| Protective
Equipment and Disinfection solutions: |
|
Equipment and disinfectant
must be maintained near all areas where biohazardous materials are handled
or stored and must be readily available at all times. A working solution
(if appropriate) should be prepared regularly and dated. Discard expired
solutions on a regular basis. Sufficient volumes (~4L) should be available
to deal with the volumes of potential spills in the area and should be
appropriate for the nature of the organism involved. Stock solutions should
be available in addition to the working concentrations.
|
Personal
Protective Equipment
there should be enough for at least two workers (never work alone doing
a cleanup) and should include: |
|
- lab coat or coveralls
- rubber/plastic
apron
- rubber boots
- heavy rubber gloves
(gauntlets preferred over latex examination gloves)
- particle mask
- HEPA filter mask
if infection via respiratory route is possible
- eye goggles (not
just safety glasses)
|
Chemical
disinfectant stock/working solution
(marked
with date received and expiry date) |
- dilution containers
- dilution instructions
- paper towels (or
similar adsorbent material)
- mop and pail
- squeegee
- tongs (for broken
glass recovery)
- autoclave bags
(6)
|
|
Some
Characteristics of Chemical Disinfectants
Information
adapted from "Concepts in Biosafety; Office of Environmental Health &
Safety, University of Alberta (revised 1998)"
|
| Definitions: |
|
Stock solution refers to the concentrated form as received from the supplier. Sometimes
different concentrations are available so be sure to indicate this. Mark
the date received on the container.
Work solution:
the concentration of solution prepared from the stock by diluting it with
some solvent; specify solvent (water, alcohol, etc) and details of proportions
to be mixed. Mark the date prepared on the container if the Work solution
is stable for a time after preparation.
Active ingredient concentration: some working solutions are described in terms of the
concentration of active agent in the working solution. If the stock solution
is not 100% active ingredient, then you must calculate the concentration
of active ingredient in the stock to get the correct concentration in
the final working solution. |
|
Expressing Concentration:
v = volume, (v/v is ml/100 ml)
w = weight, (w/v is g/100ml)
|
| Example: household
bleach is 5% (w/v) sodium hypochlorite. If you want 0.5% hypochlorite in
the working solution, then dilute 100 ml of bleach with 900 ml water to
get a 10% (v/v) solution of the original stock concentration. If you had
a 12% bleach stock, then would mix 42 ml of bleach stock with 958 ml water
(this is a 4.2% (v/v) solution of the original stock. |
| Note: Double
check manufacturer's dilution recommendations for all solutions as some
of the following concentrations are based on reports from other publications.
They may be wrong or the manufacturer may have altered their formulation. |
| |
| Category: |
Quaternary
ammonium detergent |
| Trade
Name: |
Roccal™,
OstroSan™ |
| Working
Concentration: |
0.4
- 0.8% (v/v) |
| Mixing: |
4
- 8 ml stock / liter water |
| Contact
Time (min): |
30 |
|
Notes - quaternary ammonium compounds:
-
solution
is bacteriocidal, fungicidal and virucidal (on lipophilic viruses
only)
-
NOT
effective against tuberculosis or bacterial spores
-
concentrated
stocks very injurious to eye; wear eye protection when diluting | |
|
| Category: |
alcohol |
| Trade
Name: |
ethanol
or isopropanol |
| Working
Concentration: |
70%
(v/v) |
| Mixing: |
700
ml alcohol + 300 ml of water |
| Contact
Time (min): |
30 |
-
no
residue, not corrosive
-
is
slow acting, may evaporate from surface before disinfection
is complete
-
is
flammable
-
effective
on vegetative bacteria and lipid viruses; less effective on
non-lipid viruses;
-
NOT
effective on bacterial spores | |
|
| Category: |
Bleach
(household) |
| Trade
Name: |
Chlorox™,
Javex™ (5.25% hypochlorite) |
| Working
Concentration: |
0.5%
(w/v) hypochlorite for routine use or 3.0 % (v/v) hypochlorite for
bacterial spores |
| Mixing: |
100
ml stock + 900 ml water or
600 ml stock + 400 ml water (spores) |
| Contact
Time (min): |
30 |
-
household
bleach is about 5% (w/v) sodium hypochlorite; can get a 12%
stock so should adjust your dilution to get the appropriate
working concentration.
-
a
strong oxidizer; avoid mixing with other chemicals
-
produces
free chlorine in solution, is corrosive on metals. Wash area
with soap/water after bleach has been removed
-
working
solutions must be made fresh (daily); diluted stock quickly
loses it’s activity
-
unopened
stock bottle probably good for 6 months. Label date received
and expiry date
-
very
effective disinfectant against many biohazards: bacteria (vegetative and spores), lipid and non-lipid viruses
-
need
high concentrations to kill tuberculosis bacteria and bacterial
spores (use a 60% (v/v) solution of household bleach)
-
chlorine
binds to proteins so if have a lot of protein in your samples
(e.g. blood or cells grown in fetal calf serum), may need to
use a higher concentration than 10% (v/v)
-
should
not autoclave bleach solution as chlorine gas may be released
from the autoclave.
-
also
available in tablet form called Presept™, dissolve in water
and use. Presept is manufactured by Johnson&Johnson and
may be available from a medical, dental or veterinary supply
dealer. | |
|
| Category: |
Iodine |
| Trade
Name: |
Wescodyne™ |
| Working
Concentration: |
0.45%
iodine in solution or 2.5% (w/v) for bacterial spores |
| Mixing: |
4.5
ml / liter water or 25 ml stock + 975 ml of 50% (v/v) ethanol
in water (for spores) |
| Contact
Time (min): |
30 |
|
| |
|
| Category: |
phenolics |
| Trade
Name: |
Dettol
™ , Lysol™ (5-7% phenols) |
| Working
Concentration: |
0.1-0.3%
(w/v) of active ingredient |
| Mixing: |
10
- 50 ml stock / liter water |
| Contact
Time (min): |
30 |
-
compounds
are derivatives of phenol
-
effective
against some lipid viruses, ricekettsia, fungi, vegetative bacteria and tuberculosis
-
NOT effective against bacterial spores and non-lipid viruses
-
unpleasant
odor, leaves sticky residue
-
concentrated
stocks very injurious to eye; wear eye protection when diluting | |
|
| Category: |
chemical
cocktail |
| Trade
Name: |
Super-Phen
Plus™ |
| Working
Concentration: |
0.63%
(v/v) |
| Mixing: |
check
manufacturer's recommendation |
| Contact
Time (min): |
30 |
-
broad
spectrum chemical mixture
-
effective
on most biohazards including tuberculosis and bacterial spores
-
could
be a good choice for a spill cleanup disinfectant because it
is broadly effective | |
|
| Category: |
glutaraldehyde |
| Trade
Name: |
Cidex™ |
| Working
Concentration: |
2%
(w/v) glutaraldehyde in water |
| Mixing: |
check
manufacturer's recommendation |
| Contact
Time (min): |
30 |
-
kills
bacteria (vegetative and spores) and viruses ( lipid and non-lipid)
-
solution
is irritating to nose, eyes and skin
-
can
cause skin sensitization, liver damage and has a low exposure
limit to people
-
less
toxic than formaldehyde
-
a
glutaraldehyde solution is stable for a long time but is not
microcidal until the solution is ‘activated’ by adjusting the
pH to ~7.7 with sodium bicarbonate.
-
after
activated, the solution is useful for 7 – 18 days depending
on the formulation | |
|
| Category: |
formaldehyde |
| Trade
Name: |
formalin
(37% formaldehyde (w/v) in water) |
| Working
Concentration: |
0.2
- 8% formaldehyde in water |
| Mixing: |
5
- 220 ml of 37% stock / liter of water |
| Contact
Time (min): |
30 |
-
effective
biocidal agent but difficult to handle
-
very
toxic, a carcinogen, a respiratory irritant
- formaldehyde is a gas;
usually used as a solution called formalin (37% w/w formaldehyde
+ 12% methanol)
- also available
as a solid (paraformaldehyde) which releases formaldehyde gas
when heated. This is how biohazard cabinets are decontaminated
by a trained technician.
- formalin
is unlikely to be a good choice for cleaning up a spill in an
open lab but it might be used to treat material in a sealed container
| |
| |
orig: June
1999
rev: Mar 2009 |
