The Buck Systems range of modular dispensing solutions provide for simple
ergonomic operation whilst ensuring control of the dispensing process.
The control system interlocks the process with the recipe management system
to provide batch data security and traceability for validation purposes.
Additional features such as removable hoppers and additional extraction provide
increased safety for operators and simplicity for cleaning. Solutions range
from single level for simple applications to multiple level, integrated dispensary management systems.
Bulk ingredient dispensing includes fully automated excipient dosing or
interfacing with big-bag bulk ingredients for high containment.
API
(Active Pharmaceutical Ingredient) can be dispensed into a contained charge
vessel, which can then be safely transported to the point of use within the
plant.
Dispensaries - understanding your process
As a key part of any pharmaceutical processing plant, the dispensing area
presents many challenges. In particular, it is important to establish a clear
understanding of both existing processes and products, and future requirements
as far as possible. Buck’s approach to some of the key issues for a dispensary
within a production based plant can be summarised as follows :-
A dispensary can take many forms: single or
multi level, low or high containment levels, commonly incorporating two to four
weigh platforms, a weigh hopper, extraction equipment and sieving equipment.
The dispensary may also include recipe management software, waste disposal
system and a method of handling API.
Excipients and bulk ingredients arrive packaged in various
forms, thus requiring differing handling methods. For small volume dispensaries
or line dedicated dispensaries with a small batch size, the preferred method
may be manual. However, with ever more stringent manual handling regulations,
it may be necessary to add automation and mechanical handling to avoid these
problems. For larger volume plants and larger batch sizes, it is essential to
automate the handling. This is achieved by either simply lifting a pallet with
a local stacker truck, or ideally by using a hoist lifter. The advantage of the
hoist lifter is its ability to simply handle sacks, drums and bags without the
additional difficulties of manoeuvring in what is often a confined area.
Dust
exposure is another key consideration. This obviously
depends on the types of products, local Health and Safety regulations and
dispensary room design. There are several ways to approach this issue, for
example as follows.
1. The traditional method is to rely solely on the room air changes and with
use of operator protection such as dust masks and air hoods.
2. An alternative approach is to establish an air curtain across the inlet
of the weigh hopper. This is a simple but very effective solution provided that
the equipment design and extraction levels are properly integrated.
3. Another alternative is use of an extraction hood above the weigh hopper,
enabling the operator to dispense ingredients within the extraction zone. This
provides additional protection, thereby ensuring a high level of safety, in a
cost effective manner.
4. Extraction booths and laminar flow booths are also often used, sometimes
in conjunction with the above solutions, to create an additional airflow away
from the operator. This extra protection offers improved flexibility in the
working area, although special airflow patterns may be required to ensure safe
airflow is achieved around the weigh hopper and any other equipment within the
booth.
5. For toxic materials, an isolator may be required, however the number of
isolators should be limited due to the comparatively high capital and operating
expenses. The use of contained charge vessels can significantly reduce the
requirement for isolators, especially when
incorporated in the process
plant design.
The weigh system typically includes a bench top scale, floor scale and load
cells on the dispensing hopper. In addition there may be a weigh frame for
‘check weigh’ purposes. The weigh frame may be located on the same level, or
ideally, when charging Intermediate
Bulk Containers (IBC system), on the floor level below. When filling the
IBC on the lower level, it is also possible to integrate the weigh frame into a
post hoist to lift and dock at
ceiling height,
although this can reduce system accuracy.
Sieving is common
requirement and must be incorporated in the design of the dispensary to ensure
that suitable air flows and dispensary ergonomics are achieved.
The API can be handled in several ways depending on the containment level
recommended by the plant Occupational Hygienist. For example, transferring the
required quantity of API into a contained charge vessel within an extraction booth or dedicated isolator
as mentioned above. This charge vessel, incorporating a Buck® split valve technology can
be manually moved safely around the plant to enabling the API to be safely used
at the ‘point of use’. Furthermore, ideally the API can be transferred into a
contained charge vessel at the primary production plant, already prepared for
dispensing at the point of use, or for contained dosing, negating the need for
an isolator.
Recipe management can be achieved in several ways; a paper driven system
requiring the operator to record all weigh dispensing operations, a simple
recipe display driven and paper based system, or a full SCADA driven system
guiding the operator through all key stages ensuring complete control and batch
data security in accordance with 21 CFR part 11 – Electronic Signatures and
Records. It is essential that a dispensary control system is practical for the
operator, e.g. use of bar code scanner with intelligent hand held displays to
assist in inventory management, limiting operator intensive tasks and improving
production efficiency.
Buck Systems will normally supply the dispensary system as an integrated
package with the specification and design incorporating key issues such
as: interchangeable weigh hoppers, batch data security and traceability, ease of maintenance,
cleanability, building and utility requirements, and all process
requirements.