= 26i=

‘It is also recommended that a continuous dust monitor be purchased
(rental?) for the determination of total dust and total respirable dust. It
should be noted that if such an instrument proves to be Saale it could be
used as a control and monitoring device for recirculated air. Presently we do
have a personal sampler that could be used to determine respirable dust in

conjunction with the fibre concentration using the membrane filter method.

(g) MISCELLANEOUS

In gathering information for this report, I became aware of the lack of
input on our part on future standards. I suggest that a report be compiled of
our recommendations toward a future standard, how we propose to meet this
standard, and monitor it, etc.

Gravimetric sampling should be investigated as a monitoring control
method in lieu of the membrane filter method. |

I recommend that the Senior Inspector be approached on a time weighted
average method of monitoring.

It is my personal belief that weighted averages from location samplings
are not a valid method for determining occupational exposure Bs indicated by
the Environmental Inspector. All monitoring and standards are directed towards
the personal protection of the worker in his immediate working environment.
Therefore in order that a true assessment be given a worker's exposure must be
determined over his 8 hour working period according to our present standard.

Medical scientists need a method of providing an improved data base for
scientifically based standards. Weighted averages and location sampling are
valuable in determining compliance with ceiling limitations (we have none at
present) and for industry to assess environmental control costs.

In the United States, from where we adopted our standard, the method
of monitoring is 8 hour time weighted averages eeooredne to occupational

exposure