Journal
of Hospital
Infection
18, 63-66
(1991)
SHORT
Refrigerated
food storage
G. Goldthorpe, Department
REPORT
of Microbiology,
in hospital
P. Kerry
areas
and Y. J. Drabu
North Middlesex London N18 1QX
Accepted for publication
ward
Hospital,
20 February
Sterling
Way,
1991
Summary: A survey of ward refrigerators was carried out in two hospitals, with reference to type and efficiency in maintaining cold storage temperatures. A total of 40 refrigerators were surveyed on two occasions. Only seven were found to maintain temperatures between 5°C and 7°C. Commercial larder type refrigerators are recommended for ward use. Training and updating of staff in policies and procedures is emphasized. Keywords:
Food
storage,
refrigeration,
hospital
wards.
Introduction
The Department of Health have recently published guidelines’ and legislation2v3 which stress the need to store perishable food at or below 5°C to inhibit the multiplication of pathogenic organisms. As yet there are no guidelines from the Department of Health on the design, maintenance or use of refrigerators, especially those used in health care premises where there should be an added emphasis on safety because of the increased susceptibility of the patient population. We surveyed all the refrigerators in two hospitals in Haringey District to assess: (i) their efficiency in maintaining cold storage temperature; and (ii) usage and maintenance by ward staff. The refrigerators were used to store food items required for patients, e.g. dairy products, or food brought in by relatives. Ward refrigerators were not used to store cook-chill products. Methods
Two complete surveys of all ward refrigerators October 1988 and the second 7 weeks later. Correspondence to: Dr Yasmin J. Drabu, Middlesex Hospital, London N18 1QX.
Consultant
0195-6701/91/050063+04$03.00/0
were carried out, the first in Ambient temperatures were
Microbiologist,
Dept
of Microbiology,
0 1991 The Hospital
63
Infection
North
Society
64
G. Goldthorpe
et al.
noted on both occasions. An inspection of the site, state of repair, capacity, type and approximate age of the refrigerator was followed by a check of food temperature with a digital probe thermometer (Digitron model no. 1204, calibrated to National Physical Laboratory Standards). The item tested in each case was milk which is delivered at the same time each day (delivery temperature 7°C) to every ward and which is stored in approximately the same position in the lower half of each refrigerator. The ward visits took place at least 2 hours after the delivery time to enable the temperature of the milk to stabilize. The refrigerator dial setting was noted and, where found to be unsuitable, was adjusted and a retest performed. Results
The first survey included 40 wards and the second 39 wards (one ward was closed). The ambient temperature was approximately 21°C on the first occasion and 15°C on the second. In one block of wards the design of the ward kitchens was such that the refrigerator was placed next to a large radiator and close to a sunny window, thus giving a higher temperature reading when the ambient temperature was raised. All the refrigerators were of the domestic larder type with variable capacity ranging from 5-7 cubic ft. Thirteen refrigerators had freezer compartments. The thermostats of 36 cabinets were set very close to a ‘maximum’. In the remaining four cabinets, after resetting the dial to a lower temperature and retesting, only one achieved a satisfactory result. These four cabinets were still set correctly at the second inspection. None of the cabinets had an automatic defrost cycle or an integral temperature indicator. No refrigerator or freezer thermometer was in use. Only seven of the 40 refrigerators were found to be in a satisfactory condition of internal and external repair, domestic maintenance, and ability to maintain product temperature between 5°C and 7°C (Figure 1). Only one refrigerator maintained product temperature below 5°C. All these refrigerators were less than 5 years old. A further 22 refrigerators maintained product temperature below 10°C but only 11 of these were in a satisfactory state of maintenance and repair. Eleven cabinets were unacceptable as product temperatures were found to be above 10°C on both occasions, even on a maximum setting (eight of these were on acute medical and surgical wards and three on wards for care of the elderly).
Discussion
Domestic refrigerators are totally inadequate for hospital wards where the amount stored and frequency of use is much greater than in the home. Their design does not allow easy maintenance. Commercial refrigerators with automatic defrost cycles are safer and more hygienic because they are better able to maintain temperatures below 5°C when opened frequently, and are easier to clean. They cost less than domestic refrigerators in the long term
Ward
refrigeration
of food
25 ,
Refrigerator
temperature
(“C)
Figure 1. Survey of 40 ward refrigerators in Haringey District to determine operating temperatures. 0 Less than 5 years old; EA more than 5 years old.
age and
because they are more reliable. Following our investigations the following recommendations were made. A commercial type larder refrigerator with operating temperature of 3-6°C was chosen for installation in all locations from which services were directly provided for patients. It is important to note that if storage of cook-chill products is required, refrigerators which can maintain product temperature below 3°C are required. Initial monitoring of air temperature in situ using a temperature recorder with print facilities (Kane and May model no. 1202, calibrated to National Physical Laboratory Standards) confirmed a constant air temperature over a 72 h period of less than 5°C when the cabinet was set at ‘3’ in mid-scale. Frequent independent checks showed that food temperatures throughout the cabinet were always less than 7°C. These checks were carried out in July 1989 when the ambient air temperature was around 28°C. Whilst design and specification are important when choosing equipment, good maintenance and sound usage are essential for safe and efficient operation. In refrigerators used by staff for patients, a strict stock rotation system with date coding of all foodstuffs on receipt and regular checking, and discarding if necessary, was introduced. Guidance notes (Table I) on range of foods to
66
G. Goldthorpe Table
Refrigerator
I. Policies
et al.
and procedures
for
training
rules
1. Stock rotation is essential First in-first out 2. Observe ‘Best before’/ ‘Use by’ dates 3. Label-Date -Time -Name 4. Check daily Refrigerator stock control For food only (No cook-chill products) Type 1. High risk food 2. Cooked food 3. Packaged/prepared food 4. Dairy goods 5. All food to be covered and in suitable above raw food.
Example Fresh cream, chilled desserts Quiche, cooked meat Wrapped sandwiches Butter, cheese spread, milk containers. Cooked and high risk goods placed
be stored and organization of storage areas were issued to all users. Independent thermometers were fitted inside cabinets and checked regularly. Training for all relevant staff groups in policies and procedures was updated. References 1. Department of Health. Chilled and Frozen. Guidelines on Cook-Chill and Cook-Freeze Catering System. London: HMSO 1988. 2. Department of Health. The Food Safety Act. London: HMSO 1990. 3. Department of Health. The Microbiological Safety of Food. The Richmond Report. London: HMSO 1990.
of Hospital
Infection
18, 63-66
(1991)
SHORT
Refrigerated
food storage
G. Goldthorpe, Department
REPORT
of Microbiology,
in hospital
P. Kerry
areas
and Y. J. Drabu
North Middlesex London N18 1QX
Accepted for publication
ward
Hospital,
20 February
Sterling
Way,
1991
Summary: A survey of ward refrigerators was carried out in two hospitals, with reference to type and efficiency in maintaining cold storage temperatures. A total of 40 refrigerators were surveyed on two occasions. Only seven were found to maintain temperatures between 5°C and 7°C. Commercial larder type refrigerators are recommended for ward use. Training and updating of staff in policies and procedures is emphasized. Keywords:
Food
storage,
refrigeration,
hospital
wards.
Introduction
The Department of Health have recently published guidelines’ and legislation2v3 which stress the need to store perishable food at or below 5°C to inhibit the multiplication of pathogenic organisms. As yet there are no guidelines from the Department of Health on the design, maintenance or use of refrigerators, especially those used in health care premises where there should be an added emphasis on safety because of the increased susceptibility of the patient population. We surveyed all the refrigerators in two hospitals in Haringey District to assess: (i) their efficiency in maintaining cold storage temperature; and (ii) usage and maintenance by ward staff. The refrigerators were used to store food items required for patients, e.g. dairy products, or food brought in by relatives. Ward refrigerators were not used to store cook-chill products. Methods
Two complete surveys of all ward refrigerators October 1988 and the second 7 weeks later. Correspondence to: Dr Yasmin J. Drabu, Middlesex Hospital, London N18 1QX.
Consultant
0195-6701/91/050063+04$03.00/0
were carried out, the first in Ambient temperatures were
Microbiologist,
Dept
of Microbiology,
0 1991 The Hospital
63
Infection
North
Society
64
G. Goldthorpe
et al.
noted on both occasions. An inspection of the site, state of repair, capacity, type and approximate age of the refrigerator was followed by a check of food temperature with a digital probe thermometer (Digitron model no. 1204, calibrated to National Physical Laboratory Standards). The item tested in each case was milk which is delivered at the same time each day (delivery temperature 7°C) to every ward and which is stored in approximately the same position in the lower half of each refrigerator. The ward visits took place at least 2 hours after the delivery time to enable the temperature of the milk to stabilize. The refrigerator dial setting was noted and, where found to be unsuitable, was adjusted and a retest performed. Results
The first survey included 40 wards and the second 39 wards (one ward was closed). The ambient temperature was approximately 21°C on the first occasion and 15°C on the second. In one block of wards the design of the ward kitchens was such that the refrigerator was placed next to a large radiator and close to a sunny window, thus giving a higher temperature reading when the ambient temperature was raised. All the refrigerators were of the domestic larder type with variable capacity ranging from 5-7 cubic ft. Thirteen refrigerators had freezer compartments. The thermostats of 36 cabinets were set very close to a ‘maximum’. In the remaining four cabinets, after resetting the dial to a lower temperature and retesting, only one achieved a satisfactory result. These four cabinets were still set correctly at the second inspection. None of the cabinets had an automatic defrost cycle or an integral temperature indicator. No refrigerator or freezer thermometer was in use. Only seven of the 40 refrigerators were found to be in a satisfactory condition of internal and external repair, domestic maintenance, and ability to maintain product temperature between 5°C and 7°C (Figure 1). Only one refrigerator maintained product temperature below 5°C. All these refrigerators were less than 5 years old. A further 22 refrigerators maintained product temperature below 10°C but only 11 of these were in a satisfactory state of maintenance and repair. Eleven cabinets were unacceptable as product temperatures were found to be above 10°C on both occasions, even on a maximum setting (eight of these were on acute medical and surgical wards and three on wards for care of the elderly).
Discussion
Domestic refrigerators are totally inadequate for hospital wards where the amount stored and frequency of use is much greater than in the home. Their design does not allow easy maintenance. Commercial refrigerators with automatic defrost cycles are safer and more hygienic because they are better able to maintain temperatures below 5°C when opened frequently, and are easier to clean. They cost less than domestic refrigerators in the long term
Ward
refrigeration
of food
25 ,
Refrigerator
temperature
(“C)
Figure 1. Survey of 40 ward refrigerators in Haringey District to determine operating temperatures. 0 Less than 5 years old; EA more than 5 years old.
age and
because they are more reliable. Following our investigations the following recommendations were made. A commercial type larder refrigerator with operating temperature of 3-6°C was chosen for installation in all locations from which services were directly provided for patients. It is important to note that if storage of cook-chill products is required, refrigerators which can maintain product temperature below 3°C are required. Initial monitoring of air temperature in situ using a temperature recorder with print facilities (Kane and May model no. 1202, calibrated to National Physical Laboratory Standards) confirmed a constant air temperature over a 72 h period of less than 5°C when the cabinet was set at ‘3’ in mid-scale. Frequent independent checks showed that food temperatures throughout the cabinet were always less than 7°C. These checks were carried out in July 1989 when the ambient air temperature was around 28°C. Whilst design and specification are important when choosing equipment, good maintenance and sound usage are essential for safe and efficient operation. In refrigerators used by staff for patients, a strict stock rotation system with date coding of all foodstuffs on receipt and regular checking, and discarding if necessary, was introduced. Guidance notes (Table I) on range of foods to
66
G. Goldthorpe Table
Refrigerator
I. Policies
et al.
and procedures
for
training
rules
1. Stock rotation is essential First in-first out 2. Observe ‘Best before’/ ‘Use by’ dates 3. Label-Date -Time -Name 4. Check daily Refrigerator stock control For food only (No cook-chill products) Type 1. High risk food 2. Cooked food 3. Packaged/prepared food 4. Dairy goods 5. All food to be covered and in suitable above raw food.
Example Fresh cream, chilled desserts Quiche, cooked meat Wrapped sandwiches Butter, cheese spread, milk containers. Cooked and high risk goods placed
be stored and organization of storage areas were issued to all users. Independent thermometers were fitted inside cabinets and checked regularly. Training for all relevant staff groups in policies and procedures was updated. References 1. Department of Health. Chilled and Frozen. Guidelines on Cook-Chill and Cook-Freeze Catering System. London: HMSO 1988. 2. Department of Health. The Food Safety Act. London: HMSO 1990. 3. Department of Health. The Microbiological Safety of Food. The Richmond Report. London: HMSO 1990.
