Silica Gel Sachets
Silica gel sachets or bags, are simply flexible 'containers ' of silica gel.
The sachet material has to be robust and capable of withstanding normal handling whilst, most importantly,
being able to breathe. This means that water molecules can pass through the material and be adsorbed by the silica gel.
Standard sachet materials include Tyvek™, laminate, cotton and paper.
Most sachets have heat-sealed seams, the larger bags are sewn.
We produce a range of silica gel sachets using non-indicating (white) or self-indicating (orange to green) silica gels.
In the latter case, the colour of the silica gel is visible through the sachet paper or laminate.
Self-indicating silica gel sachets are often useful in test situations, to confirm the suitability of the sachet size chosen,
or in cases where an item is frequently inspected and the sachet can be replaced if it has become exhausted.
Non-indicating (white) silica gel sachets
½ gram (32 x 20 mm)
1 gram (39 x 20 mm)
3 gram (55 x 25 mm)
5 gram (65 x 30 mm)
10 gram (75 x 40 mm)
These sachets are made as standard in a heat-sealed Tyvek™ material.
Tyvek™ is a very strong dust and lint free material which is ideal for sensitive applications.
Self-indicating (orange to green) silica gel sachets
½ gram (40 x 30 mm)
1 gram (50 x 30 mm)
5 gram (65 x 45 mm)
10 gram (80 x 55 mm)
These sachets are made in a heat-sealed plain paper.
All sachets are printed Silica Gel Do Not Eat
Small silica gel sachets can prevent moisture damage to electrical goods and
electronic components (internally and externally), scientific and optical instruments, communication equipment,
metallic parts, leather goods, tools and many other small to medium sized items in use, store or transit.
For situations where the physical space for a sachet is very restricted, consider silica gel in capsules:
0.3 gram, 0.6 gram and 1 gram.
Non-indicating (white) and self-indicating (orange to green) silica gel sachets
25 gram (115 x 50 mm)
50 gram (130 x 80 mm)
100 gram (170 x 80 mm)
250 gram (185 x 125 mm)
500 gram (270 x 125 mm)
1 kg (320 x 160 mm)
Medium sized non-indicating sachets are made as standard in Tyvek™ and laminate
Self-indicating sachets are manufactured in laminate.
All sachets are printed Silica Gel Do Not Eat and with their weight.
Medium sized silica gel sachets can prevent moisture damage to larger electrical/electronic items,
metallic components and fabrications, contents of export packing cartons or crates and hygroscopic powders.
Non-indicating (white) silica gel cotton bags
2½ kg (38 x 25 cm)
5 kg (55 x 35 cm)
10 kg (70 x 45 cm)
These largest silica gel bags are sewn in cotton to give extra strength and robustness.
The 2½ kg bag has two 30 cm tapes sewn into its seams, so can be hung from a suitable fixing point.
Cotton bags are stamped Silica Gel Do Not Eat and with their weight.
Large silica gel bags can prevent moisture damage to items in transit in packing crates and
shipping containers or protect large machinery and engines and enclosed vessels such as tanks or pipes.
FDA grade silica gel sachets, non-indicating
½ gram (35 x 16 mm)
1 gram (42 x 19 mm)
5 gram (65 x 34 mm)
10 gram (90 x 34 mm)
These sachets are suitable for medical and pharmaceutical applications and are FDA approved for use
in food packaging applications. All sachets are printed Moisture & Odour Adsorbent Do Not Eat (in six languages).
Silica gel sachets, non-indicating to Def Stan 81-68
5 gram (50 x 108 mm)
10 gram (50 x 120 mm)
25 gram (80 x 144 mm)
50 gram (80 x 160 mm)
100 gram (80 x 180 mm)
250 gram (125 x 250 mm)
500 gram (150 x 300 mm)
2½ kg (250 x 380 mm)
This range of sachets are made to Def-Stan 81-68/4. They are made to order.
They are filled with silica gel that conforms to BS:2540 or BS:7554 (granular or beaded silica gel)
and are printed with our (or our customer's) details and also the date of manufacture.
Silica gel sachets to MIL-D-3464E Types I and II
½ unit (95 x 50 mm)
1 unit (115 x 50 mm)
2 unit (130 x 80 mm)
4 unit (170 x 80 mm)
8 unit (175 x 125 mm)
250 gram (185 x 125 mm)
16 unit (255 x 125 mm)
500 gram (270 x 125 mm)
1 kg (320 x 160 mm)
These sachets are made to the military specification MIL-D-3464E.
A 'unit' refers to the weight of desiccant required to meet adsorption capacities laid down by the Standard.
Typically, 25 grams of silica gel = 1 unit.
So, for example, a 16 unit sachet is filled with 400 grams of silica gel (and a 500 gram sachet = 20 units)
The sachets have a two year shelf-life.
Bandoliers are ‘connected’ groups of silica gel sachets. In their simplest form, they are machine made
sachets that have not been individually cut as they are produced, but just left as a ‘string’ of sachets.
This form is mostly only suitable for smaller sachets.
Our standard bandoliers are seven connected ‘pockets’ made using a cotton fabric and where each pocket
contains a 500 gram silica gel sachet. The 500 gram sachets can be filled with either
non-indicating or self-indicating silica gels to commercial or defence standards.
The bandoliers are made such that the sachets cannot fall out of their pockets during normal use and,
as such, are extremely useful when used to protect high value machine parts.
And more. Variations, non-standard sizes and special packing
In addition to our more standard range of sachets, we can also:
Make sachets (10 gram to 1 kg) filled with blue to pink (BS3523:1991) self-indicating silica gel.
Make sachets filled with orange to colourless self-indicating silica gel.
Sew cotton bags, 100 gram to 1 kg, where extra robustness is essential.
Make sachets to any other weight or shape that meets customer's requirements.
Attach loops or lengths of tape to sachets so they can be hung or tied in use.
Individually over-wrap sachets in foil or poly pouches for extended shelf-life or distributed use 'in the field'.
Sew all sizes of sachets in non-woven fabric (or cotton) sachets where regeneration and reuse of sachets is desired.
Make sachets using a mixture of materials e.g. silica gel and molecular sieve or silica gel and activated carbon.
Which Size Sachet To Use?
A silica gel sachet is only effective in an enclosed environment. A physical barrier will prevent water vapour from
continually entering such an environment, leaving the finite volume enclosed to be protected by the silica gel.
A general rule of thumb in a 'hermetically sealed' environment, is that 5 grams of silica gel
are required per cubic foot of enclosed volume (or 170 grams per cubic meter).
It is often prudent to err on the side of caution and use the nearest standard size sachet over the amount
of silica gel that is theoretically required. For large volumes, using a few well spaced
smaller sachets will reduce humidity levels faster than if using a single large sachet.
Often, environments cannot be considered 'hermetically sealed', there will be a number of factors which
will increase the amount of silica gel that is needed. Please read our 'Using Silica Gel' section.
Please contact us for prices.