scale could require up to 330 days at the one year 

maximum volume anticipated. Using this number of manufacturing days and assuming each 

chemical operator and laboratory technician works on approximately 75% of the manufacturing 

days (see the previous page for how this % was arrived at), these workers can be exposed to 

the PCM NCS on approximately 251 days each year. 
Part II - - Human Exposure and Environmental Release (Continuation Sheet 

for page 9 of PMN Form) 

Section A - - Industrial Sites Controlled by the Submitter

3. Environmental Release and Disposal – For the production of 

The following discussion addresses the waste streams from production of the NCS and how 

these waste streams are handled and disposed. 

3(1) Identity of the Release Numbers (Release Points)

During normal production, there are no releases of the NCS to the environment. Since all the 

organic streams that comprise the come from phase splits from an aqueous 

phase, it is possible that a small amount of remain in the aqueous layer. All the 

aqueous waste is disposed of on-site via the deep well. Before the aqueous is sent 

to the deep well, there is a final split of residual organic material that is added to the rest of the 

Vessels that contain are only cleaned at the end of a campaign or before 

maintenance. When they are cleaned, they are cleaned with caustic and steam, and the clean 

out solution is transferred to the aqueous waste system for eventual on site deep well 

injection.

Industrial Hygiene Plan

The Industrial Hygiene Program at all plants is comprehensive and covers all the 

requirements outlined by the corporation as well as OSHA regulations. Written standards, 

tailored to the specific needs of each plant, have also been documented.

Specific aspects of the program include:

1. Appropriate personnel monitoring of employees for airborne contaminants (dusts and 

vapors) and physical hazards (noise). Exposure results are posted in the operating areas 

monitored, and reports are issued directly to the employees being monitored.

2. A record system, including an employee file to maintain documentation of all industrial 

hygiene related training and respirator fit testing.

3. Control over all chemical substances introduced into the plant, including approval prior to 

such use.

4. Listings of chemical exposure by job description (as outlined in Industrial Hygiene 

Exposure Assessment Program) for the chemicals that are handled.

5. Respirator training and fitting program.

6. Basic design criteria such that all processes are carried out as closed vessel operation to as 

great an extent as possible.

7. Use of local exhaust ventilation and personal protective equipment where opening of 

otherwise closed system is required, e.g. for sampling, charging, transfer operations, 

equipment inspections/flushing etc.

8. Approved areas for eating and smoking.
9. A personal hygiene and clothing program under which employees are given freshly 

laundered clothing to start each shift and encouraged or required to shower and change 

clothing at the end of the shift.

10. Written operating instructions used by production employees which outline the hazards of 

each chemical substance used in the process and the special precautions which must be 

followed in handling it.

11. A system of safety work permits used by maintenance employees, which outline special 

precautions, required for each job.

12. Monthly plant keeping inspections, which are performed in each operating department.

13. Disciplinary actions for failure to follow established rules. This policy applies to both hourly 

and supervisory personnel.

14. Routine annual or biennial physical examination for all employees by an in-plant Medical 

Department (for small plants the examination is performed by a pre-selected outside 

physician and the results and records sent to the company).

15. Firefighting training is given to all employees based on the level of protection a facility has 

chosen to comply with under OSHA Subpart ”L” Standard first aid training is also highly 

recommended.

Emergency Related Procedures

Emergency related procedures include:

1. Fire brigade and/or emergency response teams trained and equipped to comply with OSHA 

Subpart “L” 1910.130. 

2. Written instructions used by production operators, which outline the hazards associated with 

any job, they are expected to perform and including routine precautions for handling all 

chemical substances involved in their work. Clean up procedures for minor and major spills 

are included.

3. When a spill extends beyond the capabilities of the local personnel, the emergency 

response team will be called. Emergency evaluation procedures exist for each building.

4. Any new process or modification of an existing process must undergo a Hazards and 

Operability Review (HAZ-OP). Before the process is actually started up or modification 

implemented, a Pre Startup Safety Review (PSSR) must also be completed to insure that 

the items raised during the HAZ-OP have been adequately addressed. Any additional 

action items raised during the PSSR must be addressed before start-up.
Engineering Safeguards

Safeguards to Prevent Worker Exposure

1. This section describes the general Industrial Hygiene Program maintained by the Company. 

The proper breathing, eye protection, and protective clothing (chemical resistant suits) have 

been designated for each process after careful study to insure compatibility with the 

chemicals in use. This insures that the protective devices will provide the workers with the 

best possible protection.

2. Eyewash and shower stations are located in close proximity to the reactors and sampling 

points. All of the samples with the exception of sampling the truck are also taken using an 

enclosed sampling device, which is designed to minimize the exposure of the operator to the 

process stream.

3. At the use site for the NCS, the equipment has been designed to be operated as a closed 

process system whenever possible. Solid handling is minimized by the use of automated 

centrifuges and drum emptying equipment that will limit the operator’s exposure to the NCS 

and other chemicals. This along with protective equipment should eliminate worker 

exposure to the NCS.

4. Reactors normal vents are vented to incinerators. Local building specific ventilation consists 

of two separate systems using two exhaust fans located on the roof.

Safeguards to Prevent Fire

During the use of the NCS the reactors will always be inerted to a thermal oxidizer and a set 

nitrogen purge. To prevent static build up, equipment will also be properly bonded and 

grounded. Liquid free falls will also be avoided.