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1. How many workers have the potential for exposure to the chemical, and how many are wearing

respirators? What activities are the workers that wear respirators involved in? 

Consortium members reported a range of workers from 8-20. The number can vary depending on the 

types of tasks being performed on any given day (e.g., maintenance, scale calibrations, filter 

removal/replacement, etc.). One consortium member reported that respirators are not worn during nonintrusive activities such as walking through the plant or sitting in the control room.

One consortium member reported using 3M Versaflo M-400 PAPR (APF=1000).

Consortium member reported a variety of tasks for which workers wear respirators, including:

 opening up the closed system for inspection, cleaning, or repair

 unloading raw materials

 entering confined spaces

 any maintenance work

 opening sagger handling system (inspection/cleaning/maintenance), including changing out

saggers (ceramic trays) and the sagger cleaning brush

 sampling

 changing out filter/mill drop drums

 filter cartridge change out

 mixer cleaning

 finished product packaging

2. It appears that workplace exposure monitoring has been conducted at the worksite(s). What

were the results of the monitoring? 

 Please provide the site monitoring reports since they would possibly contain pertinent

details regarding which workers were selected for monitoring, the sampling and analytical

methods, exposure levels, and the laboratory results.

 Important: Indicate if monitoring was conducted with fully functional engineering controls

in place on the days of the monitoring.

Consortium members reported that all engineering controls were in place and operational at the time 

of monitoring. One consortium member provided the table below in response to this question:

This document is the property of the sponsor and may be used only for that purpose intended by the sponsor. Every 

other or additional use, exploitation, reproduction, publication or submission to other parties requires the written 

permission of the sponsor, with the exception of the recipient regulatory agency acting within the limits of its 

administrative authority pursuant to applicable law (e.g., TSCA). The use of these studies/documents for regulatory, 

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Restriction of Chemical Substances (REACH), without the express written permission of the sponsor is unauthorized 

and strictly prohibited.
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Note for table: Sampling was conducted using 0.8 um MCE filters and a constant flow air sampling pump 

at 2 lpm. The analytical method was NIOSH 7303 using ICP-Mass Spectrometry with a reporting limit of 

0.003 micrograms for each element. Total metals were reported as the sum of the results for cobalt (III) 

oxide, lithium oxide, manganese (IV) oxide and nickel oxide to represent airborne concentrations for the 

NCM substance. 

Another consortium member provided the following information (2-page table).
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3. Describe the engineering controls and other controls and work practices that are currently in

place. 

Consortium companies reported the use of many controls, including local exhaust ventilation, air 

scrubbers and bag filters.

One consortium member offered the following details:

The plant was designed and incorporates state-of-the-art engineering controls, including an enclosed 

process design concept. Enclosed process design is used to accommodate current SNUR. In order to 

avoid dust emissions, the plant, including a 3 story conveyor, is designed to run under a slight under

pressure of around – 5 mbar, by managing either flow or pressure control loops. The exhaust air for each 

process is drawn by the central filter stations. Each process operation has primary control device filter 

installed. In some cases, there is a secondary after filter installed. In some process areas, state-of-the-art 

mechanical seals are installed. Purge air (plant compressed air) ensures operability of equipment seals. 

Purge air is added by variable area flow meter to each purge spot. The packaging process involves a 

stand-alone filter station, only operating when packaging is happening. Packaging booth is designed for 

proper capture velocity. During central filter change out, a Bag-In/Bag-Out concept was designed. Total 

Productive Maintenance (Operator Rounds) and a full PM program are in place. We have removed one 

of the original design screw conveyors that used mechanical purge seals, and have replaced that 

conveyor with one that does not incorporate mechanical purge seals. This removal of the screw feeder 

prevents leaks and subsequent exposure. 

4. Do you anticipate making any changes or additions to existing controls in the future?

The consortium member who offered the detailed response to question #3, offered the following in 

response to this question:

Yes. Another screw feeder, with the same issues previously mentioned, will be replaced soon. The 

packaging system is also being modified. During drum filling, the liner, which is being filled, undergoes a 

slight positive pressure that affects the final weight. In order to correct this weight discrepancy, the 

operator has to manually modify the final weight, which increases the exposure hazard. We will control 

the pressure in the fill bag during final packaging to a manner in which a slight negative pressure is 

predominant.