16 C.F.R. § 1505.7
Maximum acceptable surface temperatures
The maximum acceptable surface temperatures for electrically operated toys shall be as follows:
| Surface type (as described—in § 1505.6 (g)(2)) | Thermal inertia type 1 | Temperatures | |
|---|---|---|---|
| °C. | °F. | ||
| A | 1 | 50 | 122 |
| A | 2 | 55 | 131 |
| A | 3 | 60 | 140 |
| B | 1 | 55 | 131 |
| B | 2 | 65 | 149 |
| B | 3 | 75 | 167 |
| C (unmarked) | 1 | 65 | 149 |
| C (unmarked) | 2 | 75 | 167 |
| C (unmarked) | 3 | 85 | 185 |
| C (unmarked) | 4 | 95 | 203 |
| C marked | 1 | 70 | 158 |
| C marked | 2 | 90 | 194 |
| C marked | 3 | 110 | 230 |
| C marked | 4 | 130 | 266 |
| D (unmarked) | 1 | 55 | 131 |
| D (unmarked) | 2 | 70 | 158 |
| D (unmarked) | 3 | 80 | 176 |
| D (unmarked) | 4 | 90 | 194 |
| D marked | 1 | 60 | 140 |
| D marked | 2 | 75 | 167 |
| D marked | 3 | 100 | 212 |
| D marked | 4 | 125 | 257 |
| E | (2) | (3) | (3) |
| 1 Thermal inertia types are defined in terms of lambda as follows: | |||
| Type 1: Greater than 0.0045 (e.g., most metals). | |||
| Type 2: More than 0.0005 but not more than 0.0045 (e.g., glass). | |||
| Type 3: More than 0.0001 but not more than 0.0005 (e.g., most plastics). | |||
| Type 4: 0.0001 or less (e.g., future polymeric materials). | |||
| The thermal inertia of a material can be obtained by multiplying the thermal conductivity (cal./cm./sec./degrees C.) by the density (gm./cm.3) by the specific heat (cal./gm./degrees C.). | |||
| 2 All types. | |||
| 3 No limit. | |||