Table 1

Investigations of exposure to CO and NO2 in enclosed ice rinks

Study (ref No)Type of studyIdentified risk factorsKey health effects or attack rateBiomonitoring CO, NO2, and key findingsAuthor recommendationsFollow up
EpI, epidemiological investigation; EnI, environmental investigation; MIR, malfunctioning ice resurfacing machine; gIR, gasoline resurfacing machine; pIR, propane resurfacing machine; eIR, electric resurfacing machine; ppm, parts per million; ppb, parts per billion; IV, inadequate ventilation; RMIR, regular maintenance of ice resurfacing machine; ICM, install catalytic muffler; ReIR, replace with electric ice resurfacing machine; AV, adequate ventilation; ARI, NO2-induced acute respiratory illness; Haem, NO2 induced haemoptysis; COP, carbon monoxide poisoning; QT, qualified technican.
1EnI or EpIMIR, IVCOPRange: 25–50 ppm CO↓ Standards for indoor air quality?
2EnI or EpIgIR and pIRCOPAfter incident 100 ppm COAdjust air fuel mixture,?
Warm up gIR and pIR,
Shorten resurfacings,
↓ No of resurfacings
3EnI or medical reportsMIR, IVARIAfter incident 3 ppm NO2Long exhaust pipe,?
Temperature inversion maintained highRMIR, ICM, AV
↑ Exposure time,
↑ Probability of poisoning
4EnI/EpIMIR, IVARI 69%, Haem 20%After incident 3–4 ppm NO2Routine monitoring?
5EnI or clinical investigationMIR, IVCOPAfter incident 100 ppm CORMIR, AV, ReIR,After AV 23 ppm CO
Rink employeesAfter warning signs,After ReIR 1 ppm CO
Routine monitoring,
↓ Standards for indoor air quality
6EnI or EpIMIRCOPAfter incident 100 ppm COAV, RMIRAfter ICM, RMIR 5–10 ppm CO
7EnI or clinical investigationMIR, IVARIAfter incident 4 ppm NO2??
8EnI or EpIMIR, IVCOP, Team A 100%,After incident 47 ppm COAV?
Team B 83%
Medical personnel 100%
Referees 50%
9EnI or EpIMpIR, IVARI 55.6%After incident 1250 ppb NO2AV, ReIR,?
↑ Risk of pulmonary symptoms with ↑ time on iceRoutine monitoring
Set guidelines for air quality
10EnI or EpIMIR, IVNO2 induced severe symptoms 82%,After incident range: 0.5–1 ppm NO2AV, ReIR, RMIR?
Mild symptoms 100%
11EnI or EpIMIR, IVCOP 54% players,After incident 40 ppm CO??
Coaches, teachers
12EnI or clinical investigationMIR, IVARI 48% playersAfter incident 150 ppm COAV, ReIR, RMIR?
SpectatorsAfter incident 1.5 ppm NO2Education of staff
13EnI 20 rinksMIR, IV?73 ppm CORMIR, ReIR, AV?
0.1 ppm NO2
↑ No of resurfacings
↑ CO
Rinks varied in CO
14EnIMIR, IV?4240 ppb NO2Lower NO2?
1 hour maximal
Increased NO2
15EnI 332 rinksMIR, IV?40% rinks ↑ NO2ReIR?
16EnI 70 rinksMIR?Indoor NO2 10× v outdoorLong exhaust pipe?
60% Exceeded standardsAV,
1 hour standard↓No of resurfacings
40% Exceeded standards
1 week average standard
1 week average 180 ppb NO2
17EnI 70 rinksMIR?Outdoor rink = 16.3 ppb NO2Set guidelines for air quality?
Indoor rink = 169.5 ppb NO2AV, ReIR
Indoor NO2 10× v outdoor
NO2 higher in rinks with IV
18EnI or clinical investigationMIR, IV↑ COHbRange: 55–65 ppm CORMIR, QT?
Rink employeesFresh air supply to inside rink
Direct exhaust link from garage to outside
19EnI seven rinksMIR, IV?Range: 3–57 ppm COShorten resurfacings,?
Ventilation system not in operation during resurfacingsAV, ReIR, RMIR
Routine monitoring
20EnI or EpIMIR?50% of rinks exceeded 25 ppm CO,Routine monitoring?
Range: 25–206 ppm CO,QT, AV
Ventilation system not in operation during resurfacings
21EnI six rinksgIR and pIR, IV?gIR range: 157–304 ppm COICM, AV, ReIRAfter ICM
pIR range: 75–175 ppm COgIR range: 4–110 ppm CO
pIR range: 0–105 ppm CO
22EpITobacco smoke?1110–1700 ppm CO2??
237 ppb NO2
23EnI or clinical investigationMIRARIIncreased NO2Corticosteroid treatmentCondition improved
24EnI four rinksMIR, IV?Range: 5–110 ppm COAV, ReIR, ICM, RMIR,?
22.5 ppm caused various CO symptomsWarm up machine,
Shorten resurfacings,
Open doors of rink,
During resurfacings, QT,
Routine monitoring
25EnI six rinksMIR?Range: 4–117 ppm CO1 hour maximal?
Range: 342–2729 ppb NO2Allowable 20 ppm CO and 25 ppb NO2
Outdoor = 37 ppb NO2
26EnIMIR?1 week averageAV, ReIR,Engineering controls: AV ↓ NO2 65%
pIR: 206 ppb NO2ICM, RMIR
gIR: 132 ppb NO2Routine monitoring
eIR: 37 ppb NO2
27Exposure-absoption??Linear exposure-absoption relation↓ CO in rinks?
28Exposure-absoption 10 rinksMIR?Range: 1.6–131.5 ppm COCO standard of 20 ppm for 90 minutes in rinks?
↑ 10 ppm CO = ↑ COHb 1%
29EnIMIR, IV?Increased COAV, long exhaust pipe?
Open doors of rink during resurfacings,
Warm up machine,
Flexible exhaust hose with direct link to outside
30EnIMIR?1 hour average↑ CO gIR?
17–29 ppm CO↑ NO2 pIR
0.14–3.96 ppm NO2
31EnIMIR?23% Exceeded standardsEnforce regulations?
32EnIMIR, IV?Range: 50–100 ppm CORoutine monitoringAfter RMIR, AV 2–3 ppm CO
33EnI or EpI six rinksMIR, IV5×COHb82% Exceeded standardsRMIR, AV, ReIR?
Range: 23–90 ppm CO