GENERAL RISK ASSESSMENT
SECTION 1 HAZARD IDENTIFICATION
Department
IMS-MRL (Clinical Biochemistry)
Date of Assessment
24/02/03; Updated 26/10/04; Updated
04/03/2011
Area/Plant/Equipment
Name and Signature of Assessor (or team)
Liquid nitrogen use
Malgorzata Martin (CNH)/ Chris Ford
Jonathan Fort (on 4th March 2011)
Task/Activity/Operation
- Snap freezing samples in liquid nitrogen
- Cell storage in liquid nitrogen
- Defrosting samples stored in liquid
nitrogen
- Transport of liquid nitrogen to CBS
Task Reference No.
6
HAZARD
WHO COULD BE
HARMED(e.g.
**public, operator)
Numbers of people
likely to be harmed
Nature of Harm
Hazard
Reference
No.
Very low
temperature
related
Operator, Any
person in proximity
1
6a
Evaporation of
nitrogen from the
tanks
(asphyxiation)
The explosion
potential of the
tank/cylinder as a
pressure vessel
Explosion of
cryovails taken
from cryovessels
Operator, Any
person in proximity
Especially when
transported in lift
Operator, Any
person in proximity
1
Cold burns,
frostbites, severe
blistering,
hypothermia
Depletion of oxygen
content,
asphyxiation
1
Trauma injuries,
frostbites, burns,
severe blistering
6c
Operator, Any
person in proximity
1
6d
Manual handling of
heavy
tanks/containers
Employees
receiving,
despatching or
moving large
tanks/containers
1
Trauma injuries,
frostbites, burns,
severe blistering,
contact with foreign
materials stored in
cryovails (possible
infection)
Musculo-skeletal or
trauma injuries
** see section 3 –Special Considerations
6b
6e
SECTION 2 – RISK EVALUATION
Note: Section 2 &3 must be completed for each hazard identified in Section 1
Hazard from section 1
Reference No.
Very low temperature related
6a
Make an assessment without taking into account current control measures (subjective)
RISK = Probability of Harm
PROBABILITY
1
2
3
X
SEVERITY OF HARM
1
2
3
=
RISK LEVEL
10
20
30
X
Most Likely Severity (will increase if large numbers will be hurt)
4
5
6
7
8
9
10
4
5
6
7
8
9
10
40
50
60
70
80
90
100
CURRENT CONTROL MEASURES
Type
Control at Engineering
source
controls
(intrinsic)
(guards, local
exhaust ventIllation etc.
Description
Use of
Ventilation of
purpose
area
produced
tanks/cylin For delivery
ders/conta (use of lift) A
iners
warning sign
has been
applied
Are they
Adequate
Measures
Required
By who &
When
Procedural
controls
(inc. training
and
supervision)
Training and
supervision of
new users.
Training to
include: care,
selection and
use of
protective
equipment,
hazards
associated with
use and
emergency
procedures
Personal
protective
equipment
Other
Lab coat;
-Pour liquid nitrogen
warm, dry
carefully and slowly;gloves;
-Only use containers
protective
designed for liquid
face screen
nitrogen use and
or goggles;
transport (should
adequate
have lid and handles)
footwear
-Use forceps to
(avoidance
withdraw objects
of open toed immersed in the
shoes)
liquid nitrogen
- Avoid contact of
liquid nitrogen with
skin, in particular wet
skin
Yes
Yes
Yes
Yes
Yes
-
-
-
-
-
-
-
-
-
-
SECTION 2 – RISK EVALUATION
Note: Section 2 &3 must be completed for each hazard identified in Section 1
Hazard from section 1
Reference No.
Evaporation of nitrogen from the tanks
6b
(asphyxiation)
Make an assessment without taking into account current control measures (subjective)
RISK = Probability of Harm
PROBABILITY
1
2
3
X
SEVERITY OF HARM
1
2
3
=
RISK LEVEL
10
20
30
X
Most Likely Severity (will increase if large numbers will be hurt)
4
5
6
7
8
9
10
4
5
6
7
8
9
10
40
50
60
70
80
90
100
CURRENT CONTROL MEASURES
Type
Control at
Engineering
source
controls
(intrinsic)
(guards, local
exhaust ventIllation etc.
Description
Use of
-Storage in
purpose
well ventilated
produced
but weather
tanks/cylinders protected area
- Yearly
control of
tanks
Procedural
controls
(inc. training
and
supervision)
Training and
supervision of
new users.
Personal
protective
equipment
Other
Are they
Adequate
Additional
Measures
Required
Yes
Yes
Yes
Lab coat;
warm, dry
gloves;
protective face
screen or
goggles;
adequate
footwear
(avoidance of
open toed
shoes)
Yes
-
-
-
-
-
-
By who &
When
-
-
-
-
-
SECTION 2 – RISK EVALUATION
Note: Section 2 &3 must be completed for each hazard identified in Section 1
Hazard from section 1
Reference No.
The explosion potential of the tank/cylinder as a 6c
pressure vessel
Make an assessment without taking into account current control measures (subjective)
RISK = Probability of Harm X Most Likely Severity (will increase if large numbers will be hurt)
PROBABILITY
1
2
3
X
SEVERITY OF HARM
1
2
3
=
RISK LEVEL
10
20
30
4
5
6
7
8
9
10
4
5
6
7
8
9
10
40
50
60
70
80
90
100
CURRENT CONTROL MEASURES
Type
Control at
Engineering
source
controls
(intrinsic)
(guards, local
exhaust ventIllation etc.
Description
- tanks/
- Separation
cylinders fitted
from
with valve
cylinders
protection
containing
guards and
toxics,
appropriate
flammables
pressure
oxidants and
reducing
corrosives by
regulator
distance or
structural
fire-resisting
partitions
- Yearly control
of tanks
Are they
Yes
Yes
Adequate
Additional
Measures
Required
By who &
When
-
-
Procedural
controls
(inc. training and
supervision)
Personal
protective
equipment
Other
Training and
supervision of
new users.
Pressure systems
tested annually by
qualified BOC
engineer as part
of the
maintenance
contract for the
equipment.
Lab coat;
warm, dry
gloves;
protective
face screen
or goggles;
adequate
footwear
-
Yes
Yes
-
-
-
-
-
-
-
SECTION 2 – RISK EVALUATION
Note: Section 2 &3 must be completed for each hazard identified in Section 1
Hazard from section 1
Explosion of cryovials taken from cryovessels
Reference No.
6d
Make an assessment without taking into account current control measures (subjective)
RISK = Probability of Harm X
PROBABILITY
1
2
X
3
Most Likely Severity (will increase if large numbers will be hurt)
4
5
6
7
8
9
10
SEVERITY OF HARM
1
2
3
4
5
6
7
8
9
10
=
RISK LEVEL
10
20
40
50
60
70
80
90
100
30
CURRENT CONTROL MEASURES
Type
Control at
Engineering
source
controls
(intrinsic)
(guards, local
exhaust ventIllation etc.
Description
- use of
appropriate
cryovials
Procedural
controls
(inc. training
and
supervision)
Training and
supervision of
new users.
Personal
protective
equipment
Other
Lab coat;
warm, dry
gloves;
protective face
screen or
goggles;
adequate
footwear
Are they
Adequate
Additional
Measures
Required
Yes
-
Yes
Yes
Physical
containment of
cryovails
during
transport e.g.
use of
polystarine
box for
transport
Yes
-
-
-
-
-
By who &
When
-
-
-
-
-
SECTION 2 – RISK
EVALUATION
Note: Section 2 &3 must be completed for each hazard identified in Section 1
Hazard from section 1
Reference No.
Manual handling of heavy tanks/containers
6e
Make an assessment without taking into account current control measures (subjective)
RISK = Probability of Harm X Most Likely Severity (will increase if large numbers will be hurt)
PROBABILITY
1
2
3
X
SEVERITY OF HARM
1
2
3
=
RISK LEVEL
10
20
30
4
5
6
7
8
9
10
4
5
6
7
8
9
10
40
50
60
70
80
90
100
CURRENT CONTROL MEASURES
Type
Control at
Engineering
source
controls
(intrinsic)
(guards, local
exhaust ventIllation etc.
Description
Cylinders/tanks Yearly control
equipped with
of tanks
wheels by
(inspection)
manufacturers
Procedural
controls
(inc. training and
supervision)
Personal
Other
protective
equipment
Training before
use.
-
Are they
Adequate
Additional
Measures
Required
Yes
Yes
Yes
Yes
-Use of
adequate
mechanical
aids e.g.
wheeled
trolley when
required
-Use of the
smallest
container
consistent
with the
activity or
process
-
-
-
-
-
-
By who &
When
-
-
-
-
-
Use of good
manual handling
practices.
Self assessment
of physical
capability
SECTION3
SPECIAL CONSIDERATIONS
1. After carrying out the assessment and assuming adequate training, is this task one that can
be carried out by a lone worker?
This decision is one made by a group leader, please state their name and answer.
Group leader name: Sue Ozanne
Answer: Yes
2. Are there any special considerations for other groups of workers e.g. Pregnant and new
mothers, young people, cleaners etc. that you have not considered in your main
Assessment? If so, please make a comment below.
SECTION 4- REVIEW
Circumstances for Review
Incident on Friday 4th March 2011 when the liquid nitrogen vessel fell on to it’s side
during transporting from the basement to Level 5 IMS-MRL.
Default Date review: 04/03/2011